From d81de518755a415357c2326d2b9df01ee5acaf62 Mon Sep 17 00:00:00 2001
From: Daniel Reigada <daniel.reigada@gmail.com>
Date: Thu, 15 Aug 2019 13:48:25 +0100
Subject: [PATCH] Update grpc-go from 1.14.0 to 1.23.0 (#279)

---
 Gopkg.lock                                    |  190 ++-
 Gopkg.toml                                    |    2 +-
 pkg/server/gateway.go                         |    1 -
 vendor/google.golang.org/grpc/.travis.yml     |   37 +-
 vendor/google.golang.org/grpc/CONTRIBUTING.md |   58 +-
 vendor/google.golang.org/grpc/Makefile        |   65 +-
 vendor/google.golang.org/grpc/README.md       |  100 +-
 vendor/google.golang.org/grpc/backoff.go      |    2 +-
 vendor/google.golang.org/grpc/balancer.go     |   35 +-
 .../grpc/balancer/balancer.go                 |  110 +-
 .../grpc/balancer/base/balancer.go            |   82 +-
 .../grpc/balancer/base/base.go                |   12 +
 .../grpc/balancer/roundrobin/roundrobin.go    |   16 +-
 .../grpc/balancer_conn_wrappers.go            |   60 +-
 .../grpc/balancer_v1_wrapper.go               |   82 +-
 .../grpc_binarylog_v1/binarylog.pb.go         |  900 +++++++++++++
 vendor/google.golang.org/grpc/call.go         |    4 +-
 vendor/google.golang.org/grpc/clientconn.go   | 1129 ++++++++++-------
 vendor/google.golang.org/grpc/codes/codes.go  |    3 +-
 .../grpc/connectivity/connectivity.go         |    5 +-
 .../grpc/credentials/credentials.go           |   79 +-
 .../grpc/credentials/go16.go                  |   57 -
 .../grpc/credentials/go17.go                  |   59 -
 .../grpc/credentials/go18.go                  |   46 -
 .../grpc/credentials/internal/syscallconn.go  |   61 +
 .../internal/syscallconn_appengine.go}        |   18 +-
 .../grpc/credentials/{go19.go => tls13.go}    |   21 +-
 vendor/google.golang.org/grpc/dialoptions.go  |  170 ++-
 .../grpc/encoding/encoding.go                 |    6 +-
 vendor/google.golang.org/grpc/go.mod          |   19 +
 vendor/google.golang.org/grpc/go.sum          |   37 +
 vendor/google.golang.org/grpc/go16.go         |   71 --
 vendor/google.golang.org/grpc/go17.go         |   72 --
 .../google.golang.org/grpc/grpclog/grpclog.go |    2 +-
 vendor/google.golang.org/grpc/install_gae.sh  |    2 +-
 vendor/google.golang.org/grpc/interceptor.go  |    2 +-
 .../grpc/internal/balancerload/load.go        |   46 +
 .../grpc/internal/binarylog/binarylog.go      |  167 +++
 .../internal/binarylog/binarylog_testutil.go  |   42 +
 .../grpc/internal/binarylog/env_config.go     |  210 +++
 .../grpc/internal/binarylog/method_logger.go  |  423 ++++++
 .../grpc/internal/binarylog/regenerate.sh     |   33 +
 .../grpc/internal/binarylog/sink.go           |  162 +++
 .../go16.go => internal/binarylog/util.go}    |   35 +-
 .../grpc/internal/channelz/funcs.go           |  232 +++-
 .../grpc/internal/channelz/types.go           |  311 ++++-
 .../grpc/internal/channelz/types_linux.go     |    3 +-
 .../grpc/internal/channelz/types_nonlinux.go  |   18 +-
 .../{util_linux_go19.go => util_linux.go}     |    2 +-
 ..._nonlinux_pre_go19.go => util_nonlinux.go} |    2 +-
 .../grpc/internal/grpcsync/event.go           |   61 +
 .../grpc/internal/internal.go                 |   55 +-
 .../grpc/internal/syscall/syscall_linux.go    |  114 ++
 .../grpc/internal/syscall/syscall_nonlinux.go |   73 ++
 .../grpc/internal/transport/bdp_estimator.go  |    7 +-
 .../grpc/internal/transport/controlbuf.go     |   86 +-
 .../grpc/internal/transport/flowcontrol.go    |    3 +-
 .../grpc/internal/transport/go16.go           |   52 -
 .../grpc/internal/transport/go17.go           |   53 -
 .../grpc/internal/transport/handler_server.go |   45 +-
 .../grpc/internal/transport/http2_client.go   |  271 ++--
 .../grpc/internal/transport/http2_server.go   |  255 ++--
 .../grpc/internal/transport/http_util.go      |  179 ++-
 .../grpc/internal/transport/log.go            |    6 -
 .../grpc/internal/transport/transport.go      |  207 ++-
 .../grpc/keepalive/keepalive.go               |   64 +-
 .../grpc/metadata/metadata.go                 |    3 +-
 .../grpc/naming/dns_resolver.go               |   11 +-
 vendor/google.golang.org/grpc/naming/go17.go  |   34 -
 .../google.golang.org/grpc/naming/naming.go   |    3 +-
 vendor/google.golang.org/grpc/peer/peer.go    |    2 +-
 .../google.golang.org/grpc/picker_wrapper.go  |   33 +-
 vendor/google.golang.org/grpc/pickfirst.go    |   20 +-
 vendor/google.golang.org/grpc/preloader.go    |   64 +
 vendor/google.golang.org/grpc/proxy.go        |   52 +-
 .../grpc/resolver/dns/dns_resolver.go         |  102 +-
 .../grpc/resolver/dns/go17.go                 |   35 -
 .../grpc/resolver/dns/go18.go                 |   29 -
 .../grpc/resolver/passthrough/passthrough.go  |    2 +-
 .../grpc/resolver/resolver.go                 |   35 +
 .../grpc/resolver_conn_wrapper.go             |  114 +-
 vendor/google.golang.org/grpc/rpc_util.go     |  188 ++-
 vendor/google.golang.org/grpc/server.go       |  573 +++++----
 .../google.golang.org/grpc/service_config.go  |  105 +-
 .../grpc/serviceconfig/serviceconfig.go       |   48 +
 .../google.golang.org/grpc/stats/handlers.go  |    3 +-
 vendor/google.golang.org/grpc/stats/stats.go  |    6 +-
 vendor/google.golang.org/grpc/status/go17.go  |   44 -
 .../google.golang.org/grpc/status/status.go   |   45 +-
 vendor/google.golang.org/grpc/stream.go       |  636 +++++++++-
 vendor/google.golang.org/grpc/tap/tap.go      |    2 +-
 vendor/google.golang.org/grpc/trace.go        |   13 +
 vendor/google.golang.org/grpc/version.go      |    2 +-
 vendor/google.golang.org/grpc/vet.sh          |  139 +-
 94 files changed, 6751 insertions(+), 2424 deletions(-)
 create mode 100644 vendor/google.golang.org/grpc/binarylog/grpc_binarylog_v1/binarylog.pb.go
 delete mode 100644 vendor/google.golang.org/grpc/credentials/go16.go
 delete mode 100644 vendor/google.golang.org/grpc/credentials/go17.go
 delete mode 100644 vendor/google.golang.org/grpc/credentials/go18.go
 create mode 100644 vendor/google.golang.org/grpc/credentials/internal/syscallconn.go
 rename vendor/google.golang.org/grpc/{naming/go18.go => credentials/internal/syscallconn_appengine.go} (73%)
 rename vendor/google.golang.org/grpc/credentials/{go19.go => tls13.go} (60%)
 create mode 100644 vendor/google.golang.org/grpc/go.mod
 create mode 100644 vendor/google.golang.org/grpc/go.sum
 delete mode 100644 vendor/google.golang.org/grpc/go16.go
 delete mode 100644 vendor/google.golang.org/grpc/go17.go
 create mode 100644 vendor/google.golang.org/grpc/internal/balancerload/load.go
 create mode 100644 vendor/google.golang.org/grpc/internal/binarylog/binarylog.go
 create mode 100644 vendor/google.golang.org/grpc/internal/binarylog/binarylog_testutil.go
 create mode 100644 vendor/google.golang.org/grpc/internal/binarylog/env_config.go
 create mode 100644 vendor/google.golang.org/grpc/internal/binarylog/method_logger.go
 create mode 100755 vendor/google.golang.org/grpc/internal/binarylog/regenerate.sh
 create mode 100644 vendor/google.golang.org/grpc/internal/binarylog/sink.go
 rename vendor/google.golang.org/grpc/{status/go16.go => internal/binarylog/util.go} (51%)
 rename vendor/google.golang.org/grpc/internal/channelz/{util_linux_go19.go => util_linux.go} (96%)
 rename vendor/google.golang.org/grpc/internal/channelz/{util_nonlinux_pre_go19.go => util_nonlinux.go} (95%)
 create mode 100644 vendor/google.golang.org/grpc/internal/grpcsync/event.go
 create mode 100644 vendor/google.golang.org/grpc/internal/syscall/syscall_linux.go
 create mode 100644 vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go
 delete mode 100644 vendor/google.golang.org/grpc/internal/transport/go16.go
 delete mode 100644 vendor/google.golang.org/grpc/internal/transport/go17.go
 delete mode 100644 vendor/google.golang.org/grpc/naming/go17.go
 create mode 100644 vendor/google.golang.org/grpc/preloader.go
 delete mode 100644 vendor/google.golang.org/grpc/resolver/dns/go17.go
 delete mode 100644 vendor/google.golang.org/grpc/resolver/dns/go18.go
 create mode 100644 vendor/google.golang.org/grpc/serviceconfig/serviceconfig.go
 delete mode 100644 vendor/google.golang.org/grpc/status/go17.go

diff --git a/Gopkg.lock b/Gopkg.lock
index 090b74e1..bdb5094e 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -3,20 +3,25 @@
 
 [[projects]]
   branch = "master"
+  digest = "1:315c5f2f60c76d89b871c73f9bd5fe689cad96597afd50fb9992228ef80bdd34"
   name = "github.com/alecthomas/template"
   packages = [
     ".",
-    "parse"
+    "parse",
   ]
+  pruneopts = "UT"
   revision = "a0175ee3bccc567396460bf5acd36800cb10c49c"
 
 [[projects]]
   branch = "master"
+  digest = "1:c198fdc381e898e8fb62b8eb62758195091c313ad18e52a3067366e1dda2fb3c"
   name = "github.com/alecthomas/units"
   packages = ["."]
+  pruneopts = "UT"
   revision = "2efee857e7cfd4f3d0138cc3cbb1b4966962b93a"
 
 [[projects]]
+  digest = "1:663aa72b14f781c4f3f770642fe0c6331e450f45a4c579ffd8fc35387ebb78a6"
   name = "github.com/aws/aws-sdk-go"
   packages = [
     "aws",
@@ -44,255 +49,327 @@
     "private/protocol/query/queryutil",
     "private/protocol/rest",
     "private/protocol/xml/xmlutil",
-    "service/sts"
+    "service/sts",
   ]
+  pruneopts = "UT"
   revision = "152e9ff2c63af90874bf3eff1286acee291d0065"
   version = "v1.14.2"
 
 [[projects]]
   branch = "master"
+  digest = "1:d6afaeed1502aa28e80a4ed0981d570ad91b2579193404256ce672ed0a609e0d"
   name = "github.com/beorn7/perks"
   packages = ["quantile"]
+  pruneopts = "UT"
   revision = "3a771d992973f24aa725d07868b467d1ddfceafb"
 
 [[projects]]
+  digest = "1:2209584c0f7c9b68c23374e659357ab546e1b70eec2761f03280f69a8fd23d77"
   name = "github.com/cenkalti/backoff"
   packages = ["."]
+  pruneopts = "UT"
   revision = "2ea60e5f094469f9e65adb9cd103795b73ae743e"
   version = "v2.0.0"
 
 [[projects]]
+  digest = "1:7636c39b077a4db2b354351ae7fffad19126ef6abc66248e7ae072aad7181d60"
   name = "github.com/coreos/go-iptables"
   packages = ["iptables"]
+  pruneopts = "UT"
   revision = "b5b1876b170881a8259f036445ee89c8669db386"
   version = "v0.3.0"
 
 [[projects]]
+  digest = "1:a2c1d0e43bd3baaa071d1b9ed72c27d78169b2b269f71c105ac4ba34b1be4a39"
   name = "github.com/davecgh/go-spew"
   packages = ["spew"]
+  pruneopts = "UT"
   revision = "346938d642f2ec3594ed81d874461961cd0faa76"
   version = "v1.1.0"
 
 [[projects]]
+  digest = "1:547f5df5f708c880f0af507317c8d022b8d62053a5cb075e23c6eeed09eb2e4e"
   name = "github.com/fortytw2/leaktest"
   packages = ["."]
+  pruneopts = "UT"
   revision = "9a23578d06a26ec1b47bfc8965bf5e7011df8bd6"
   version = "v1.3.0"
 
 [[projects]]
+  digest = "1:2cd7915ab26ede7d95b8749e6b1f933f1c6d5398030684e6505940a10f31cfda"
   name = "github.com/ghodss/yaml"
   packages = ["."]
+  pruneopts = "UT"
   revision = "0ca9ea5df5451ffdf184b4428c902747c2c11cd7"
   version = "v1.0.0"
 
 [[projects]]
+  digest = "1:fb46255681497314debedde38b64be32a75bae50bad107586c22f1662bf2d352"
   name = "github.com/go-ini/ini"
   packages = ["."]
+  pruneopts = "UT"
   revision = "06f5f3d67269ccec1fe5fe4134ba6e982984f7f5"
   version = "v1.37.0"
 
 [[projects]]
+  digest = "1:a7534feda0f15b5fd691e59e4fb6b7547e27df4b415a62e02c7cb71b3439c1b1"
   name = "github.com/gogo/protobuf"
   packages = [
     "proto",
-    "sortkeys"
+    "sortkeys",
   ]
+  pruneopts = "UT"
   revision = "1adfc126b41513cc696b209667c8656ea7aac67c"
   version = "v1.0.0"
 
 [[projects]]
   branch = "master"
+  digest = "1:1ba1d79f2810270045c328ae5d674321db34e3aae468eb4233883b473c5c0467"
   name = "github.com/golang/glog"
   packages = ["."]
+  pruneopts = "UT"
   revision = "23def4e6c14b4da8ac2ed8007337bc5eb5007998"
 
 [[projects]]
   branch = "master"
+  digest = "1:3fb07f8e222402962fa190eb060608b34eddfb64562a18e2167df2de0ece85d8"
   name = "github.com/golang/groupcache"
   packages = ["lru"]
+  pruneopts = "UT"
   revision = "24b0969c4cb722950103eed87108c8d291a8df00"
 
 [[projects]]
+  digest = "1:17fe264ee908afc795734e8c4e63db2accabaf57326dbf21763a7d6b86096260"
   name = "github.com/golang/protobuf"
   packages = [
     "proto",
     "ptypes",
     "ptypes/any",
     "ptypes/duration",
-    "ptypes/timestamp"
+    "ptypes/timestamp",
   ]
+  pruneopts = "UT"
   revision = "b4deda0973fb4c70b50d226b1af49f3da59f5265"
   version = "v1.1.0"
 
 [[projects]]
   branch = "master"
+  digest = "1:3ee90c0d94da31b442dde97c99635aaafec68d0b8a3c12ee2075c6bdabeec6bb"
   name = "github.com/google/gofuzz"
   packages = ["."]
+  pruneopts = "UT"
   revision = "24818f796faf91cd76ec7bddd72458fbced7a6c1"
 
 [[projects]]
+  digest = "1:65c4414eeb350c47b8de71110150d0ea8a281835b1f386eacaa3ad7325929c21"
   name = "github.com/googleapis/gnostic"
   packages = [
     "OpenAPIv2",
     "compiler",
-    "extensions"
+    "extensions",
   ]
+  pruneopts = "UT"
   revision = "7c663266750e7d82587642f65e60bc4083f1f84e"
   version = "v0.2.0"
 
 [[projects]]
+  digest = "1:c79fb010be38a59d657c48c6ba1d003a8aa651fa56b579d959d74573b7dff8e1"
   name = "github.com/gorilla/context"
   packages = ["."]
+  pruneopts = "UT"
   revision = "08b5f424b9271eedf6f9f0ce86cb9396ed337a42"
   version = "v1.1.1"
 
 [[projects]]
+  digest = "1:e73f5b0152105f18bc131fba127d9949305c8693f8a762588a82a48f61756f5f"
   name = "github.com/gorilla/mux"
   packages = ["."]
+  pruneopts = "UT"
   revision = "e3702bed27f0d39777b0b37b664b6280e8ef8fbf"
   version = "v1.6.2"
 
 [[projects]]
+  digest = "1:73513cdd52d6f0768201cebbf82612aa39a9d8022bc6337815cd504e532281b7"
   name = "github.com/grpc-ecosystem/go-grpc-middleware"
   packages = [
     ".",
     "retry",
     "util/backoffutils",
-    "util/metautils"
+    "util/metautils",
   ]
+  pruneopts = "UT"
   revision = "c250d6563d4d4c20252cd865923440e829844f4e"
   version = "v1.0.0"
 
 [[projects]]
+  digest = "1:9b7a07ac7577787a8ecc1334cb9f34df1c76ed82a917d556c5713d3ab84fbc43"
   name = "github.com/grpc-ecosystem/go-grpc-prometheus"
   packages = ["."]
+  pruneopts = "UT"
   revision = "c225b8c3b01faf2899099b768856a9e916e5087b"
   version = "v1.2.0"
 
 [[projects]]
   branch = "master"
+  digest = "1:cf296baa185baae04a9a7004efee8511d08e2f5f51d4cbe5375da89722d681db"
   name = "github.com/hashicorp/golang-lru"
   packages = [
     ".",
-    "simplelru"
+    "simplelru",
   ]
+  pruneopts = "UT"
   revision = "0fb14efe8c47ae851c0034ed7a448854d3d34cf3"
 
 [[projects]]
   branch = "master"
+  digest = "1:0778dc7fce1b4669a8bfa7ae506ec1f595b6ab0f8989c1c0d22a8ca1144e9972"
   name = "github.com/howeyc/gopass"
   packages = ["."]
+  pruneopts = "UT"
   revision = "bf9dde6d0d2c004a008c27aaee91170c786f6db8"
 
 [[projects]]
+  digest = "1:b39dba8363bf11da3cddcc31c5a9c39f17fba8a5317ae0836ea4530bae3b4866"
   name = "github.com/imdario/mergo"
   packages = ["."]
+  pruneopts = "UT"
   revision = "9d5f1277e9a8ed20c3684bda8fde67c05628518c"
   version = "v0.3.4"
 
 [[projects]]
+  digest = "1:e22af8c7518e1eab6f2eab2b7d7558927f816262586cd6ed9f349c97a6c285c4"
   name = "github.com/jmespath/go-jmespath"
   packages = ["."]
+  pruneopts = "UT"
   revision = "0b12d6b5"
 
 [[projects]]
+  digest = "1:b1d4df033414c1a0d85fa7037b9aaf03746314811c860a95ea2d5fd481cd6c35"
   name = "github.com/json-iterator/go"
   packages = ["."]
+  pruneopts = "UT"
   revision = "ca39e5af3ece67bbcda3d0f4f56a8e24d9f2dad4"
   version = "1.1.3"
 
 [[projects]]
+  digest = "1:ff5ebae34cfbf047d505ee150de27e60570e8c394b3b8fdbb720ff6ac71985fc"
   name = "github.com/matttproud/golang_protobuf_extensions"
   packages = ["pbutil"]
+  pruneopts = "UT"
   revision = "c12348ce28de40eed0136aa2b644d0ee0650e56c"
   version = "v1.0.1"
 
 [[projects]]
+  digest = "1:33422d238f147d247752996a26574ac48dcf472976eda7f5134015f06bf16563"
   name = "github.com/modern-go/concurrent"
   packages = ["."]
+  pruneopts = "UT"
   revision = "bacd9c7ef1dd9b15be4a9909b8ac7a4e313eec94"
   version = "1.0.3"
 
 [[projects]]
+  digest = "1:d711dfcf661439f1ef0b202a02e8a1ff4deac48f26f34253520dcdbecbd7c5f1"
   name = "github.com/modern-go/reflect2"
   packages = ["."]
+  pruneopts = "UT"
   revision = "1df9eeb2bb81f327b96228865c5687bc2194af3f"
   version = "1.0.0"
 
 [[projects]]
+  digest = "1:808cdddf087fb64baeae67b8dfaee2069034d9704923a3cb8bd96a995421a625"
   name = "github.com/patrickmn/go-cache"
   packages = ["."]
+  pruneopts = "UT"
   revision = "a3647f8e31d79543b2d0f0ae2fe5c379d72cedc0"
   version = "v2.1.0"
 
 [[projects]]
+  digest = "1:c968b29db5d68ec97de404b6d058d5937fa015a141b3b4f7a0d87d5f8226f04c"
   name = "github.com/prometheus/client_golang"
   packages = [
     "prometheus",
-    "prometheus/promhttp"
+    "prometheus/promhttp",
   ]
+  pruneopts = "UT"
   revision = "967789050ba94deca04a5e84cce8ad472ce313c1"
   version = "v0.9.0-pre1"
 
 [[projects]]
   branch = "master"
+  digest = "1:32d10bdfa8f09ecf13598324dba86ab891f11db3c538b6a34d1c3b5b99d7c36b"
   name = "github.com/prometheus/client_model"
   packages = ["go"]
+  pruneopts = "UT"
   revision = "99fa1f4be8e564e8a6b613da7fa6f46c9edafc6c"
 
 [[projects]]
   branch = "master"
+  digest = "1:e469cd65badf7694aeb44874518606d93c1d59e7735d3754ad442782437d3cc3"
   name = "github.com/prometheus/common"
   packages = [
     "expfmt",
     "internal/bitbucket.org/ww/goautoneg",
-    "model"
+    "model",
   ]
+  pruneopts = "UT"
   revision = "7600349dcfe1abd18d72d3a1770870d9800a7801"
 
 [[projects]]
   branch = "master"
+  digest = "1:570784e0ddbf67f14087c6d8cfb7b999b9c55e75518a755e88cb202566ea8a17"
   name = "github.com/prometheus/procfs"
   packages = [
     ".",
     "internal/util",
     "nfs",
-    "xfs"
+    "xfs",
   ]
+  pruneopts = "UT"
   revision = "94663424ae5ae9856b40a9f170762b4197024661"
 
 [[projects]]
+  digest = "1:9e9193aa51197513b3abcb108970d831fbcf40ef96aa845c4f03276e1fa316d2"
   name = "github.com/sirupsen/logrus"
   packages = ["."]
+  pruneopts = "UT"
   revision = "c155da19408a8799da419ed3eeb0cb5db0ad5dbc"
   version = "v1.0.5"
 
 [[projects]]
+  digest = "1:9424f440bba8f7508b69414634aef3b2b3a877e522d8a4624692412805407bb7"
   name = "github.com/spf13/pflag"
   packages = ["."]
+  pruneopts = "UT"
   revision = "583c0c0531f06d5278b7d917446061adc344b5cd"
   version = "v1.0.1"
 
 [[projects]]
   branch = "master"
+  digest = "1:98f6a362abd5243869a33702d068e56342439a223fa5145f2e9b574e4970b3cc"
   name = "github.com/uswitch/k8sc"
   packages = ["official"]
+  pruneopts = "UT"
   revision = "475c8175b34078cf65b89a5660f1e5a921c9c773"
 
 [[projects]]
+  digest = "1:dd1a3f5a0d4ec27669062b10013515233c4fef35b876f339d838495d0c8d6b67"
   name = "github.com/vmg/backoff"
   packages = ["."]
+  pruneopts = "UT"
   revision = "32cd0c5b3aef12c76ed64aaf678f6c79736be7dc"
   version = "v1.0.0"
 
 [[projects]]
   branch = "master"
+  digest = "1:3f3a05ae0b95893d90b9b3b5afdb79a9b3d96e4e36e099d841ae602e4aca0da8"
   name = "golang.org/x/crypto"
   packages = ["ssh/terminal"]
+  pruneopts = "UT"
   revision = "8ac0e0d97ce45cd83d1d7243c060cb8461dda5e9"
 
 [[projects]]
   branch = "master"
+  digest = "1:018091dab17e9cddf15d7706a6b50e26e6b05e125307a027699a4f862651f047"
   name = "golang.org/x/net"
   packages = [
     "context",
@@ -301,20 +378,24 @@
     "http2/hpack",
     "idna",
     "internal/timeseries",
-    "trace"
+    "trace",
   ]
+  pruneopts = "UT"
   revision = "1e491301e022f8f977054da4c2d852decd59571f"
 
 [[projects]]
   branch = "master"
+  digest = "1:8fbfc6ea1a8a078697633be97f07dd83a83d32a96959d42195464c13c25be374"
   name = "golang.org/x/sys"
   packages = [
     "unix",
-    "windows"
+    "windows",
   ]
+  pruneopts = "UT"
   revision = "9527bec2660bd847c050fda93a0f0c6dee0800bb"
 
 [[projects]]
+  digest = "1:a2ab62866c75542dd18d2b069fec854577a20211d7c0ea6ae746072a1dccdd18"
   name = "golang.org/x/text"
   packages = [
     "collate",
@@ -330,41 +411,53 @@
     "unicode/bidi",
     "unicode/cldr",
     "unicode/norm",
-    "unicode/rangetable"
+    "unicode/rangetable",
   ]
+  pruneopts = "UT"
   revision = "f21a4dfb5e38f5895301dc265a8def02365cc3d0"
   version = "v0.3.0"
 
 [[projects]]
   branch = "master"
+  digest = "1:c9e7a4b4d47c0ed205d257648b0e5b0440880cb728506e318f8ac7cd36270bc4"
   name = "golang.org/x/time"
   packages = ["rate"]
+  pruneopts = "UT"
   revision = "fbb02b2291d28baffd63558aa44b4b56f178d650"
 
 [[projects]]
   branch = "master"
+  digest = "1:3c24554c312721e98fa6b76403e7100cf974eb46b1255ea7fc6471db9a9ce498"
   name = "google.golang.org/genproto"
   packages = ["googleapis/rpc/status"]
+  pruneopts = "UT"
   revision = "81158efcc9f219c511e4d3c0d61a0e6e49c01a24"
 
 [[projects]]
+  digest = "1:3b97661db2e5d4c87f7345e875ea28f911e54c715ba0a74be08e1649d67e05cd"
   name = "google.golang.org/grpc"
   packages = [
     ".",
     "balancer",
     "balancer/base",
     "balancer/roundrobin",
+    "binarylog/grpc_binarylog_v1",
     "codes",
     "connectivity",
     "credentials",
+    "credentials/internal",
     "encoding",
     "encoding/proto",
     "grpclog",
     "internal",
     "internal/backoff",
+    "internal/balancerload",
+    "internal/binarylog",
     "internal/channelz",
     "internal/envconfig",
     "internal/grpcrand",
+    "internal/grpcsync",
+    "internal/syscall",
     "internal/transport",
     "keepalive",
     "metadata",
@@ -373,38 +466,49 @@
     "resolver",
     "resolver/dns",
     "resolver/passthrough",
+    "serviceconfig",
     "stats",
     "status",
-    "tap"
+    "tap",
   ]
-  revision = "32fb0ac620c32ba40a4626ddf94d90d12cce3455"
-  version = "v1.14.0"
+  pruneopts = "UT"
+  revision = "6eaf6f47437a6b4e2153a190160ef39a92c7eceb"
+  version = "v1.23.0"
 
 [[projects]]
+  digest = "1:c06d9e11d955af78ac3bbb26bd02e01d2f61f689e1a3bce2ef6fb683ef8a7f2d"
   name = "gopkg.in/alecthomas/kingpin.v2"
   packages = ["."]
+  pruneopts = "UT"
   revision = "947dcec5ba9c011838740e680966fd7087a71d0d"
   version = "v2.2.6"
 
 [[projects]]
+  digest = "1:38b469493eb173db9c03321d64adcad4c7991ea0a19b5edc5bdc094f0e8c7384"
   name = "gopkg.in/alexcesaro/statsd.v2"
   packages = ["."]
+  pruneopts = "UT"
   revision = "7fea3f0d2fab1ad973e641e51dba45443a311a90"
   version = "v2.0.0"
 
 [[projects]]
+  digest = "1:2d1fbdc6777e5408cabeb02bf336305e724b925ff4546ded0fa8715a7267922a"
   name = "gopkg.in/inf.v0"
   packages = ["."]
+  pruneopts = "UT"
   revision = "d2d2541c53f18d2a059457998ce2876cc8e67cbf"
   version = "v0.9.1"
 
 [[projects]]
+  digest = "1:342378ac4dcb378a5448dd723f0784ae519383532f5e70ade24132c4c8693202"
   name = "gopkg.in/yaml.v2"
   packages = ["."]
+  pruneopts = "UT"
   revision = "5420a8b6744d3b0345ab293f6fcba19c978f1183"
   version = "v2.2.1"
 
 [[projects]]
+  digest = "1:1537dffcab6c5ed740c06e16df243a39a54bc69e0d221271e6da4b235160ceab"
   name = "k8s.io/api"
   packages = [
     "admissionregistration/v1alpha1",
@@ -434,12 +538,14 @@
     "settings/v1alpha1",
     "storage/v1",
     "storage/v1alpha1",
-    "storage/v1beta1"
+    "storage/v1beta1",
   ]
+  pruneopts = "UT"
   revision = "feb48db456a5912850dcccbd42a3535382ba76de"
   version = "kubernetes-1.10.3"
 
 [[projects]]
+  digest = "1:6cb2908493b272960f263f4dffad5db79590aae090bd83468373b641638e4209"
   name = "k8s.io/apimachinery"
   packages = [
     "pkg/api/errors",
@@ -482,12 +588,14 @@
     "pkg/version",
     "pkg/watch",
     "third_party/forked/golang/json",
-    "third_party/forked/golang/reflect"
+    "third_party/forked/golang/reflect",
   ]
+  pruneopts = "UT"
   revision = "31dade610c053669d8054bfd847da657251e8c1a"
   version = "kubernetes-1.10.3"
 
 [[projects]]
+  digest = "1:65ce0ad8c865cd1a87c3af5bed4859e1a2c8077d23a96f3eae6b5e9a38225c62"
   name = "k8s.io/client-go"
   packages = [
     "discovery",
@@ -544,20 +652,62 @@
     "util/flowcontrol",
     "util/homedir",
     "util/integer",
-    "util/retry"
+    "util/retry",
   ]
+  pruneopts = "UT"
   revision = "23781f4d6632d88e869066eaebb743857aa1ef9b"
   version = "v7.0.0"
 
 [[projects]]
   branch = "master"
+  digest = "1:a2c842a1e0aed96fd732b535514556323a6f5edfded3b63e5e0ab1bce188aa54"
   name = "k8s.io/kube-openapi"
   packages = ["pkg/util/proto"]
+  pruneopts = "UT"
   revision = "d83b052f768a50a309c692a9c271da3f3276ff88"
 
 [solve-meta]
   analyzer-name = "dep"
   analyzer-version = 1
-  inputs-digest = "b4579c4afb897651187b6fd07319642665ccf1641c0af462e6fe3feced576c75"
+  input-imports = [
+    "github.com/aws/aws-sdk-go/aws",
+    "github.com/aws/aws-sdk-go/aws/awserr",
+    "github.com/aws/aws-sdk-go/aws/credentials/stscreds",
+    "github.com/aws/aws-sdk-go/aws/ec2metadata",
+    "github.com/aws/aws-sdk-go/aws/endpoints",
+    "github.com/aws/aws-sdk-go/aws/session",
+    "github.com/aws/aws-sdk-go/service/sts",
+    "github.com/cenkalti/backoff",
+    "github.com/coreos/go-iptables/iptables",
+    "github.com/fortytw2/leaktest",
+    "github.com/golang/protobuf/proto",
+    "github.com/gorilla/mux",
+    "github.com/grpc-ecosystem/go-grpc-middleware",
+    "github.com/grpc-ecosystem/go-grpc-middleware/retry",
+    "github.com/grpc-ecosystem/go-grpc-prometheus",
+    "github.com/patrickmn/go-cache",
+    "github.com/prometheus/client_golang/prometheus",
+    "github.com/prometheus/client_golang/prometheus/promhttp",
+    "github.com/sirupsen/logrus",
+    "github.com/uswitch/k8sc/official",
+    "github.com/vmg/backoff",
+    "golang.org/x/net/context",
+    "google.golang.org/grpc",
+    "google.golang.org/grpc/balancer/roundrobin",
+    "google.golang.org/grpc/credentials",
+    "google.golang.org/grpc/status",
+    "gopkg.in/alecthomas/kingpin.v2",
+    "gopkg.in/alexcesaro/statsd.v2",
+    "k8s.io/api/core/v1",
+    "k8s.io/apimachinery/pkg/apis/meta/v1",
+    "k8s.io/apimachinery/pkg/fields",
+    "k8s.io/apimachinery/pkg/runtime",
+    "k8s.io/client-go/kubernetes",
+    "k8s.io/client-go/kubernetes/scheme",
+    "k8s.io/client-go/kubernetes/typed/core/v1",
+    "k8s.io/client-go/tools/cache",
+    "k8s.io/client-go/tools/cache/testing",
+    "k8s.io/client-go/tools/record",
+  ]
   solver-name = "gps-cdcl"
   solver-version = 1
diff --git a/Gopkg.toml b/Gopkg.toml
index 5aa8cc07..6b63d0c8 100644
--- a/Gopkg.toml
+++ b/Gopkg.toml
@@ -75,7 +75,7 @@
 
 [[constraint]]
   name = "google.golang.org/grpc"
-  version = "1.14.0"
+  version = "1.23.0"
 
 [[constraint]]
   name = "gopkg.in/alecthomas/kingpin.v2"
diff --git a/pkg/server/gateway.go b/pkg/server/gateway.go
index d48a9f7b..fde55479 100644
--- a/pkg/server/gateway.go
+++ b/pkg/server/gateway.go
@@ -90,7 +90,6 @@ func NewGateway(ctx context.Context, address string, caFile, certificateFile, ke
 		grpc.WithBalancerName(roundrobin.Name),
 		grpc.WithDisableServiceConfig(),
 		grpc.WithBlock(),
-		grpc.WithWaitForHandshake(),
 		grpc.WithStreamInterceptor(grpc_prometheus.StreamClientInterceptor),
 	}
 	conn, err := grpc.DialContext(ctx, dialAddress, dialOpts...)
diff --git a/vendor/google.golang.org/grpc/.travis.yml b/vendor/google.golang.org/grpc/.travis.yml
index 5b5bfb13..024408e6 100644
--- a/vendor/google.golang.org/grpc/.travis.yml
+++ b/vendor/google.golang.org/grpc/.travis.yml
@@ -2,33 +2,38 @@ language: go
 
 matrix:
   include:
+  - go: 1.12.x
+    env: VET=1 GO111MODULE=on
+  - go: 1.12.x
+    env: RACE=1 GO111MODULE=on
+  - go: 1.12.x
+    env: RUN386=1
+  - go: 1.12.x
+    env: GRPC_GO_RETRY=on
+  - go: 1.11.x
+    env: GO111MODULE=on
   - go: 1.10.x
-    env: VET=1 RACE=1
-  - go: 1.6.x
-  - go: 1.7.x
-  - go: 1.8.x
   - go: 1.9.x
   - go: 1.9.x
     env: GAE=1
-  - go: 1.10.x
-    env: RUN386=1
-  - go: 1.10.x
-    env: GRPC_GO_RETRY=on
 
 go_import_path: google.golang.org/grpc
 
 before_install:
-  - if [[ -n "$RUN386" ]]; then export GOARCH=386; fi
-  - if [[ "$TRAVIS_EVENT_TYPE" = "cron" && -z "$RUN386" ]]; then RACE=1; fi
-  - if [[ "$TRAVIS_EVENT_TYPE" != "cron" ]]; then VET_SKIP_PROTO=1; fi
+  - if [[ "${GO111MODULE}" = "on" ]]; then mkdir "${HOME}/go"; export GOPATH="${HOME}/go"; fi
+  - if [[ -n "${RUN386}" ]]; then export GOARCH=386; fi
+  - if [[ "${TRAVIS_EVENT_TYPE}" = "cron" && -z "${RUN386}" ]]; then RACE=1; fi
+  - if [[ "${TRAVIS_EVENT_TYPE}" != "cron" ]]; then VET_SKIP_PROTO=1; fi
 
 install:
-  - if [[ "$GAE" = 1 ]]; then source ./install_gae.sh; fi
-  - if [[ "$VET" = 1 ]]; then ./vet.sh -install; fi
+  - try3() { eval "$*" || eval "$*" || eval "$*"; }
+  - try3 'if [[ "${GO111MODULE}" = "on" ]]; then go mod download; else make testdeps; fi'
+  - if [[ "${GAE}" = 1 ]]; then source ./install_gae.sh; make testappenginedeps; fi
+  - if [[ "${VET}" = 1 ]]; then ./vet.sh -install; fi
 
 script:
   - set -e
-  - if [[ "$GAE" = 1 ]]; then make testappengine; exit 0; fi
-  - if [[ "$VET" = 1 ]]; then ./vet.sh; fi
+  - if [[ "${VET}" = 1 ]]; then ./vet.sh; fi
+  - if [[ "${GAE}" = 1 ]]; then make testappengine; exit 0; fi
+  - if [[ "${RACE}" = 1 ]]; then make testrace; exit 0; fi
   - make test
-  - if [[ "$RACE" = 1 ]]; then make testrace; fi
diff --git a/vendor/google.golang.org/grpc/CONTRIBUTING.md b/vendor/google.golang.org/grpc/CONTRIBUTING.md
index 0863eb26..6e69b28c 100644
--- a/vendor/google.golang.org/grpc/CONTRIBUTING.md
+++ b/vendor/google.golang.org/grpc/CONTRIBUTING.md
@@ -11,26 +11,50 @@ In order to protect both you and ourselves, you will need to sign the
 
 ## Guidelines for Pull Requests
 How to get your contributions merged smoothly and quickly.
- 
-- Create **small PRs** that are narrowly focused on **addressing a single concern**. We often times receive PRs that are trying to fix several things at a time, but only one fix is considered acceptable, nothing gets merged and both author's & review's time is wasted. Create more PRs to address different concerns and everyone will be happy.
- 
-- For speculative changes, consider opening an issue and discussing it first. If you are suggesting a behavioral or API change, consider starting with a [gRFC proposal](https://github.com/grpc/proposal). 
- 
-- Provide a good **PR description** as a record of **what** change is being made and **why** it was made. Link to a github issue if it exists.
- 
-- Don't fix code style and formatting unless you are already changing that line to address an issue. PRs with irrelevant changes won't be merged. If you do want to fix formatting or style, do that in a separate PR.
- 
-- Unless your PR is trivial, you should expect there will be reviewer comments that you'll need to address before merging. We expect you to be reasonably responsive to those comments, otherwise the PR will be closed after 2-3 weeks of inactivity.
- 
-- Maintain **clean commit history** and use **meaningful commit messages**. PRs with messy commit history are difficult to review and won't be merged. Use `rebase -i upstream/master` to curate your commit history and/or to bring in latest changes from master (but avoid rebasing in the middle of a code review).
- 
-- Keep your PR up to date with upstream/master (if there are merge conflicts, we can't really merge your change).
- 
-- **All tests need to be passing** before your change can be merged. We recommend you **run tests locally** before creating your PR to catch breakages early on.
+
+- Create **small PRs** that are narrowly focused on **addressing a single
+  concern**. We often times receive PRs that are trying to fix several things at
+  a time, but only one fix is considered acceptable, nothing gets merged and
+  both author's & review's time is wasted. Create more PRs to address different
+  concerns and everyone will be happy.
+
+- The grpc package should only depend on standard Go packages and a small number
+  of exceptions. If your contribution introduces new dependencies which are NOT
+  in the [list](https://godoc.org/google.golang.org/grpc?imports), you need a
+  discussion with gRPC-Go authors and consultants.
+
+- For speculative changes, consider opening an issue and discussing it first. If
+  you are suggesting a behavioral or API change, consider starting with a [gRFC
+  proposal](https://github.com/grpc/proposal).
+
+- Provide a good **PR description** as a record of **what** change is being made
+  and **why** it was made. Link to a github issue if it exists.
+
+- Don't fix code style and formatting unless you are already changing that line
+  to address an issue. PRs with irrelevant changes won't be merged. If you do
+  want to fix formatting or style, do that in a separate PR.
+
+- Unless your PR is trivial, you should expect there will be reviewer comments
+  that you'll need to address before merging. We expect you to be reasonably
+  responsive to those comments, otherwise the PR will be closed after 2-3 weeks
+  of inactivity.
+
+- Maintain **clean commit history** and use **meaningful commit messages**. PRs
+  with messy commit history are difficult to review and won't be merged. Use
+  `rebase -i upstream/master` to curate your commit history and/or to bring in
+  latest changes from master (but avoid rebasing in the middle of a code
+  review).
+
+- Keep your PR up to date with upstream/master (if there are merge conflicts, we
+  can't really merge your change).
+
+- **All tests need to be passing** before your change can be merged. We
+  recommend you **run tests locally** before creating your PR to catch breakages
+  early on.
   - `make all` to test everything, OR
   - `make vet` to catch vet errors
   - `make test` to run the tests
   - `make testrace` to run tests in race mode
+  - optional `make testappengine` to run tests with appengine
 
 - Exceptions to the rules can be made if there's a compelling reason for doing so.
- 
diff --git a/vendor/google.golang.org/grpc/Makefile b/vendor/google.golang.org/grpc/Makefile
index 50454530..db982aab 100644
--- a/vendor/google.golang.org/grpc/Makefile
+++ b/vendor/google.golang.org/grpc/Makefile
@@ -1,23 +1,14 @@
 all: vet test testrace
 
-deps:
-	go get -d -v google.golang.org/grpc/...
-
-updatedeps:
-	go get -d -v -u -f google.golang.org/grpc/...
-
-testdeps:
-	go get -d -v -t google.golang.org/grpc/...
-
-testgaedeps:
-	goapp get -d -v -t -tags 'appengine appenginevm' google.golang.org/grpc/...
-
-updatetestdeps:
-	go get -d -v -t -u -f google.golang.org/grpc/...
-
 build: deps
 	go build google.golang.org/grpc/...
 
+clean:
+	go clean -i google.golang.org/grpc/...
+
+deps:
+	go get -d -v google.golang.org/grpc/...
+
 proto:
 	@ if ! which protoc > /dev/null; then \
 		echo "error: protoc not installed" >&2; \
@@ -25,31 +16,45 @@ proto:
 	fi
 	go generate google.golang.org/grpc/...
 
-vet:
-	./vet.sh
-
 test: testdeps
-	go test -cpu 1,4 -timeout 5m google.golang.org/grpc/...
+	go test -cpu 1,4 -timeout 7m google.golang.org/grpc/...
+
+testappengine: testappenginedeps
+	goapp test -cpu 1,4 -timeout 7m google.golang.org/grpc/...
+
+testappenginedeps:
+	goapp get -d -v -t -tags 'appengine appenginevm' google.golang.org/grpc/...
+
+testdeps:
+	go get -d -v -t google.golang.org/grpc/...
 
 testrace: testdeps
 	go test -race -cpu 1,4 -timeout 7m google.golang.org/grpc/...
 
-testappengine: testgaedeps
-	goapp test -cpu 1,4 -timeout 5m google.golang.org/grpc/...
+updatedeps:
+	go get -d -v -u -f google.golang.org/grpc/...
+
+updatetestdeps:
+	go get -d -v -t -u -f google.golang.org/grpc/...
 
-clean:
-	go clean -i google.golang.org/grpc/...
+vet: vetdeps
+	./vet.sh
+
+vetdeps:
+	./vet.sh -install
 
 .PHONY: \
 	all \
-	deps \
-	updatedeps \
-	testdeps \
-	testgaedeps \
-	updatetestdeps \
 	build \
+	clean \
+	deps \
 	proto \
-	vet \
 	test \
+	testappengine \
+	testappenginedeps \
+	testdeps \
 	testrace \
-	clean
+	updatedeps \
+	updatetestdeps \
+	vet \
+	vetdeps
diff --git a/vendor/google.golang.org/grpc/README.md b/vendor/google.golang.org/grpc/README.md
index 789adfd6..afbc43db 100644
--- a/vendor/google.golang.org/grpc/README.md
+++ b/vendor/google.golang.org/grpc/README.md
@@ -1,45 +1,121 @@
 # gRPC-Go
 
-[![Build Status](https://travis-ci.org/grpc/grpc-go.svg)](https://travis-ci.org/grpc/grpc-go) [![GoDoc](https://godoc.org/google.golang.org/grpc?status.svg)](https://godoc.org/google.golang.org/grpc) [![GoReportCard](https://goreportcard.com/badge/grpc/grpc-go)](https://goreportcard.com/report/github.com/grpc/grpc-go)
+[![Build Status](https://travis-ci.org/grpc/grpc-go.svg)](https://travis-ci.org/grpc/grpc-go)
+[![GoDoc](https://godoc.org/google.golang.org/grpc?status.svg)](https://godoc.org/google.golang.org/grpc)
+[![GoReportCard](https://goreportcard.com/badge/grpc/grpc-go)](https://goreportcard.com/report/github.com/grpc/grpc-go)
 
-The Go implementation of [gRPC](https://grpc.io/): A high performance, open source, general RPC framework that puts mobile and HTTP/2 first. For more information see the [gRPC Quick Start: Go](https://grpc.io/docs/quickstart/go.html) guide.
+The Go implementation of [gRPC](https://grpc.io/): A high performance, open
+source, general RPC framework that puts mobile and HTTP/2 first. For more
+information see the [gRPC Quick Start:
+Go](https://grpc.io/docs/quickstart/go.html) guide.
 
 Installation
 ------------
 
-To install this package, you need to install Go and setup your Go workspace on your computer. The simplest way to install the library is to run:
+To install this package, you need to install Go and setup your Go workspace on
+your computer. The simplest way to install the library is to run:
 
 ```
 $ go get -u google.golang.org/grpc
 ```
 
-Prerequisites
--------------
+With Go module support (Go 1.11+), simply `import "google.golang.org/grpc"` in
+your source code and `go [build|run|test]` will automatically download the
+necessary dependencies ([Go modules
+ref](https://github.com/golang/go/wiki/Modules)).
 
-This requires Go 1.6 or later. Go 1.7 will be required soon.
+If you are trying to access grpc-go from within China, please see the
+[FAQ](#FAQ) below.
 
-Constraints
------------
-The grpc package should only depend on standard Go packages and a small number of exceptions. If your contribution introduces new dependencies which are NOT in the [list](http://godoc.org/google.golang.org/grpc?imports), you need a discussion with gRPC-Go authors and consultants.
+Prerequisites
+-------------
+gRPC-Go requires Go 1.9 or later.
 
 Documentation
 -------------
-See [API documentation](https://godoc.org/google.golang.org/grpc) for package and API descriptions and find examples in the [examples directory](examples/).
+- See [godoc](https://godoc.org/google.golang.org/grpc) for package and API
+  descriptions.
+- Documentation on specific topics can be found in the [Documentation
+  directory](Documentation/).
+- Examples can be found in the [examples directory](examples/).
 
 Performance
 -----------
-See the current benchmarks for some of the languages supported in [this dashboard](https://performance-dot-grpc-testing.appspot.com/explore?dashboard=5652536396611584&widget=490377658&container=1286539696).
+Performance benchmark data for grpc-go and other languages is maintained in
+[this
+dashboard](https://performance-dot-grpc-testing.appspot.com/explore?dashboard=5652536396611584&widget=490377658&container=1286539696).
 
 Status
 ------
-General Availability [Google Cloud Platform Launch Stages](https://cloud.google.com/terms/launch-stages).
+General Availability [Google Cloud Platform Launch
+Stages](https://cloud.google.com/terms/launch-stages).
 
 FAQ
 ---
 
+#### I/O Timeout Errors
+
+The `golang.org` domain may be blocked from some countries.  `go get` usually
+produces an error like the following when this happens:
+
+```
+$ go get -u google.golang.org/grpc
+package google.golang.org/grpc: unrecognized import path "google.golang.org/grpc" (https fetch: Get https://google.golang.org/grpc?go-get=1: dial tcp 216.239.37.1:443: i/o timeout)
+```
+
+To build Go code, there are several options:
+
+- Set up a VPN and access google.golang.org through that.
+
+- Without Go module support: `git clone` the repo manually:
+
+  ```
+  git clone https://github.com/grpc/grpc-go.git $GOPATH/src/google.golang.org/grpc
+  ```
+
+  You will need to do the same for all of grpc's dependencies in `golang.org`,
+  e.g. `golang.org/x/net`.
+
+- With Go module support: it is possible to use the `replace` feature of `go
+  mod` to create aliases for golang.org packages.  In your project's directory:
+
+  ```
+  go mod edit -replace=google.golang.org/grpc=github.com/grpc/grpc-go@latest
+  go mod tidy
+  go mod vendor
+  go build -mod=vendor
+  ```
+
+  Again, this will need to be done for all transitive dependencies hosted on
+  golang.org as well.  Please refer to [this
+  issue](https://github.com/golang/go/issues/28652) in the golang repo regarding
+  this concern.
+
 #### Compiling error, undefined: grpc.SupportPackageIsVersion
 
 Please update proto package, gRPC package and rebuild the proto files:
  - `go get -u github.com/golang/protobuf/{proto,protoc-gen-go}`
  - `go get -u google.golang.org/grpc`
  - `protoc --go_out=plugins=grpc:. *.proto`
+
+#### How to turn on logging
+
+The default logger is controlled by the environment variables. Turn everything
+on by setting:
+
+```
+GRPC_GO_LOG_VERBOSITY_LEVEL=99 GRPC_GO_LOG_SEVERITY_LEVEL=info
+```
+
+#### The RPC failed with error `"code = Unavailable desc = transport is closing"`
+
+This error means the connection the RPC is using was closed, and there are many
+possible reasons, including:
+ 1. mis-configured transport credentials, connection failed on handshaking
+ 1. bytes disrupted, possibly by a proxy in between
+ 1. server shutdown
+
+It can be tricky to debug this because the error happens on the client side but
+the root cause of the connection being closed is on the server side. Turn on
+logging on __both client and server__, and see if there are any transport
+errors.
diff --git a/vendor/google.golang.org/grpc/backoff.go b/vendor/google.golang.org/grpc/backoff.go
index fa31565f..97c6e256 100644
--- a/vendor/google.golang.org/grpc/backoff.go
+++ b/vendor/google.golang.org/grpc/backoff.go
@@ -17,7 +17,7 @@
  */
 
 // See internal/backoff package for the backoff implementation. This file is
-// kept for the exported types and API backward compatility.
+// kept for the exported types and API backward compatibility.
 
 package grpc
 
diff --git a/vendor/google.golang.org/grpc/balancer.go b/vendor/google.golang.org/grpc/balancer.go
index e1730166..a8eb0f47 100644
--- a/vendor/google.golang.org/grpc/balancer.go
+++ b/vendor/google.golang.org/grpc/balancer.go
@@ -19,11 +19,10 @@
 package grpc
 
 import (
-	"fmt"
+	"context"
 	"net"
 	"sync"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
@@ -44,7 +43,7 @@ type Address struct {
 
 // BalancerConfig specifies the configurations for Balancer.
 //
-// Deprecated: please use package balancer.
+// Deprecated: please use package balancer.  May be removed in a future 1.x release.
 type BalancerConfig struct {
 	// DialCreds is the transport credential the Balancer implementation can
 	// use to dial to a remote load balancer server. The Balancer implementations
@@ -58,7 +57,7 @@ type BalancerConfig struct {
 
 // BalancerGetOptions configures a Get call.
 //
-// Deprecated: please use package balancer.
+// Deprecated: please use package balancer.  May be removed in a future 1.x release.
 type BalancerGetOptions struct {
 	// BlockingWait specifies whether Get should block when there is no
 	// connected address.
@@ -67,7 +66,7 @@ type BalancerGetOptions struct {
 
 // Balancer chooses network addresses for RPCs.
 //
-// Deprecated: please use package balancer.
+// Deprecated: please use package balancer.  May be removed in a future 1.x release.
 type Balancer interface {
 	// Start does the initialization work to bootstrap a Balancer. For example,
 	// this function may start the name resolution and watch the updates. It will
@@ -118,30 +117,10 @@ type Balancer interface {
 	Close() error
 }
 
-// downErr implements net.Error. It is constructed by gRPC internals and passed to the down
-// call of Balancer.
-type downErr struct {
-	timeout   bool
-	temporary bool
-	desc      string
-}
-
-func (e downErr) Error() string   { return e.desc }
-func (e downErr) Timeout() bool   { return e.timeout }
-func (e downErr) Temporary() bool { return e.temporary }
-
-func downErrorf(timeout, temporary bool, format string, a ...interface{}) downErr {
-	return downErr{
-		timeout:   timeout,
-		temporary: temporary,
-		desc:      fmt.Sprintf(format, a...),
-	}
-}
-
 // RoundRobin returns a Balancer that selects addresses round-robin. It uses r to watch
 // the name resolution updates and updates the addresses available correspondingly.
 //
-// Deprecated: please use package balancer/roundrobin.
+// Deprecated: please use package balancer/roundrobin. May be removed in a future 1.x release.
 func RoundRobin(r naming.Resolver) Balancer {
 	return &roundRobin{r: r}
 }
@@ -410,7 +389,3 @@ func (rr *roundRobin) Close() error {
 type pickFirst struct {
 	*roundRobin
 }
-
-func pickFirstBalancerV1(r naming.Resolver) Balancer {
-	return &pickFirst{&roundRobin{r: r}}
-}
diff --git a/vendor/google.golang.org/grpc/balancer/balancer.go b/vendor/google.golang.org/grpc/balancer/balancer.go
index 069feb1e..c266f4ec 100644
--- a/vendor/google.golang.org/grpc/balancer/balancer.go
+++ b/vendor/google.golang.org/grpc/balancer/balancer.go
@@ -21,14 +21,18 @@
 package balancer
 
 import (
+	"context"
+	"encoding/json"
 	"errors"
 	"net"
 	"strings"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/connectivity"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/internal"
+	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/resolver"
+	"google.golang.org/grpc/serviceconfig"
 )
 
 var (
@@ -37,7 +41,10 @@ var (
 )
 
 // Register registers the balancer builder to the balancer map. b.Name
-// (lowercased) will be used as the name registered with this builder.
+// (lowercased) will be used as the name registered with this builder.  If the
+// Builder implements ConfigParser, ParseConfig will be called when new service
+// configs are received by the resolver, and the result will be provided to the
+// Balancer in UpdateClientConnState.
 //
 // NOTE: this function must only be called during initialization time (i.e. in
 // an init() function), and is not thread-safe. If multiple Balancers are
@@ -46,8 +53,20 @@ func Register(b Builder) {
 	m[strings.ToLower(b.Name())] = b
 }
 
+// unregisterForTesting deletes the balancer with the given name from the
+// balancer map.
+//
+// This function is not thread-safe.
+func unregisterForTesting(name string) {
+	delete(m, name)
+}
+
+func init() {
+	internal.BalancerUnregister = unregisterForTesting
+}
+
 // Get returns the resolver builder registered with the given name.
-// Note that the compare is done in a case-insenstive fashion.
+// Note that the compare is done in a case-insensitive fashion.
 // If no builder is register with the name, nil will be returned.
 func Get(name string) Builder {
 	if b, ok := m[strings.ToLower(name)]; ok {
@@ -88,7 +107,15 @@ type SubConn interface {
 }
 
 // NewSubConnOptions contains options to create new SubConn.
-type NewSubConnOptions struct{}
+type NewSubConnOptions struct {
+	// CredsBundle is the credentials bundle that will be used in the created
+	// SubConn. If it's nil, the original creds from grpc DialOptions will be
+	// used.
+	CredsBundle credentials.Bundle
+	// HealthCheckEnabled indicates whether health check service should be
+	// enabled on this SubConn
+	HealthCheckEnabled bool
+}
 
 // ClientConn represents a gRPC ClientConn.
 //
@@ -105,7 +132,7 @@ type ClientConn interface {
 	// The SubConn will be shutdown.
 	RemoveSubConn(SubConn)
 
-	// UpdateBalancerState is called by balancer to nofity gRPC that some internal
+	// UpdateBalancerState is called by balancer to notify gRPC that some internal
 	// state in balancer has changed.
 	//
 	// gRPC will update the connectivity state of the ClientConn, and will call pick
@@ -116,6 +143,8 @@ type ClientConn interface {
 	ResolveNow(resolver.ResolveNowOption)
 
 	// Target returns the dial target for this ClientConn.
+	//
+	// Deprecated: Use the Target field in the BuildOptions instead.
 	Target() string
 }
 
@@ -125,12 +154,18 @@ type BuildOptions struct {
 	// use to dial to a remote load balancer server. The Balancer implementations
 	// can ignore this if it does not need to talk to another party securely.
 	DialCreds credentials.TransportCredentials
+	// CredsBundle is the credentials bundle that the Balancer can use.
+	CredsBundle credentials.Bundle
 	// Dialer is the custom dialer the Balancer implementation can use to dial
 	// to a remote load balancer server. The Balancer implementations
 	// can ignore this if it doesn't need to talk to remote balancer.
 	Dialer func(context.Context, string) (net.Conn, error)
 	// ChannelzParentID is the entity parent's channelz unique identification number.
 	ChannelzParentID int64
+	// Target contains the parsed address info of the dial target. It is the same resolver.Target as
+	// passed to the resolver.
+	// See the documentation for the resolver.Target type for details about what it contains.
+	Target resolver.Target
 }
 
 // Builder creates a balancer.
@@ -142,6 +177,14 @@ type Builder interface {
 	Name() string
 }
 
+// ConfigParser parses load balancer configs.
+type ConfigParser interface {
+	// ParseConfig parses the JSON load balancer config provided into an
+	// internal form or returns an error if the config is invalid.  For future
+	// compatibility reasons, unknown fields in the config should be ignored.
+	ParseConfig(LoadBalancingConfigJSON json.RawMessage) (serviceconfig.LoadBalancingConfig, error)
+}
+
 // PickOptions contains addition information for the Pick operation.
 type PickOptions struct {
 	// FullMethodName is the method name that NewClientStream() is called
@@ -153,10 +196,17 @@ type PickOptions struct {
 type DoneInfo struct {
 	// Err is the rpc error the RPC finished with. It could be nil.
 	Err error
+	// Trailer contains the metadata from the RPC's trailer, if present.
+	Trailer metadata.MD
 	// BytesSent indicates if any bytes have been sent to the server.
 	BytesSent bool
 	// BytesReceived indicates if any byte has been received from the server.
 	BytesReceived bool
+	// ServerLoad is the load received from server. It's usually sent as part of
+	// trailing metadata.
+	//
+	// The only supported type now is *orca_v1.LoadReport.
+	ServerLoad interface{}
 }
 
 var (
@@ -186,8 +236,10 @@ type Picker interface {
 	//
 	// If a SubConn is returned:
 	// - If it is READY, gRPC will send the RPC on it;
-	// - If it is not ready, or becomes not ready after it's returned, gRPC will block
-	//   until UpdateBalancerState() is called and will call pick on the new picker.
+	// - If it is not ready, or becomes not ready after it's returned, gRPC will
+	//   block until UpdateBalancerState() is called and will call pick on the
+	//   new picker. The done function returned from Pick(), if not nil, will be
+	//   called with nil error, no bytes sent and no bytes received.
 	//
 	// If the returned error is not nil:
 	// - If the error is ErrNoSubConnAvailable, gRPC will block until UpdateBalancerState()
@@ -198,9 +250,10 @@ type Picker interface {
 	// - Else (error is other non-nil error):
 	//   - The RPC will fail with unavailable error.
 	//
-	// The returned done() function will be called once the rpc has finished, with the
-	// final status of that RPC.
-	// done may be nil if balancer doesn't care about the RPC status.
+	// The returned done() function will be called once the rpc has finished,
+	// with the final status of that RPC.  If the SubConn returned is not a
+	// valid SubConn type, done may not be called.  done may be nil if balancer
+	// doesn't care about the RPC status.
 	Pick(ctx context.Context, opts PickOptions) (conn SubConn, done func(DoneInfo), err error)
 }
 
@@ -219,18 +272,55 @@ type Balancer interface {
 	// that back to gRPC.
 	// Balancer should also generate and update Pickers when its internal state has
 	// been changed by the new state.
+	//
+	// Deprecated: if V2Balancer is implemented by the Balancer,
+	// UpdateSubConnState will be called instead.
 	HandleSubConnStateChange(sc SubConn, state connectivity.State)
 	// HandleResolvedAddrs is called by gRPC to send updated resolved addresses to
 	// balancers.
 	// Balancer can create new SubConn or remove SubConn with the addresses.
 	// An empty address slice and a non-nil error will be passed if the resolver returns
 	// non-nil error to gRPC.
+	//
+	// Deprecated: if V2Balancer is implemented by the Balancer,
+	// UpdateClientConnState will be called instead.
 	HandleResolvedAddrs([]resolver.Address, error)
 	// Close closes the balancer. The balancer is not required to call
 	// ClientConn.RemoveSubConn for its existing SubConns.
 	Close()
 }
 
+// SubConnState describes the state of a SubConn.
+type SubConnState struct {
+	ConnectivityState connectivity.State
+	// TODO: add last connection error
+}
+
+// ClientConnState describes the state of a ClientConn relevant to the
+// balancer.
+type ClientConnState struct {
+	ResolverState resolver.State
+	// The parsed load balancing configuration returned by the builder's
+	// ParseConfig method, if implemented.
+	BalancerConfig serviceconfig.LoadBalancingConfig
+}
+
+// V2Balancer is defined for documentation purposes.  If a Balancer also
+// implements V2Balancer, its UpdateClientConnState method will be called
+// instead of HandleResolvedAddrs and its UpdateSubConnState will be called
+// instead of HandleSubConnStateChange.
+type V2Balancer interface {
+	// UpdateClientConnState is called by gRPC when the state of the ClientConn
+	// changes.
+	UpdateClientConnState(ClientConnState)
+	// UpdateSubConnState is called by gRPC when the state of a SubConn
+	// changes.
+	UpdateSubConnState(SubConn, SubConnState)
+	// Close closes the balancer. The balancer is not required to call
+	// ClientConn.RemoveSubConn for its existing SubConns.
+	Close()
+}
+
 // ConnectivityStateEvaluator takes the connectivity states of multiple SubConns
 // and returns one aggregated connectivity state.
 //
diff --git a/vendor/google.golang.org/grpc/balancer/base/balancer.go b/vendor/google.golang.org/grpc/balancer/base/balancer.go
index 23d13511..1af88f0a 100644
--- a/vendor/google.golang.org/grpc/balancer/base/balancer.go
+++ b/vendor/google.golang.org/grpc/balancer/base/balancer.go
@@ -19,7 +19,8 @@
 package base
 
 import (
-	"golang.org/x/net/context"
+	"context"
+
 	"google.golang.org/grpc/balancer"
 	"google.golang.org/grpc/connectivity"
 	"google.golang.org/grpc/grpclog"
@@ -29,6 +30,7 @@ import (
 type baseBuilder struct {
 	name          string
 	pickerBuilder PickerBuilder
+	config        Config
 }
 
 func (bb *baseBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer {
@@ -38,11 +40,12 @@ func (bb *baseBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions)
 
 		subConns: make(map[resolver.Address]balancer.SubConn),
 		scStates: make(map[balancer.SubConn]connectivity.State),
-		csEvltr:  &connectivityStateEvaluator{},
+		csEvltr:  &balancer.ConnectivityStateEvaluator{},
 		// Initialize picker to a picker that always return
 		// ErrNoSubConnAvailable, because when state of a SubConn changes, we
 		// may call UpdateBalancerState with this picker.
 		picker: NewErrPicker(balancer.ErrNoSubConnAvailable),
+		config: bb.config,
 	}
 }
 
@@ -54,27 +57,32 @@ type baseBalancer struct {
 	cc            balancer.ClientConn
 	pickerBuilder PickerBuilder
 
-	csEvltr *connectivityStateEvaluator
+	csEvltr *balancer.ConnectivityStateEvaluator
 	state   connectivity.State
 
 	subConns map[resolver.Address]balancer.SubConn
 	scStates map[balancer.SubConn]connectivity.State
 	picker   balancer.Picker
+	config   Config
 }
 
 func (b *baseBalancer) HandleResolvedAddrs(addrs []resolver.Address, err error) {
-	if err != nil {
-		grpclog.Infof("base.baseBalancer: HandleResolvedAddrs called with error %v", err)
-		return
+	panic("not implemented")
+}
+
+func (b *baseBalancer) UpdateClientConnState(s balancer.ClientConnState) {
+	// TODO: handle s.ResolverState.Err (log if not nil) once implemented.
+	// TODO: handle s.ResolverState.ServiceConfig?
+	if grpclog.V(2) {
+		grpclog.Infoln("base.baseBalancer: got new ClientConn state: ", s)
 	}
-	grpclog.Infoln("base.baseBalancer: got new resolved addresses: ", addrs)
 	// addrsSet is the set converted from addrs, it's used for quick lookup of an address.
 	addrsSet := make(map[resolver.Address]struct{})
-	for _, a := range addrs {
+	for _, a := range s.ResolverState.Addresses {
 		addrsSet[a] = struct{}{}
 		if _, ok := b.subConns[a]; !ok {
 			// a is a new address (not existing in b.subConns).
-			sc, err := b.cc.NewSubConn([]resolver.Address{a}, balancer.NewSubConnOptions{})
+			sc, err := b.cc.NewSubConn([]resolver.Address{a}, balancer.NewSubConnOptions{HealthCheckEnabled: b.config.HealthCheck})
 			if err != nil {
 				grpclog.Warningf("base.baseBalancer: failed to create new SubConn: %v", err)
 				continue
@@ -116,10 +124,19 @@ func (b *baseBalancer) regeneratePicker() {
 }
 
 func (b *baseBalancer) HandleSubConnStateChange(sc balancer.SubConn, s connectivity.State) {
-	grpclog.Infof("base.baseBalancer: handle SubConn state change: %p, %v", sc, s)
+	panic("not implemented")
+}
+
+func (b *baseBalancer) UpdateSubConnState(sc balancer.SubConn, state balancer.SubConnState) {
+	s := state.ConnectivityState
+	if grpclog.V(2) {
+		grpclog.Infof("base.baseBalancer: handle SubConn state change: %p, %v", sc, s)
+	}
 	oldS, ok := b.scStates[sc]
 	if !ok {
-		grpclog.Infof("base.baseBalancer: got state changes for an unknown SubConn: %p, %v", sc, s)
+		if grpclog.V(2) {
+			grpclog.Infof("base.baseBalancer: got state changes for an unknown SubConn: %p, %v", sc, s)
+		}
 		return
 	}
 	b.scStates[sc] = s
@@ -133,7 +150,7 @@ func (b *baseBalancer) HandleSubConnStateChange(sc balancer.SubConn, s connectiv
 	}
 
 	oldAggrState := b.state
-	b.state = b.csEvltr.recordTransition(oldS, s)
+	b.state = b.csEvltr.RecordTransition(oldS, s)
 
 	// Regenerate picker when one of the following happens:
 	//  - this sc became ready from not-ready
@@ -165,44 +182,3 @@ type errPicker struct {
 func (p *errPicker) Pick(ctx context.Context, opts balancer.PickOptions) (balancer.SubConn, func(balancer.DoneInfo), error) {
 	return nil, nil, p.err
 }
-
-// connectivityStateEvaluator gets updated by addrConns when their
-// states transition, based on which it evaluates the state of
-// ClientConn.
-type connectivityStateEvaluator struct {
-	numReady            uint64 // Number of addrConns in ready state.
-	numConnecting       uint64 // Number of addrConns in connecting state.
-	numTransientFailure uint64 // Number of addrConns in transientFailure.
-}
-
-// recordTransition records state change happening in every subConn and based on
-// that it evaluates what aggregated state should be.
-// It can only transition between Ready, Connecting and TransientFailure. Other states,
-// Idle and Shutdown are transitioned into by ClientConn; in the beginning of the connection
-// before any subConn is created ClientConn is in idle state. In the end when ClientConn
-// closes it is in Shutdown state.
-//
-// recordTransition should only be called synchronously from the same goroutine.
-func (cse *connectivityStateEvaluator) recordTransition(oldState, newState connectivity.State) connectivity.State {
-	// Update counters.
-	for idx, state := range []connectivity.State{oldState, newState} {
-		updateVal := 2*uint64(idx) - 1 // -1 for oldState and +1 for new.
-		switch state {
-		case connectivity.Ready:
-			cse.numReady += updateVal
-		case connectivity.Connecting:
-			cse.numConnecting += updateVal
-		case connectivity.TransientFailure:
-			cse.numTransientFailure += updateVal
-		}
-	}
-
-	// Evaluate.
-	if cse.numReady > 0 {
-		return connectivity.Ready
-	}
-	if cse.numConnecting > 0 {
-		return connectivity.Connecting
-	}
-	return connectivity.TransientFailure
-}
diff --git a/vendor/google.golang.org/grpc/balancer/base/base.go b/vendor/google.golang.org/grpc/balancer/base/base.go
index 012ace2f..34b1f299 100644
--- a/vendor/google.golang.org/grpc/balancer/base/base.go
+++ b/vendor/google.golang.org/grpc/balancer/base/base.go
@@ -45,8 +45,20 @@ type PickerBuilder interface {
 // NewBalancerBuilder returns a balancer builder. The balancers
 // built by this builder will use the picker builder to build pickers.
 func NewBalancerBuilder(name string, pb PickerBuilder) balancer.Builder {
+	return NewBalancerBuilderWithConfig(name, pb, Config{})
+}
+
+// Config contains the config info about the base balancer builder.
+type Config struct {
+	// HealthCheck indicates whether health checking should be enabled for this specific balancer.
+	HealthCheck bool
+}
+
+// NewBalancerBuilderWithConfig returns a base balancer builder configured by the provided config.
+func NewBalancerBuilderWithConfig(name string, pb PickerBuilder, config Config) balancer.Builder {
 	return &baseBuilder{
 		name:          name,
 		pickerBuilder: pb,
+		config:        config,
 	}
 }
diff --git a/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go b/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go
index 2eda0a1c..29f7a4dd 100644
--- a/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go
+++ b/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go
@@ -22,12 +22,13 @@
 package roundrobin
 
 import (
+	"context"
 	"sync"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/balancer"
 	"google.golang.org/grpc/balancer/base"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/grpcrand"
 	"google.golang.org/grpc/resolver"
 )
 
@@ -36,7 +37,7 @@ const Name = "round_robin"
 
 // newBuilder creates a new roundrobin balancer builder.
 func newBuilder() balancer.Builder {
-	return base.NewBalancerBuilder(Name, &rrPickerBuilder{})
+	return base.NewBalancerBuilderWithConfig(Name, &rrPickerBuilder{}, base.Config{HealthCheck: true})
 }
 
 func init() {
@@ -47,12 +48,19 @@ type rrPickerBuilder struct{}
 
 func (*rrPickerBuilder) Build(readySCs map[resolver.Address]balancer.SubConn) balancer.Picker {
 	grpclog.Infof("roundrobinPicker: newPicker called with readySCs: %v", readySCs)
+	if len(readySCs) == 0 {
+		return base.NewErrPicker(balancer.ErrNoSubConnAvailable)
+	}
 	var scs []balancer.SubConn
 	for _, sc := range readySCs {
 		scs = append(scs, sc)
 	}
 	return &rrPicker{
 		subConns: scs,
+		// Start at a random index, as the same RR balancer rebuilds a new
+		// picker when SubConn states change, and we don't want to apply excess
+		// load to the first server in the list.
+		next: grpcrand.Intn(len(scs)),
 	}
 }
 
@@ -67,10 +75,6 @@ type rrPicker struct {
 }
 
 func (p *rrPicker) Pick(ctx context.Context, opts balancer.PickOptions) (balancer.SubConn, func(balancer.DoneInfo), error) {
-	if len(p.subConns) <= 0 {
-		return nil, nil, balancer.ErrNoSubConnAvailable
-	}
-
 	p.mu.Lock()
 	sc := p.subConns[p.next]
 	p.next = (p.next + 1) % len(p.subConns)
diff --git a/vendor/google.golang.org/grpc/balancer_conn_wrappers.go b/vendor/google.golang.org/grpc/balancer_conn_wrappers.go
index c23f8170..8df4095c 100644
--- a/vendor/google.golang.org/grpc/balancer_conn_wrappers.go
+++ b/vendor/google.golang.org/grpc/balancer_conn_wrappers.go
@@ -82,20 +82,13 @@ func (b *scStateUpdateBuffer) get() <-chan *scStateUpdate {
 	return b.c
 }
 
-// resolverUpdate contains the new resolved addresses or error if there's
-// any.
-type resolverUpdate struct {
-	addrs []resolver.Address
-	err   error
-}
-
 // ccBalancerWrapper is a wrapper on top of cc for balancers.
 // It implements balancer.ClientConn interface.
 type ccBalancerWrapper struct {
 	cc               *ClientConn
 	balancer         balancer.Balancer
 	stateChangeQueue *scStateUpdateBuffer
-	resolverUpdateCh chan *resolverUpdate
+	ccUpdateCh       chan *balancer.ClientConnState
 	done             chan struct{}
 
 	mu       sync.Mutex
@@ -106,7 +99,7 @@ func newCCBalancerWrapper(cc *ClientConn, b balancer.Builder, bopts balancer.Bui
 	ccb := &ccBalancerWrapper{
 		cc:               cc,
 		stateChangeQueue: newSCStateUpdateBuffer(),
-		resolverUpdateCh: make(chan *resolverUpdate, 1),
+		ccUpdateCh:       make(chan *balancer.ClientConnState, 1),
 		done:             make(chan struct{}),
 		subConns:         make(map[*acBalancerWrapper]struct{}),
 	}
@@ -128,15 +121,23 @@ func (ccb *ccBalancerWrapper) watcher() {
 				return
 			default:
 			}
-			ccb.balancer.HandleSubConnStateChange(t.sc, t.state)
-		case t := <-ccb.resolverUpdateCh:
+			if ub, ok := ccb.balancer.(balancer.V2Balancer); ok {
+				ub.UpdateSubConnState(t.sc, balancer.SubConnState{ConnectivityState: t.state})
+			} else {
+				ccb.balancer.HandleSubConnStateChange(t.sc, t.state)
+			}
+		case s := <-ccb.ccUpdateCh:
 			select {
 			case <-ccb.done:
 				ccb.balancer.Close()
 				return
 			default:
 			}
-			ccb.balancer.HandleResolvedAddrs(t.addrs, t.err)
+			if ub, ok := ccb.balancer.(balancer.V2Balancer); ok {
+				ub.UpdateClientConnState(*s)
+			} else {
+				ccb.balancer.HandleResolvedAddrs(s.ResolverState.Addresses, nil)
+			}
 		case <-ccb.done:
 		}
 
@@ -150,9 +151,11 @@ func (ccb *ccBalancerWrapper) watcher() {
 			for acbw := range scs {
 				ccb.cc.removeAddrConn(acbw.getAddrConn(), errConnDrain)
 			}
+			ccb.UpdateBalancerState(connectivity.Connecting, nil)
 			return
 		default:
 		}
+		ccb.cc.firstResolveEvent.Fire()
 	}
 }
 
@@ -177,15 +180,24 @@ func (ccb *ccBalancerWrapper) handleSubConnStateChange(sc balancer.SubConn, s co
 	})
 }
 
-func (ccb *ccBalancerWrapper) handleResolvedAddrs(addrs []resolver.Address, err error) {
+func (ccb *ccBalancerWrapper) updateClientConnState(ccs *balancer.ClientConnState) {
+	if ccb.cc.curBalancerName != grpclbName {
+		// Filter any grpclb addresses since we don't have the grpclb balancer.
+		s := &ccs.ResolverState
+		for i := 0; i < len(s.Addresses); {
+			if s.Addresses[i].Type == resolver.GRPCLB {
+				copy(s.Addresses[i:], s.Addresses[i+1:])
+				s.Addresses = s.Addresses[:len(s.Addresses)-1]
+				continue
+			}
+			i++
+		}
+	}
 	select {
-	case <-ccb.resolverUpdateCh:
+	case <-ccb.ccUpdateCh:
 	default:
 	}
-	ccb.resolverUpdateCh <- &resolverUpdate{
-		addrs: addrs,
-		err:   err,
-	}
+	ccb.ccUpdateCh <- ccs
 }
 
 func (ccb *ccBalancerWrapper) NewSubConn(addrs []resolver.Address, opts balancer.NewSubConnOptions) (balancer.SubConn, error) {
@@ -197,7 +209,7 @@ func (ccb *ccBalancerWrapper) NewSubConn(addrs []resolver.Address, opts balancer
 	if ccb.subConns == nil {
 		return nil, fmt.Errorf("grpc: ClientConn balancer wrapper was closed")
 	}
-	ac, err := ccb.cc.newAddrConn(addrs)
+	ac, err := ccb.cc.newAddrConn(addrs, opts)
 	if err != nil {
 		return nil, err
 	}
@@ -229,8 +241,13 @@ func (ccb *ccBalancerWrapper) UpdateBalancerState(s connectivity.State, p balanc
 	if ccb.subConns == nil {
 		return
 	}
-	ccb.cc.csMgr.updateState(s)
+	// Update picker before updating state.  Even though the ordering here does
+	// not matter, it can lead to multiple calls of Pick in the common start-up
+	// case where we wait for ready and then perform an RPC.  If the picker is
+	// updated later, we could call the "connecting" picker when the state is
+	// updated, and then call the "ready" picker after the picker gets updated.
 	ccb.cc.blockingpicker.updatePicker(p)
+	ccb.cc.csMgr.updateState(s)
 }
 
 func (ccb *ccBalancerWrapper) ResolveNow(o resolver.ResolveNowOption) {
@@ -257,6 +274,7 @@ func (acbw *acBalancerWrapper) UpdateAddresses(addrs []resolver.Address) {
 	}
 	if !acbw.ac.tryUpdateAddrs(addrs) {
 		cc := acbw.ac.cc
+		opts := acbw.ac.scopts
 		acbw.ac.mu.Lock()
 		// Set old ac.acbw to nil so the Shutdown state update will be ignored
 		// by balancer.
@@ -272,7 +290,7 @@ func (acbw *acBalancerWrapper) UpdateAddresses(addrs []resolver.Address) {
 			return
 		}
 
-		ac, err := cc.newAddrConn(addrs)
+		ac, err := cc.newAddrConn(addrs, opts)
 		if err != nil {
 			grpclog.Warningf("acBalancerWrapper: UpdateAddresses: failed to newAddrConn: %v", err)
 			return
diff --git a/vendor/google.golang.org/grpc/balancer_v1_wrapper.go b/vendor/google.golang.org/grpc/balancer_v1_wrapper.go
index e0ce32cf..66e9a44a 100644
--- a/vendor/google.golang.org/grpc/balancer_v1_wrapper.go
+++ b/vendor/google.golang.org/grpc/balancer_v1_wrapper.go
@@ -19,16 +19,13 @@
 package grpc
 
 import (
-	"strings"
+	"context"
 	"sync"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/balancer"
-	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/connectivity"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/resolver"
-	"google.golang.org/grpc/status"
 )
 
 type balancerWrapperBuilder struct {
@@ -36,13 +33,7 @@ type balancerWrapperBuilder struct {
 }
 
 func (bwb *balancerWrapperBuilder) Build(cc balancer.ClientConn, opts balancer.BuildOptions) balancer.Balancer {
-	targetAddr := cc.Target()
-	targetSplitted := strings.Split(targetAddr, ":///")
-	if len(targetSplitted) >= 2 {
-		targetAddr = targetSplitted[1]
-	}
-
-	bwb.b.Start(targetAddr, BalancerConfig{
+	bwb.b.Start(opts.Target.Endpoint, BalancerConfig{
 		DialCreds: opts.DialCreds,
 		Dialer:    opts.Dialer,
 	})
@@ -51,7 +42,7 @@ func (bwb *balancerWrapperBuilder) Build(cc balancer.ClientConn, opts balancer.B
 		balancer:   bwb.b,
 		pickfirst:  pickfirst,
 		cc:         cc,
-		targetAddr: targetAddr,
+		targetAddr: opts.Target.Endpoint,
 		startCh:    make(chan struct{}),
 		conns:      make(map[resolver.Address]balancer.SubConn),
 		connSt:     make(map[balancer.SubConn]*scState),
@@ -122,7 +113,7 @@ func (bw *balancerWrapper) lbWatcher() {
 	}
 
 	for addrs := range notifyCh {
-		grpclog.Infof("balancerWrapper: got update addr from Notify: %v\n", addrs)
+		grpclog.Infof("balancerWrapper: got update addr from Notify: %v", addrs)
 		if bw.pickfirst {
 			var (
 				oldA  resolver.Address
@@ -283,9 +274,8 @@ func (bw *balancerWrapper) Close() {
 }
 
 // The picker is the balancerWrapper itself.
-// Pick should never return ErrNoSubConnAvailable.
 // It either blocks or returns error, consistent with v1 balancer Get().
-func (bw *balancerWrapper) Pick(ctx context.Context, opts balancer.PickOptions) (balancer.SubConn, func(balancer.DoneInfo), error) {
+func (bw *balancerWrapper) Pick(ctx context.Context, opts balancer.PickOptions) (sc balancer.SubConn, done func(balancer.DoneInfo), err error) {
 	failfast := true // Default failfast is true.
 	if ss, ok := rpcInfoFromContext(ctx); ok {
 		failfast = ss.failfast
@@ -294,35 +284,51 @@ func (bw *balancerWrapper) Pick(ctx context.Context, opts balancer.PickOptions)
 	if err != nil {
 		return nil, nil, err
 	}
-	var done func(balancer.DoneInfo)
 	if p != nil {
-		done = func(i balancer.DoneInfo) { p() }
+		done = func(balancer.DoneInfo) { p() }
+		defer func() {
+			if err != nil {
+				p()
+			}
+		}()
 	}
-	var sc balancer.SubConn
+
 	bw.mu.Lock()
 	defer bw.mu.Unlock()
 	if bw.pickfirst {
 		// Get the first sc in conns.
-		for _, sc = range bw.conns {
-			break
-		}
-	} else {
-		var ok bool
-		sc, ok = bw.conns[resolver.Address{
-			Addr:       a.Addr,
-			Type:       resolver.Backend,
-			ServerName: "",
-			Metadata:   a.Metadata,
-		}]
-		if !ok && failfast {
-			return nil, nil, status.Errorf(codes.Unavailable, "there is no connection available")
-		}
-		if s, ok := bw.connSt[sc]; failfast && (!ok || s.s != connectivity.Ready) {
-			// If the returned sc is not ready and RPC is failfast,
-			// return error, and this RPC will fail.
-			return nil, nil, status.Errorf(codes.Unavailable, "there is no connection available")
+		for _, sc := range bw.conns {
+			return sc, done, nil
 		}
+		return nil, nil, balancer.ErrNoSubConnAvailable
+	}
+	sc, ok1 := bw.conns[resolver.Address{
+		Addr:       a.Addr,
+		Type:       resolver.Backend,
+		ServerName: "",
+		Metadata:   a.Metadata,
+	}]
+	s, ok2 := bw.connSt[sc]
+	if !ok1 || !ok2 {
+		// This can only happen due to a race where Get() returned an address
+		// that was subsequently removed by Notify.  In this case we should
+		// retry always.
+		return nil, nil, balancer.ErrNoSubConnAvailable
+	}
+	switch s.s {
+	case connectivity.Ready, connectivity.Idle:
+		return sc, done, nil
+	case connectivity.Shutdown, connectivity.TransientFailure:
+		// If the returned sc has been shut down or is in transient failure,
+		// return error, and this RPC will fail or wait for another picker (if
+		// non-failfast).
+		return nil, nil, balancer.ErrTransientFailure
+	default:
+		// For other states (connecting or unknown), the v1 balancer would
+		// traditionally wait until ready and then issue the RPC.  Returning
+		// ErrNoSubConnAvailable will be a slight improvement in that it will
+		// allow the balancer to choose another address in case others are
+		// connected.
+		return nil, nil, balancer.ErrNoSubConnAvailable
 	}
-
-	return sc, done, nil
 }
diff --git a/vendor/google.golang.org/grpc/binarylog/grpc_binarylog_v1/binarylog.pb.go b/vendor/google.golang.org/grpc/binarylog/grpc_binarylog_v1/binarylog.pb.go
new file mode 100644
index 00000000..f393bb66
--- /dev/null
+++ b/vendor/google.golang.org/grpc/binarylog/grpc_binarylog_v1/binarylog.pb.go
@@ -0,0 +1,900 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: grpc/binarylog/grpc_binarylog_v1/binarylog.proto
+
+package grpc_binarylog_v1 // import "google.golang.org/grpc/binarylog/grpc_binarylog_v1"
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+import duration "github.com/golang/protobuf/ptypes/duration"
+import timestamp "github.com/golang/protobuf/ptypes/timestamp"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+// Enumerates the type of event
+// Note the terminology is different from the RPC semantics
+// definition, but the same meaning is expressed here.
+type GrpcLogEntry_EventType int32
+
+const (
+	GrpcLogEntry_EVENT_TYPE_UNKNOWN GrpcLogEntry_EventType = 0
+	// Header sent from client to server
+	GrpcLogEntry_EVENT_TYPE_CLIENT_HEADER GrpcLogEntry_EventType = 1
+	// Header sent from server to client
+	GrpcLogEntry_EVENT_TYPE_SERVER_HEADER GrpcLogEntry_EventType = 2
+	// Message sent from client to server
+	GrpcLogEntry_EVENT_TYPE_CLIENT_MESSAGE GrpcLogEntry_EventType = 3
+	// Message sent from server to client
+	GrpcLogEntry_EVENT_TYPE_SERVER_MESSAGE GrpcLogEntry_EventType = 4
+	// A signal that client is done sending
+	GrpcLogEntry_EVENT_TYPE_CLIENT_HALF_CLOSE GrpcLogEntry_EventType = 5
+	// Trailer indicates the end of the RPC.
+	// On client side, this event means a trailer was either received
+	// from the network or the gRPC library locally generated a status
+	// to inform the application about a failure.
+	// On server side, this event means the server application requested
+	// to send a trailer. Note: EVENT_TYPE_CANCEL may still arrive after
+	// this due to races on server side.
+	GrpcLogEntry_EVENT_TYPE_SERVER_TRAILER GrpcLogEntry_EventType = 6
+	// A signal that the RPC is cancelled. On client side, this
+	// indicates the client application requests a cancellation.
+	// On server side, this indicates that cancellation was detected.
+	// Note: This marks the end of the RPC. Events may arrive after
+	// this due to races. For example, on client side a trailer
+	// may arrive even though the application requested to cancel the RPC.
+	GrpcLogEntry_EVENT_TYPE_CANCEL GrpcLogEntry_EventType = 7
+)
+
+var GrpcLogEntry_EventType_name = map[int32]string{
+	0: "EVENT_TYPE_UNKNOWN",
+	1: "EVENT_TYPE_CLIENT_HEADER",
+	2: "EVENT_TYPE_SERVER_HEADER",
+	3: "EVENT_TYPE_CLIENT_MESSAGE",
+	4: "EVENT_TYPE_SERVER_MESSAGE",
+	5: "EVENT_TYPE_CLIENT_HALF_CLOSE",
+	6: "EVENT_TYPE_SERVER_TRAILER",
+	7: "EVENT_TYPE_CANCEL",
+}
+var GrpcLogEntry_EventType_value = map[string]int32{
+	"EVENT_TYPE_UNKNOWN":           0,
+	"EVENT_TYPE_CLIENT_HEADER":     1,
+	"EVENT_TYPE_SERVER_HEADER":     2,
+	"EVENT_TYPE_CLIENT_MESSAGE":    3,
+	"EVENT_TYPE_SERVER_MESSAGE":    4,
+	"EVENT_TYPE_CLIENT_HALF_CLOSE": 5,
+	"EVENT_TYPE_SERVER_TRAILER":    6,
+	"EVENT_TYPE_CANCEL":            7,
+}
+
+func (x GrpcLogEntry_EventType) String() string {
+	return proto.EnumName(GrpcLogEntry_EventType_name, int32(x))
+}
+func (GrpcLogEntry_EventType) EnumDescriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{0, 0}
+}
+
+// Enumerates the entity that generates the log entry
+type GrpcLogEntry_Logger int32
+
+const (
+	GrpcLogEntry_LOGGER_UNKNOWN GrpcLogEntry_Logger = 0
+	GrpcLogEntry_LOGGER_CLIENT  GrpcLogEntry_Logger = 1
+	GrpcLogEntry_LOGGER_SERVER  GrpcLogEntry_Logger = 2
+)
+
+var GrpcLogEntry_Logger_name = map[int32]string{
+	0: "LOGGER_UNKNOWN",
+	1: "LOGGER_CLIENT",
+	2: "LOGGER_SERVER",
+}
+var GrpcLogEntry_Logger_value = map[string]int32{
+	"LOGGER_UNKNOWN": 0,
+	"LOGGER_CLIENT":  1,
+	"LOGGER_SERVER":  2,
+}
+
+func (x GrpcLogEntry_Logger) String() string {
+	return proto.EnumName(GrpcLogEntry_Logger_name, int32(x))
+}
+func (GrpcLogEntry_Logger) EnumDescriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{0, 1}
+}
+
+type Address_Type int32
+
+const (
+	Address_TYPE_UNKNOWN Address_Type = 0
+	// address is in 1.2.3.4 form
+	Address_TYPE_IPV4 Address_Type = 1
+	// address is in IPv6 canonical form (RFC5952 section 4)
+	// The scope is NOT included in the address string.
+	Address_TYPE_IPV6 Address_Type = 2
+	// address is UDS string
+	Address_TYPE_UNIX Address_Type = 3
+)
+
+var Address_Type_name = map[int32]string{
+	0: "TYPE_UNKNOWN",
+	1: "TYPE_IPV4",
+	2: "TYPE_IPV6",
+	3: "TYPE_UNIX",
+}
+var Address_Type_value = map[string]int32{
+	"TYPE_UNKNOWN": 0,
+	"TYPE_IPV4":    1,
+	"TYPE_IPV6":    2,
+	"TYPE_UNIX":    3,
+}
+
+func (x Address_Type) String() string {
+	return proto.EnumName(Address_Type_name, int32(x))
+}
+func (Address_Type) EnumDescriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{7, 0}
+}
+
+// Log entry we store in binary logs
+type GrpcLogEntry struct {
+	// The timestamp of the binary log message
+	Timestamp *timestamp.Timestamp `protobuf:"bytes,1,opt,name=timestamp,proto3" json:"timestamp,omitempty"`
+	// Uniquely identifies a call. The value must not be 0 in order to disambiguate
+	// from an unset value.
+	// Each call may have several log entries, they will all have the same call_id.
+	// Nothing is guaranteed about their value other than they are unique across
+	// different RPCs in the same gRPC process.
+	CallId uint64 `protobuf:"varint,2,opt,name=call_id,json=callId,proto3" json:"call_id,omitempty"`
+	// The entry sequence id for this call. The first GrpcLogEntry has a
+	// value of 1, to disambiguate from an unset value. The purpose of
+	// this field is to detect missing entries in environments where
+	// durability or ordering is not guaranteed.
+	SequenceIdWithinCall uint64                 `protobuf:"varint,3,opt,name=sequence_id_within_call,json=sequenceIdWithinCall,proto3" json:"sequence_id_within_call,omitempty"`
+	Type                 GrpcLogEntry_EventType `protobuf:"varint,4,opt,name=type,proto3,enum=grpc.binarylog.v1.GrpcLogEntry_EventType" json:"type,omitempty"`
+	Logger               GrpcLogEntry_Logger    `protobuf:"varint,5,opt,name=logger,proto3,enum=grpc.binarylog.v1.GrpcLogEntry_Logger" json:"logger,omitempty"`
+	// The logger uses one of the following fields to record the payload,
+	// according to the type of the log entry.
+	//
+	// Types that are valid to be assigned to Payload:
+	//	*GrpcLogEntry_ClientHeader
+	//	*GrpcLogEntry_ServerHeader
+	//	*GrpcLogEntry_Message
+	//	*GrpcLogEntry_Trailer
+	Payload isGrpcLogEntry_Payload `protobuf_oneof:"payload"`
+	// true if payload does not represent the full message or metadata.
+	PayloadTruncated bool `protobuf:"varint,10,opt,name=payload_truncated,json=payloadTruncated,proto3" json:"payload_truncated,omitempty"`
+	// Peer address information, will only be recorded on the first
+	// incoming event. On client side, peer is logged on
+	// EVENT_TYPE_SERVER_HEADER normally or EVENT_TYPE_SERVER_TRAILER in
+	// the case of trailers-only. On server side, peer is always
+	// logged on EVENT_TYPE_CLIENT_HEADER.
+	Peer                 *Address `protobuf:"bytes,11,opt,name=peer,proto3" json:"peer,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *GrpcLogEntry) Reset()         { *m = GrpcLogEntry{} }
+func (m *GrpcLogEntry) String() string { return proto.CompactTextString(m) }
+func (*GrpcLogEntry) ProtoMessage()    {}
+func (*GrpcLogEntry) Descriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{0}
+}
+func (m *GrpcLogEntry) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_GrpcLogEntry.Unmarshal(m, b)
+}
+func (m *GrpcLogEntry) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_GrpcLogEntry.Marshal(b, m, deterministic)
+}
+func (dst *GrpcLogEntry) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_GrpcLogEntry.Merge(dst, src)
+}
+func (m *GrpcLogEntry) XXX_Size() int {
+	return xxx_messageInfo_GrpcLogEntry.Size(m)
+}
+func (m *GrpcLogEntry) XXX_DiscardUnknown() {
+	xxx_messageInfo_GrpcLogEntry.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_GrpcLogEntry proto.InternalMessageInfo
+
+func (m *GrpcLogEntry) GetTimestamp() *timestamp.Timestamp {
+	if m != nil {
+		return m.Timestamp
+	}
+	return nil
+}
+
+func (m *GrpcLogEntry) GetCallId() uint64 {
+	if m != nil {
+		return m.CallId
+	}
+	return 0
+}
+
+func (m *GrpcLogEntry) GetSequenceIdWithinCall() uint64 {
+	if m != nil {
+		return m.SequenceIdWithinCall
+	}
+	return 0
+}
+
+func (m *GrpcLogEntry) GetType() GrpcLogEntry_EventType {
+	if m != nil {
+		return m.Type
+	}
+	return GrpcLogEntry_EVENT_TYPE_UNKNOWN
+}
+
+func (m *GrpcLogEntry) GetLogger() GrpcLogEntry_Logger {
+	if m != nil {
+		return m.Logger
+	}
+	return GrpcLogEntry_LOGGER_UNKNOWN
+}
+
+type isGrpcLogEntry_Payload interface {
+	isGrpcLogEntry_Payload()
+}
+
+type GrpcLogEntry_ClientHeader struct {
+	ClientHeader *ClientHeader `protobuf:"bytes,6,opt,name=client_header,json=clientHeader,proto3,oneof"`
+}
+
+type GrpcLogEntry_ServerHeader struct {
+	ServerHeader *ServerHeader `protobuf:"bytes,7,opt,name=server_header,json=serverHeader,proto3,oneof"`
+}
+
+type GrpcLogEntry_Message struct {
+	Message *Message `protobuf:"bytes,8,opt,name=message,proto3,oneof"`
+}
+
+type GrpcLogEntry_Trailer struct {
+	Trailer *Trailer `protobuf:"bytes,9,opt,name=trailer,proto3,oneof"`
+}
+
+func (*GrpcLogEntry_ClientHeader) isGrpcLogEntry_Payload() {}
+
+func (*GrpcLogEntry_ServerHeader) isGrpcLogEntry_Payload() {}
+
+func (*GrpcLogEntry_Message) isGrpcLogEntry_Payload() {}
+
+func (*GrpcLogEntry_Trailer) isGrpcLogEntry_Payload() {}
+
+func (m *GrpcLogEntry) GetPayload() isGrpcLogEntry_Payload {
+	if m != nil {
+		return m.Payload
+	}
+	return nil
+}
+
+func (m *GrpcLogEntry) GetClientHeader() *ClientHeader {
+	if x, ok := m.GetPayload().(*GrpcLogEntry_ClientHeader); ok {
+		return x.ClientHeader
+	}
+	return nil
+}
+
+func (m *GrpcLogEntry) GetServerHeader() *ServerHeader {
+	if x, ok := m.GetPayload().(*GrpcLogEntry_ServerHeader); ok {
+		return x.ServerHeader
+	}
+	return nil
+}
+
+func (m *GrpcLogEntry) GetMessage() *Message {
+	if x, ok := m.GetPayload().(*GrpcLogEntry_Message); ok {
+		return x.Message
+	}
+	return nil
+}
+
+func (m *GrpcLogEntry) GetTrailer() *Trailer {
+	if x, ok := m.GetPayload().(*GrpcLogEntry_Trailer); ok {
+		return x.Trailer
+	}
+	return nil
+}
+
+func (m *GrpcLogEntry) GetPayloadTruncated() bool {
+	if m != nil {
+		return m.PayloadTruncated
+	}
+	return false
+}
+
+func (m *GrpcLogEntry) GetPeer() *Address {
+	if m != nil {
+		return m.Peer
+	}
+	return nil
+}
+
+// XXX_OneofFuncs is for the internal use of the proto package.
+func (*GrpcLogEntry) XXX_OneofFuncs() (func(msg proto.Message, b *proto.Buffer) error, func(msg proto.Message, tag, wire int, b *proto.Buffer) (bool, error), func(msg proto.Message) (n int), []interface{}) {
+	return _GrpcLogEntry_OneofMarshaler, _GrpcLogEntry_OneofUnmarshaler, _GrpcLogEntry_OneofSizer, []interface{}{
+		(*GrpcLogEntry_ClientHeader)(nil),
+		(*GrpcLogEntry_ServerHeader)(nil),
+		(*GrpcLogEntry_Message)(nil),
+		(*GrpcLogEntry_Trailer)(nil),
+	}
+}
+
+func _GrpcLogEntry_OneofMarshaler(msg proto.Message, b *proto.Buffer) error {
+	m := msg.(*GrpcLogEntry)
+	// payload
+	switch x := m.Payload.(type) {
+	case *GrpcLogEntry_ClientHeader:
+		b.EncodeVarint(6<<3 | proto.WireBytes)
+		if err := b.EncodeMessage(x.ClientHeader); err != nil {
+			return err
+		}
+	case *GrpcLogEntry_ServerHeader:
+		b.EncodeVarint(7<<3 | proto.WireBytes)
+		if err := b.EncodeMessage(x.ServerHeader); err != nil {
+			return err
+		}
+	case *GrpcLogEntry_Message:
+		b.EncodeVarint(8<<3 | proto.WireBytes)
+		if err := b.EncodeMessage(x.Message); err != nil {
+			return err
+		}
+	case *GrpcLogEntry_Trailer:
+		b.EncodeVarint(9<<3 | proto.WireBytes)
+		if err := b.EncodeMessage(x.Trailer); err != nil {
+			return err
+		}
+	case nil:
+	default:
+		return fmt.Errorf("GrpcLogEntry.Payload has unexpected type %T", x)
+	}
+	return nil
+}
+
+func _GrpcLogEntry_OneofUnmarshaler(msg proto.Message, tag, wire int, b *proto.Buffer) (bool, error) {
+	m := msg.(*GrpcLogEntry)
+	switch tag {
+	case 6: // payload.client_header
+		if wire != proto.WireBytes {
+			return true, proto.ErrInternalBadWireType
+		}
+		msg := new(ClientHeader)
+		err := b.DecodeMessage(msg)
+		m.Payload = &GrpcLogEntry_ClientHeader{msg}
+		return true, err
+	case 7: // payload.server_header
+		if wire != proto.WireBytes {
+			return true, proto.ErrInternalBadWireType
+		}
+		msg := new(ServerHeader)
+		err := b.DecodeMessage(msg)
+		m.Payload = &GrpcLogEntry_ServerHeader{msg}
+		return true, err
+	case 8: // payload.message
+		if wire != proto.WireBytes {
+			return true, proto.ErrInternalBadWireType
+		}
+		msg := new(Message)
+		err := b.DecodeMessage(msg)
+		m.Payload = &GrpcLogEntry_Message{msg}
+		return true, err
+	case 9: // payload.trailer
+		if wire != proto.WireBytes {
+			return true, proto.ErrInternalBadWireType
+		}
+		msg := new(Trailer)
+		err := b.DecodeMessage(msg)
+		m.Payload = &GrpcLogEntry_Trailer{msg}
+		return true, err
+	default:
+		return false, nil
+	}
+}
+
+func _GrpcLogEntry_OneofSizer(msg proto.Message) (n int) {
+	m := msg.(*GrpcLogEntry)
+	// payload
+	switch x := m.Payload.(type) {
+	case *GrpcLogEntry_ClientHeader:
+		s := proto.Size(x.ClientHeader)
+		n += 1 // tag and wire
+		n += proto.SizeVarint(uint64(s))
+		n += s
+	case *GrpcLogEntry_ServerHeader:
+		s := proto.Size(x.ServerHeader)
+		n += 1 // tag and wire
+		n += proto.SizeVarint(uint64(s))
+		n += s
+	case *GrpcLogEntry_Message:
+		s := proto.Size(x.Message)
+		n += 1 // tag and wire
+		n += proto.SizeVarint(uint64(s))
+		n += s
+	case *GrpcLogEntry_Trailer:
+		s := proto.Size(x.Trailer)
+		n += 1 // tag and wire
+		n += proto.SizeVarint(uint64(s))
+		n += s
+	case nil:
+	default:
+		panic(fmt.Sprintf("proto: unexpected type %T in oneof", x))
+	}
+	return n
+}
+
+type ClientHeader struct {
+	// This contains only the metadata from the application.
+	Metadata *Metadata `protobuf:"bytes,1,opt,name=metadata,proto3" json:"metadata,omitempty"`
+	// The name of the RPC method, which looks something like:
+	// /<service>/<method>
+	// Note the leading "/" character.
+	MethodName string `protobuf:"bytes,2,opt,name=method_name,json=methodName,proto3" json:"method_name,omitempty"`
+	// A single process may be used to run multiple virtual
+	// servers with different identities.
+	// The authority is the name of such a server identitiy.
+	// It is typically a portion of the URI in the form of
+	// <host> or <host>:<port> .
+	Authority string `protobuf:"bytes,3,opt,name=authority,proto3" json:"authority,omitempty"`
+	// the RPC timeout
+	Timeout              *duration.Duration `protobuf:"bytes,4,opt,name=timeout,proto3" json:"timeout,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}           `json:"-"`
+	XXX_unrecognized     []byte             `json:"-"`
+	XXX_sizecache        int32              `json:"-"`
+}
+
+func (m *ClientHeader) Reset()         { *m = ClientHeader{} }
+func (m *ClientHeader) String() string { return proto.CompactTextString(m) }
+func (*ClientHeader) ProtoMessage()    {}
+func (*ClientHeader) Descriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{1}
+}
+func (m *ClientHeader) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_ClientHeader.Unmarshal(m, b)
+}
+func (m *ClientHeader) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_ClientHeader.Marshal(b, m, deterministic)
+}
+func (dst *ClientHeader) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_ClientHeader.Merge(dst, src)
+}
+func (m *ClientHeader) XXX_Size() int {
+	return xxx_messageInfo_ClientHeader.Size(m)
+}
+func (m *ClientHeader) XXX_DiscardUnknown() {
+	xxx_messageInfo_ClientHeader.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_ClientHeader proto.InternalMessageInfo
+
+func (m *ClientHeader) GetMetadata() *Metadata {
+	if m != nil {
+		return m.Metadata
+	}
+	return nil
+}
+
+func (m *ClientHeader) GetMethodName() string {
+	if m != nil {
+		return m.MethodName
+	}
+	return ""
+}
+
+func (m *ClientHeader) GetAuthority() string {
+	if m != nil {
+		return m.Authority
+	}
+	return ""
+}
+
+func (m *ClientHeader) GetTimeout() *duration.Duration {
+	if m != nil {
+		return m.Timeout
+	}
+	return nil
+}
+
+type ServerHeader struct {
+	// This contains only the metadata from the application.
+	Metadata             *Metadata `protobuf:"bytes,1,opt,name=metadata,proto3" json:"metadata,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}  `json:"-"`
+	XXX_unrecognized     []byte    `json:"-"`
+	XXX_sizecache        int32     `json:"-"`
+}
+
+func (m *ServerHeader) Reset()         { *m = ServerHeader{} }
+func (m *ServerHeader) String() string { return proto.CompactTextString(m) }
+func (*ServerHeader) ProtoMessage()    {}
+func (*ServerHeader) Descriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{2}
+}
+func (m *ServerHeader) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_ServerHeader.Unmarshal(m, b)
+}
+func (m *ServerHeader) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_ServerHeader.Marshal(b, m, deterministic)
+}
+func (dst *ServerHeader) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_ServerHeader.Merge(dst, src)
+}
+func (m *ServerHeader) XXX_Size() int {
+	return xxx_messageInfo_ServerHeader.Size(m)
+}
+func (m *ServerHeader) XXX_DiscardUnknown() {
+	xxx_messageInfo_ServerHeader.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_ServerHeader proto.InternalMessageInfo
+
+func (m *ServerHeader) GetMetadata() *Metadata {
+	if m != nil {
+		return m.Metadata
+	}
+	return nil
+}
+
+type Trailer struct {
+	// This contains only the metadata from the application.
+	Metadata *Metadata `protobuf:"bytes,1,opt,name=metadata,proto3" json:"metadata,omitempty"`
+	// The gRPC status code.
+	StatusCode uint32 `protobuf:"varint,2,opt,name=status_code,json=statusCode,proto3" json:"status_code,omitempty"`
+	// An original status message before any transport specific
+	// encoding.
+	StatusMessage string `protobuf:"bytes,3,opt,name=status_message,json=statusMessage,proto3" json:"status_message,omitempty"`
+	// The value of the 'grpc-status-details-bin' metadata key. If
+	// present, this is always an encoded 'google.rpc.Status' message.
+	StatusDetails        []byte   `protobuf:"bytes,4,opt,name=status_details,json=statusDetails,proto3" json:"status_details,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Trailer) Reset()         { *m = Trailer{} }
+func (m *Trailer) String() string { return proto.CompactTextString(m) }
+func (*Trailer) ProtoMessage()    {}
+func (*Trailer) Descriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{3}
+}
+func (m *Trailer) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Trailer.Unmarshal(m, b)
+}
+func (m *Trailer) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Trailer.Marshal(b, m, deterministic)
+}
+func (dst *Trailer) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Trailer.Merge(dst, src)
+}
+func (m *Trailer) XXX_Size() int {
+	return xxx_messageInfo_Trailer.Size(m)
+}
+func (m *Trailer) XXX_DiscardUnknown() {
+	xxx_messageInfo_Trailer.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Trailer proto.InternalMessageInfo
+
+func (m *Trailer) GetMetadata() *Metadata {
+	if m != nil {
+		return m.Metadata
+	}
+	return nil
+}
+
+func (m *Trailer) GetStatusCode() uint32 {
+	if m != nil {
+		return m.StatusCode
+	}
+	return 0
+}
+
+func (m *Trailer) GetStatusMessage() string {
+	if m != nil {
+		return m.StatusMessage
+	}
+	return ""
+}
+
+func (m *Trailer) GetStatusDetails() []byte {
+	if m != nil {
+		return m.StatusDetails
+	}
+	return nil
+}
+
+// Message payload, used by CLIENT_MESSAGE and SERVER_MESSAGE
+type Message struct {
+	// Length of the message. It may not be the same as the length of the
+	// data field, as the logging payload can be truncated or omitted.
+	Length uint32 `protobuf:"varint,1,opt,name=length,proto3" json:"length,omitempty"`
+	// May be truncated or omitted.
+	Data                 []byte   `protobuf:"bytes,2,opt,name=data,proto3" json:"data,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Message) Reset()         { *m = Message{} }
+func (m *Message) String() string { return proto.CompactTextString(m) }
+func (*Message) ProtoMessage()    {}
+func (*Message) Descriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{4}
+}
+func (m *Message) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Message.Unmarshal(m, b)
+}
+func (m *Message) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Message.Marshal(b, m, deterministic)
+}
+func (dst *Message) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Message.Merge(dst, src)
+}
+func (m *Message) XXX_Size() int {
+	return xxx_messageInfo_Message.Size(m)
+}
+func (m *Message) XXX_DiscardUnknown() {
+	xxx_messageInfo_Message.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Message proto.InternalMessageInfo
+
+func (m *Message) GetLength() uint32 {
+	if m != nil {
+		return m.Length
+	}
+	return 0
+}
+
+func (m *Message) GetData() []byte {
+	if m != nil {
+		return m.Data
+	}
+	return nil
+}
+
+// A list of metadata pairs, used in the payload of client header,
+// server header, and server trailer.
+// Implementations may omit some entries to honor the header limits
+// of GRPC_BINARY_LOG_CONFIG.
+//
+// Header keys added by gRPC are omitted. To be more specific,
+// implementations will not log the following entries, and this is
+// not to be treated as a truncation:
+// - entries handled by grpc that are not user visible, such as those
+//   that begin with 'grpc-' (with exception of grpc-trace-bin)
+//   or keys like 'lb-token'
+// - transport specific entries, including but not limited to:
+//   ':path', ':authority', 'content-encoding', 'user-agent', 'te', etc
+// - entries added for call credentials
+//
+// Implementations must always log grpc-trace-bin if it is present.
+// Practically speaking it will only be visible on server side because
+// grpc-trace-bin is managed by low level client side mechanisms
+// inaccessible from the application level. On server side, the
+// header is just a normal metadata key.
+// The pair will not count towards the size limit.
+type Metadata struct {
+	Entry                []*MetadataEntry `protobuf:"bytes,1,rep,name=entry,proto3" json:"entry,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}         `json:"-"`
+	XXX_unrecognized     []byte           `json:"-"`
+	XXX_sizecache        int32            `json:"-"`
+}
+
+func (m *Metadata) Reset()         { *m = Metadata{} }
+func (m *Metadata) String() string { return proto.CompactTextString(m) }
+func (*Metadata) ProtoMessage()    {}
+func (*Metadata) Descriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{5}
+}
+func (m *Metadata) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Metadata.Unmarshal(m, b)
+}
+func (m *Metadata) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Metadata.Marshal(b, m, deterministic)
+}
+func (dst *Metadata) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Metadata.Merge(dst, src)
+}
+func (m *Metadata) XXX_Size() int {
+	return xxx_messageInfo_Metadata.Size(m)
+}
+func (m *Metadata) XXX_DiscardUnknown() {
+	xxx_messageInfo_Metadata.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Metadata proto.InternalMessageInfo
+
+func (m *Metadata) GetEntry() []*MetadataEntry {
+	if m != nil {
+		return m.Entry
+	}
+	return nil
+}
+
+// A metadata key value pair
+type MetadataEntry struct {
+	Key                  string   `protobuf:"bytes,1,opt,name=key,proto3" json:"key,omitempty"`
+	Value                []byte   `protobuf:"bytes,2,opt,name=value,proto3" json:"value,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *MetadataEntry) Reset()         { *m = MetadataEntry{} }
+func (m *MetadataEntry) String() string { return proto.CompactTextString(m) }
+func (*MetadataEntry) ProtoMessage()    {}
+func (*MetadataEntry) Descriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{6}
+}
+func (m *MetadataEntry) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_MetadataEntry.Unmarshal(m, b)
+}
+func (m *MetadataEntry) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_MetadataEntry.Marshal(b, m, deterministic)
+}
+func (dst *MetadataEntry) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_MetadataEntry.Merge(dst, src)
+}
+func (m *MetadataEntry) XXX_Size() int {
+	return xxx_messageInfo_MetadataEntry.Size(m)
+}
+func (m *MetadataEntry) XXX_DiscardUnknown() {
+	xxx_messageInfo_MetadataEntry.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_MetadataEntry proto.InternalMessageInfo
+
+func (m *MetadataEntry) GetKey() string {
+	if m != nil {
+		return m.Key
+	}
+	return ""
+}
+
+func (m *MetadataEntry) GetValue() []byte {
+	if m != nil {
+		return m.Value
+	}
+	return nil
+}
+
+// Address information
+type Address struct {
+	Type    Address_Type `protobuf:"varint,1,opt,name=type,proto3,enum=grpc.binarylog.v1.Address_Type" json:"type,omitempty"`
+	Address string       `protobuf:"bytes,2,opt,name=address,proto3" json:"address,omitempty"`
+	// only for TYPE_IPV4 and TYPE_IPV6
+	IpPort               uint32   `protobuf:"varint,3,opt,name=ip_port,json=ipPort,proto3" json:"ip_port,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Address) Reset()         { *m = Address{} }
+func (m *Address) String() string { return proto.CompactTextString(m) }
+func (*Address) ProtoMessage()    {}
+func (*Address) Descriptor() ([]byte, []int) {
+	return fileDescriptor_binarylog_264c8c9c551ce911, []int{7}
+}
+func (m *Address) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Address.Unmarshal(m, b)
+}
+func (m *Address) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Address.Marshal(b, m, deterministic)
+}
+func (dst *Address) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Address.Merge(dst, src)
+}
+func (m *Address) XXX_Size() int {
+	return xxx_messageInfo_Address.Size(m)
+}
+func (m *Address) XXX_DiscardUnknown() {
+	xxx_messageInfo_Address.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Address proto.InternalMessageInfo
+
+func (m *Address) GetType() Address_Type {
+	if m != nil {
+		return m.Type
+	}
+	return Address_TYPE_UNKNOWN
+}
+
+func (m *Address) GetAddress() string {
+	if m != nil {
+		return m.Address
+	}
+	return ""
+}
+
+func (m *Address) GetIpPort() uint32 {
+	if m != nil {
+		return m.IpPort
+	}
+	return 0
+}
+
+func init() {
+	proto.RegisterType((*GrpcLogEntry)(nil), "grpc.binarylog.v1.GrpcLogEntry")
+	proto.RegisterType((*ClientHeader)(nil), "grpc.binarylog.v1.ClientHeader")
+	proto.RegisterType((*ServerHeader)(nil), "grpc.binarylog.v1.ServerHeader")
+	proto.RegisterType((*Trailer)(nil), "grpc.binarylog.v1.Trailer")
+	proto.RegisterType((*Message)(nil), "grpc.binarylog.v1.Message")
+	proto.RegisterType((*Metadata)(nil), "grpc.binarylog.v1.Metadata")
+	proto.RegisterType((*MetadataEntry)(nil), "grpc.binarylog.v1.MetadataEntry")
+	proto.RegisterType((*Address)(nil), "grpc.binarylog.v1.Address")
+	proto.RegisterEnum("grpc.binarylog.v1.GrpcLogEntry_EventType", GrpcLogEntry_EventType_name, GrpcLogEntry_EventType_value)
+	proto.RegisterEnum("grpc.binarylog.v1.GrpcLogEntry_Logger", GrpcLogEntry_Logger_name, GrpcLogEntry_Logger_value)
+	proto.RegisterEnum("grpc.binarylog.v1.Address_Type", Address_Type_name, Address_Type_value)
+}
+
+func init() {
+	proto.RegisterFile("grpc/binarylog/grpc_binarylog_v1/binarylog.proto", fileDescriptor_binarylog_264c8c9c551ce911)
+}
+
+var fileDescriptor_binarylog_264c8c9c551ce911 = []byte{
+	// 900 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x55, 0x51, 0x6f, 0xe3, 0x44,
+	0x10, 0x3e, 0x37, 0x69, 0xdc, 0x4c, 0x92, 0xca, 0x5d, 0x95, 0x3b, 0x5f, 0x29, 0x34, 0xb2, 0x04,
+	0x0a, 0x42, 0x72, 0xb9, 0x94, 0xeb, 0xf1, 0x02, 0x52, 0x92, 0xfa, 0xd2, 0x88, 0x5c, 0x1a, 0x6d,
+	0x72, 0x3d, 0x40, 0x48, 0xd6, 0x36, 0x5e, 0x1c, 0x0b, 0xc7, 0x6b, 0xd6, 0x9b, 0xa0, 0xfc, 0x2c,
+	0xde, 0x90, 0xee, 0x77, 0xf1, 0x8e, 0xbc, 0x6b, 0x27, 0xa6, 0x69, 0x0f, 0x09, 0xde, 0x3c, 0xdf,
+	0x7c, 0xf3, 0xcd, 0xee, 0x78, 0x66, 0x16, 0xbe, 0xf2, 0x79, 0x3c, 0x3b, 0xbf, 0x0b, 0x22, 0xc2,
+	0xd7, 0x21, 0xf3, 0xcf, 0x53, 0xd3, 0xdd, 0x98, 0xee, 0xea, 0xc5, 0xd6, 0x67, 0xc7, 0x9c, 0x09,
+	0x86, 0x8e, 0x52, 0x8a, 0xbd, 0x45, 0x57, 0x2f, 0x4e, 0x3e, 0xf5, 0x19, 0xf3, 0x43, 0x7a, 0x2e,
+	0x09, 0x77, 0xcb, 0x5f, 0xce, 0xbd, 0x25, 0x27, 0x22, 0x60, 0x91, 0x0a, 0x39, 0x39, 0xbb, 0xef,
+	0x17, 0xc1, 0x82, 0x26, 0x82, 0x2c, 0x62, 0x45, 0xb0, 0xde, 0xeb, 0x50, 0xef, 0xf3, 0x78, 0x36,
+	0x64, 0xbe, 0x13, 0x09, 0xbe, 0x46, 0xdf, 0x40, 0x75, 0xc3, 0x31, 0xb5, 0xa6, 0xd6, 0xaa, 0xb5,
+	0x4f, 0x6c, 0xa5, 0x62, 0xe7, 0x2a, 0xf6, 0x34, 0x67, 0xe0, 0x2d, 0x19, 0x3d, 0x03, 0x7d, 0x46,
+	0xc2, 0xd0, 0x0d, 0x3c, 0x73, 0xaf, 0xa9, 0xb5, 0xca, 0xb8, 0x92, 0x9a, 0x03, 0x0f, 0xbd, 0x84,
+	0x67, 0x09, 0xfd, 0x6d, 0x49, 0xa3, 0x19, 0x75, 0x03, 0xcf, 0xfd, 0x3d, 0x10, 0xf3, 0x20, 0x72,
+	0x53, 0xa7, 0x59, 0x92, 0xc4, 0xe3, 0xdc, 0x3d, 0xf0, 0xde, 0x49, 0x67, 0x8f, 0x84, 0x21, 0xfa,
+	0x16, 0xca, 0x62, 0x1d, 0x53, 0xb3, 0xdc, 0xd4, 0x5a, 0x87, 0xed, 0x2f, 0xec, 0x9d, 0xdb, 0xdb,
+	0xc5, 0x83, 0xdb, 0xce, 0x8a, 0x46, 0x62, 0xba, 0x8e, 0x29, 0x96, 0x61, 0xe8, 0x3b, 0xa8, 0x84,
+	0xcc, 0xf7, 0x29, 0x37, 0xf7, 0xa5, 0xc0, 0xe7, 0xff, 0x26, 0x30, 0x94, 0x6c, 0x9c, 0x45, 0xa1,
+	0xd7, 0xd0, 0x98, 0x85, 0x01, 0x8d, 0x84, 0x3b, 0xa7, 0xc4, 0xa3, 0xdc, 0xac, 0xc8, 0x62, 0x9c,
+	0x3d, 0x20, 0xd3, 0x93, 0xbc, 0x6b, 0x49, 0xbb, 0x7e, 0x82, 0xeb, 0xb3, 0x82, 0x9d, 0xea, 0x24,
+	0x94, 0xaf, 0x28, 0xcf, 0x75, 0xf4, 0x47, 0x75, 0x26, 0x92, 0xb7, 0xd5, 0x49, 0x0a, 0x36, 0xba,
+	0x04, 0x7d, 0x41, 0x93, 0x84, 0xf8, 0xd4, 0x3c, 0xc8, 0x7f, 0xcb, 0x8e, 0xc2, 0x1b, 0xc5, 0xb8,
+	0x7e, 0x82, 0x73, 0x72, 0x1a, 0x27, 0x38, 0x09, 0x42, 0xca, 0xcd, 0xea, 0xa3, 0x71, 0x53, 0xc5,
+	0x48, 0xe3, 0x32, 0x32, 0xfa, 0x12, 0x8e, 0x62, 0xb2, 0x0e, 0x19, 0xf1, 0x5c, 0xc1, 0x97, 0xd1,
+	0x8c, 0x08, 0xea, 0x99, 0xd0, 0xd4, 0x5a, 0x07, 0xd8, 0xc8, 0x1c, 0xd3, 0x1c, 0x47, 0x36, 0x94,
+	0x63, 0x4a, 0xb9, 0x59, 0x7b, 0x34, 0x43, 0xc7, 0xf3, 0x38, 0x4d, 0x12, 0x2c, 0x79, 0xd6, 0x5f,
+	0x1a, 0x54, 0x37, 0x3f, 0x0c, 0x3d, 0x05, 0xe4, 0xdc, 0x3a, 0xa3, 0xa9, 0x3b, 0xfd, 0x71, 0xec,
+	0xb8, 0x6f, 0x47, 0xdf, 0x8f, 0x6e, 0xde, 0x8d, 0x8c, 0x27, 0xe8, 0x14, 0xcc, 0x02, 0xde, 0x1b,
+	0x0e, 0xd2, 0xef, 0x6b, 0xa7, 0x73, 0xe5, 0x60, 0x43, 0xbb, 0xe7, 0x9d, 0x38, 0xf8, 0xd6, 0xc1,
+	0xb9, 0x77, 0x0f, 0x7d, 0x02, 0xcf, 0x77, 0x63, 0xdf, 0x38, 0x93, 0x49, 0xa7, 0xef, 0x18, 0xa5,
+	0x7b, 0xee, 0x2c, 0x38, 0x77, 0x97, 0x51, 0x13, 0x4e, 0x1f, 0xc8, 0xdc, 0x19, 0xbe, 0x76, 0x7b,
+	0xc3, 0x9b, 0x89, 0x63, 0xec, 0x3f, 0x2c, 0x30, 0xc5, 0x9d, 0xc1, 0xd0, 0xc1, 0x46, 0x05, 0x7d,
+	0x04, 0x47, 0x45, 0x81, 0xce, 0xa8, 0xe7, 0x0c, 0x0d, 0xdd, 0xea, 0x42, 0x45, 0xb5, 0x19, 0x42,
+	0x70, 0x38, 0xbc, 0xe9, 0xf7, 0x1d, 0x5c, 0xb8, 0xef, 0x11, 0x34, 0x32, 0x4c, 0x65, 0x34, 0xb4,
+	0x02, 0xa4, 0x52, 0x18, 0x7b, 0xdd, 0x2a, 0xe8, 0x59, 0xfd, 0xad, 0xf7, 0x1a, 0xd4, 0x8b, 0xcd,
+	0x87, 0x5e, 0xc1, 0xc1, 0x82, 0x0a, 0xe2, 0x11, 0x41, 0xb2, 0xe1, 0xfd, 0xf8, 0xc1, 0x2e, 0x51,
+	0x14, 0xbc, 0x21, 0xa3, 0x33, 0xa8, 0x2d, 0xa8, 0x98, 0x33, 0xcf, 0x8d, 0xc8, 0x82, 0xca, 0x01,
+	0xae, 0x62, 0x50, 0xd0, 0x88, 0x2c, 0x28, 0x3a, 0x85, 0x2a, 0x59, 0x8a, 0x39, 0xe3, 0x81, 0x58,
+	0xcb, 0xb1, 0xad, 0xe2, 0x2d, 0x80, 0x2e, 0x40, 0x4f, 0x17, 0x01, 0x5b, 0x0a, 0x39, 0xae, 0xb5,
+	0xf6, 0xf3, 0x9d, 0x9d, 0x71, 0x95, 0x6d, 0x26, 0x9c, 0x33, 0xad, 0x3e, 0xd4, 0x8b, 0x1d, 0xff,
+	0x9f, 0x0f, 0x6f, 0xfd, 0xa1, 0x81, 0x9e, 0x75, 0xf0, 0xff, 0xaa, 0x40, 0x22, 0x88, 0x58, 0x26,
+	0xee, 0x8c, 0x79, 0xaa, 0x02, 0x0d, 0x0c, 0x0a, 0xea, 0x31, 0x8f, 0xa2, 0xcf, 0xe0, 0x30, 0x23,
+	0xe4, 0x73, 0xa8, 0xca, 0xd0, 0x50, 0x68, 0x36, 0x7a, 0x05, 0x9a, 0x47, 0x05, 0x09, 0xc2, 0x44,
+	0x56, 0xa4, 0x9e, 0xd3, 0xae, 0x14, 0x68, 0xbd, 0x04, 0x3d, 0x8f, 0x78, 0x0a, 0x95, 0x90, 0x46,
+	0xbe, 0x98, 0xcb, 0x03, 0x37, 0x70, 0x66, 0x21, 0x04, 0x65, 0x79, 0x8d, 0x3d, 0x19, 0x2f, 0xbf,
+	0xad, 0x2e, 0x1c, 0xe4, 0x67, 0x47, 0x97, 0xb0, 0x4f, 0xd3, 0xcd, 0x65, 0x6a, 0xcd, 0x52, 0xab,
+	0xd6, 0x6e, 0x7e, 0xe0, 0x9e, 0x72, 0xc3, 0x61, 0x45, 0xb7, 0x5e, 0x41, 0xe3, 0x1f, 0x38, 0x32,
+	0xa0, 0xf4, 0x2b, 0x5d, 0xcb, 0xec, 0x55, 0x9c, 0x7e, 0xa2, 0x63, 0xd8, 0x5f, 0x91, 0x70, 0x49,
+	0xb3, 0xdc, 0xca, 0xb0, 0xfe, 0xd4, 0x40, 0xcf, 0xe6, 0x18, 0x5d, 0x64, 0xdb, 0x59, 0x93, 0xcb,
+	0xf5, 0xec, 0xf1, 0x89, 0xb7, 0x0b, 0x3b, 0xd9, 0x04, 0x9d, 0x28, 0x34, 0xeb, 0xb0, 0xdc, 0x4c,
+	0x1f, 0x8f, 0x20, 0x76, 0x63, 0xc6, 0x85, 0xac, 0x6a, 0x03, 0x57, 0x82, 0x78, 0xcc, 0xb8, 0xb0,
+	0x1c, 0x28, 0xcb, 0x1d, 0x61, 0x40, 0xfd, 0xde, 0x76, 0x68, 0x40, 0x55, 0x22, 0x83, 0xf1, 0xed,
+	0xd7, 0x86, 0x56, 0x34, 0x2f, 0x8d, 0xbd, 0x8d, 0xf9, 0x76, 0x34, 0xf8, 0xc1, 0x28, 0x75, 0x7f,
+	0x86, 0xe3, 0x80, 0xed, 0x1e, 0xb2, 0x7b, 0xd8, 0x95, 0xd6, 0x90, 0xf9, 0xe3, 0xb4, 0x51, 0xc7,
+	0xda, 0x4f, 0xed, 0xac, 0x71, 0x7d, 0x16, 0x92, 0xc8, 0xb7, 0x19, 0x57, 0x4f, 0xf3, 0x87, 0x5e,
+	0xea, 0xbb, 0x8a, 0xec, 0xf2, 0x8b, 0xbf, 0x03, 0x00, 0x00, 0xff, 0xff, 0xe7, 0xf6, 0x4b, 0x50,
+	0xd4, 0x07, 0x00, 0x00,
+}
diff --git a/vendor/google.golang.org/grpc/call.go b/vendor/google.golang.org/grpc/call.go
index 180d79d0..9e20e4d3 100644
--- a/vendor/google.golang.org/grpc/call.go
+++ b/vendor/google.golang.org/grpc/call.go
@@ -19,7 +19,7 @@
 package grpc
 
 import (
-	"golang.org/x/net/context"
+	"context"
 )
 
 // Invoke sends the RPC request on the wire and returns after response is
@@ -40,7 +40,7 @@ func (cc *ClientConn) Invoke(ctx context.Context, method string, args, reply int
 func combine(o1 []CallOption, o2 []CallOption) []CallOption {
 	// we don't use append because o1 could have extra capacity whose
 	// elements would be overwritten, which could cause inadvertent
-	// sharing (and race connditions) between concurrent calls
+	// sharing (and race conditions) between concurrent calls
 	if len(o1) == 0 {
 		return o2
 	} else if len(o2) == 0 {
diff --git a/vendor/google.golang.org/grpc/clientconn.go b/vendor/google.golang.org/grpc/clientconn.go
index 9b035e8f..a7643df7 100644
--- a/vendor/google.golang.org/grpc/clientconn.go
+++ b/vendor/google.golang.org/grpc/clientconn.go
@@ -19,6 +19,7 @@
 package grpc
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"math"
@@ -29,8 +30,6 @@ import (
 	"sync/atomic"
 	"time"
 
-	"golang.org/x/net/context"
-	"golang.org/x/net/trace"
 	"google.golang.org/grpc/balancer"
 	_ "google.golang.org/grpc/balancer/roundrobin" // To register roundrobin.
 	"google.golang.org/grpc/codes"
@@ -39,11 +38,13 @@ import (
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal/backoff"
 	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/internal/grpcsync"
 	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/resolver"
 	_ "google.golang.org/grpc/resolver/dns"         // To register dns resolver.
 	_ "google.golang.org/grpc/resolver/passthrough" // To register passthrough resolver.
+	"google.golang.org/grpc/serviceconfig"
 	"google.golang.org/grpc/status"
 )
 
@@ -65,15 +66,11 @@ var (
 	errConnDrain = errors.New("grpc: the connection is drained")
 	// errConnClosing indicates that the connection is closing.
 	errConnClosing = errors.New("grpc: the connection is closing")
-	// errConnUnavailable indicates that the connection is unavailable.
-	errConnUnavailable = errors.New("grpc: the connection is unavailable")
 	// errBalancerClosed indicates that the balancer is closed.
 	errBalancerClosed = errors.New("grpc: balancer is closed")
-	// We use an accessor so that minConnectTimeout can be
-	// atomically read and updated while testing.
-	getMinConnectTimeout = func() time.Duration {
-		return minConnectTimeout
-	}
+	// invalidDefaultServiceConfigErrPrefix is used to prefix the json parsing error for the default
+	// service config.
+	invalidDefaultServiceConfigErrPrefix = "grpc: the provided default service config is invalid"
 )
 
 // The following errors are returned from Dial and DialContext
@@ -82,15 +79,16 @@ var (
 	// being set for ClientConn. Users should either set one or explicitly
 	// call WithInsecure DialOption to disable security.
 	errNoTransportSecurity = errors.New("grpc: no transport security set (use grpc.WithInsecure() explicitly or set credentials)")
+	// errTransportCredsAndBundle indicates that creds bundle is used together
+	// with other individual Transport Credentials.
+	errTransportCredsAndBundle = errors.New("grpc: credentials.Bundle may not be used with individual TransportCredentials")
 	// errTransportCredentialsMissing indicates that users want to transmit security
-	// information (e.g., oauth2 token) which requires secure connection on an insecure
+	// information (e.g., OAuth2 token) which requires secure connection on an insecure
 	// connection.
 	errTransportCredentialsMissing = errors.New("grpc: the credentials require transport level security (use grpc.WithTransportCredentials() to set)")
 	// errCredentialsConflict indicates that grpc.WithTransportCredentials()
 	// and grpc.WithInsecure() are both called for a connection.
 	errCredentialsConflict = errors.New("grpc: transport credentials are set for an insecure connection (grpc.WithTransportCredentials() and grpc.WithInsecure() are both called)")
-	// errNetworkIO indicates that the connection is down due to some network I/O error.
-	errNetworkIO = errors.New("grpc: failed with network I/O error")
 )
 
 const (
@@ -101,12 +99,6 @@ const (
 	defaultReadBufSize  = 32 * 1024
 )
 
-// RegisterChannelz turns on channelz service.
-// This is an EXPERIMENTAL API.
-func RegisterChannelz() {
-	channelz.TurnOn()
-}
-
 // Dial creates a client connection to the given target.
 func Dial(target string, opts ...DialOption) (*ClientConn, error) {
 	return DialContext(context.Background(), target, opts...)
@@ -130,11 +122,13 @@ func Dial(target string, opts ...DialOption) (*ClientConn, error) {
 // e.g. to use dns resolver, a "dns:///" prefix should be applied to the target.
 func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *ClientConn, err error) {
 	cc := &ClientConn{
-		target:         target,
-		csMgr:          &connectivityStateManager{},
-		conns:          make(map[*addrConn]struct{}),
-		dopts:          defaultDialOptions(),
-		blockingpicker: newPickerWrapper(),
+		target:            target,
+		csMgr:             &connectivityStateManager{},
+		conns:             make(map[*addrConn]struct{}),
+		dopts:             defaultDialOptions(),
+		blockingpicker:    newPickerWrapper(),
+		czData:            new(channelzData),
+		firstResolveEvent: grpcsync.NewEvent(),
 	}
 	cc.retryThrottler.Store((*retryThrottler)(nil))
 	cc.ctx, cc.cancel = context.WithCancel(context.Background())
@@ -143,20 +137,45 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		opt.apply(&cc.dopts)
 	}
 
+	chainUnaryClientInterceptors(cc)
+	chainStreamClientInterceptors(cc)
+
+	defer func() {
+		if err != nil {
+			cc.Close()
+		}
+	}()
+
 	if channelz.IsOn() {
 		if cc.dopts.channelzParentID != 0 {
-			cc.channelzID = channelz.RegisterChannel(cc, cc.dopts.channelzParentID, target)
+			cc.channelzID = channelz.RegisterChannel(&channelzChannel{cc}, cc.dopts.channelzParentID, target)
+			channelz.AddTraceEvent(cc.channelzID, &channelz.TraceEventDesc{
+				Desc:     "Channel Created",
+				Severity: channelz.CtINFO,
+				Parent: &channelz.TraceEventDesc{
+					Desc:     fmt.Sprintf("Nested Channel(id:%d) created", cc.channelzID),
+					Severity: channelz.CtINFO,
+				},
+			})
 		} else {
-			cc.channelzID = channelz.RegisterChannel(cc, 0, target)
+			cc.channelzID = channelz.RegisterChannel(&channelzChannel{cc}, 0, target)
+			channelz.AddTraceEvent(cc.channelzID, &channelz.TraceEventDesc{
+				Desc:     "Channel Created",
+				Severity: channelz.CtINFO,
+			})
 		}
+		cc.csMgr.channelzID = cc.channelzID
 	}
 
 	if !cc.dopts.insecure {
-		if cc.dopts.copts.TransportCredentials == nil {
+		if cc.dopts.copts.TransportCredentials == nil && cc.dopts.copts.CredsBundle == nil {
 			return nil, errNoTransportSecurity
 		}
+		if cc.dopts.copts.TransportCredentials != nil && cc.dopts.copts.CredsBundle != nil {
+			return nil, errTransportCredsAndBundle
+		}
 	} else {
-		if cc.dopts.copts.TransportCredentials != nil {
+		if cc.dopts.copts.TransportCredentials != nil || cc.dopts.copts.CredsBundle != nil {
 			return nil, errCredentialsConflict
 		}
 		for _, cd := range cc.dopts.copts.PerRPCCredentials {
@@ -166,13 +185,20 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		}
 	}
 
+	if cc.dopts.defaultServiceConfigRawJSON != nil {
+		sc, err := parseServiceConfig(*cc.dopts.defaultServiceConfigRawJSON)
+		if err != nil {
+			return nil, fmt.Errorf("%s: %v", invalidDefaultServiceConfigErrPrefix, err)
+		}
+		cc.dopts.defaultServiceConfig = sc
+	}
 	cc.mkp = cc.dopts.copts.KeepaliveParams
 
 	if cc.dopts.copts.Dialer == nil {
 		cc.dopts.copts.Dialer = newProxyDialer(
 			func(ctx context.Context, addr string) (net.Conn, error) {
 				network, addr := parseDialTarget(addr)
-				return dialContext(ctx, network, addr)
+				return (&net.Dialer{}).DialContext(ctx, network, addr)
 			},
 		)
 	}
@@ -188,17 +214,12 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		ctx, cancel = context.WithTimeout(ctx, cc.dopts.timeout)
 		defer cancel()
 	}
-
 	defer func() {
 		select {
 		case <-ctx.Done():
 			conn, err = nil, ctx.Err()
 		default:
 		}
-
-		if err != nil {
-			cc.Close()
-		}
 	}()
 
 	scSet := false
@@ -207,7 +228,7 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		select {
 		case sc, ok := <-cc.dopts.scChan:
 			if ok {
-				cc.sc = sc
+				cc.sc = &sc
 				scSet = true
 			}
 		default:
@@ -224,9 +245,9 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		grpclog.Infof("parsed scheme: %q", cc.parsedTarget.Scheme)
 		cc.dopts.resolverBuilder = resolver.Get(cc.parsedTarget.Scheme)
 		if cc.dopts.resolverBuilder == nil {
-			// If resolver builder is still nil, the parse target's scheme is
+			// If resolver builder is still nil, the parsed target's scheme is
 			// not registered. Fallback to default resolver and set Endpoint to
-			// the original unparsed target.
+			// the original target.
 			grpclog.Infof("scheme %q not registered, fallback to default scheme", cc.parsedTarget.Scheme)
 			cc.parsedTarget = resolver.Target{
 				Scheme:   resolver.GetDefaultScheme(),
@@ -253,7 +274,7 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		select {
 		case sc, ok := <-cc.dopts.scChan:
 			if ok {
-				cc.sc = sc
+				cc.sc = &sc
 			}
 		case <-ctx.Done():
 			return nil, ctx.Err()
@@ -269,30 +290,36 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 	}
 	cc.balancerBuildOpts = balancer.BuildOptions{
 		DialCreds:        credsClone,
+		CredsBundle:      cc.dopts.copts.CredsBundle,
 		Dialer:           cc.dopts.copts.Dialer,
 		ChannelzParentID: cc.channelzID,
+		Target:           cc.parsedTarget,
 	}
 
 	// Build the resolver.
-	cc.resolverWrapper, err = newCCResolverWrapper(cc)
+	rWrapper, err := newCCResolverWrapper(cc)
 	if err != nil {
 		return nil, fmt.Errorf("failed to build resolver: %v", err)
 	}
-	// Start the resolver wrapper goroutine after resolverWrapper is created.
-	//
-	// If the goroutine is started before resolverWrapper is ready, the
-	// following may happen: The goroutine sends updates to cc. cc forwards
-	// those to balancer. Balancer creates new addrConn. addrConn fails to
-	// connect, and calls resolveNow(). resolveNow() tries to use the non-ready
-	// resolverWrapper.
-	cc.resolverWrapper.start()
 
+	cc.mu.Lock()
+	cc.resolverWrapper = rWrapper
+	cc.mu.Unlock()
 	// A blocking dial blocks until the clientConn is ready.
 	if cc.dopts.block {
 		for {
 			s := cc.GetState()
 			if s == connectivity.Ready {
 				break
+			} else if cc.dopts.copts.FailOnNonTempDialError && s == connectivity.TransientFailure {
+				if err = cc.blockingpicker.connectionError(); err != nil {
+					terr, ok := err.(interface {
+						Temporary() bool
+					})
+					if ok && !terr.Temporary() {
+						return nil, err
+					}
+				}
 			}
 			if !cc.WaitForStateChange(ctx, s) {
 				// ctx got timeout or canceled.
@@ -304,12 +331,75 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 	return cc, nil
 }
 
+// chainUnaryClientInterceptors chains all unary client interceptors into one.
+func chainUnaryClientInterceptors(cc *ClientConn) {
+	interceptors := cc.dopts.chainUnaryInts
+	// Prepend dopts.unaryInt to the chaining interceptors if it exists, since unaryInt will
+	// be executed before any other chained interceptors.
+	if cc.dopts.unaryInt != nil {
+		interceptors = append([]UnaryClientInterceptor{cc.dopts.unaryInt}, interceptors...)
+	}
+	var chainedInt UnaryClientInterceptor
+	if len(interceptors) == 0 {
+		chainedInt = nil
+	} else if len(interceptors) == 1 {
+		chainedInt = interceptors[0]
+	} else {
+		chainedInt = func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, invoker UnaryInvoker, opts ...CallOption) error {
+			return interceptors[0](ctx, method, req, reply, cc, getChainUnaryInvoker(interceptors, 0, invoker), opts...)
+		}
+	}
+	cc.dopts.unaryInt = chainedInt
+}
+
+// getChainUnaryInvoker recursively generate the chained unary invoker.
+func getChainUnaryInvoker(interceptors []UnaryClientInterceptor, curr int, finalInvoker UnaryInvoker) UnaryInvoker {
+	if curr == len(interceptors)-1 {
+		return finalInvoker
+	}
+	return func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, opts ...CallOption) error {
+		return interceptors[curr+1](ctx, method, req, reply, cc, getChainUnaryInvoker(interceptors, curr+1, finalInvoker), opts...)
+	}
+}
+
+// chainStreamClientInterceptors chains all stream client interceptors into one.
+func chainStreamClientInterceptors(cc *ClientConn) {
+	interceptors := cc.dopts.chainStreamInts
+	// Prepend dopts.streamInt to the chaining interceptors if it exists, since streamInt will
+	// be executed before any other chained interceptors.
+	if cc.dopts.streamInt != nil {
+		interceptors = append([]StreamClientInterceptor{cc.dopts.streamInt}, interceptors...)
+	}
+	var chainedInt StreamClientInterceptor
+	if len(interceptors) == 0 {
+		chainedInt = nil
+	} else if len(interceptors) == 1 {
+		chainedInt = interceptors[0]
+	} else {
+		chainedInt = func(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, streamer Streamer, opts ...CallOption) (ClientStream, error) {
+			return interceptors[0](ctx, desc, cc, method, getChainStreamer(interceptors, 0, streamer), opts...)
+		}
+	}
+	cc.dopts.streamInt = chainedInt
+}
+
+// getChainStreamer recursively generate the chained client stream constructor.
+func getChainStreamer(interceptors []StreamClientInterceptor, curr int, finalStreamer Streamer) Streamer {
+	if curr == len(interceptors)-1 {
+		return finalStreamer
+	}
+	return func(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (ClientStream, error) {
+		return interceptors[curr+1](ctx, desc, cc, method, getChainStreamer(interceptors, curr+1, finalStreamer), opts...)
+	}
+}
+
 // connectivityStateManager keeps the connectivity.State of ClientConn.
 // This struct will eventually be exported so the balancers can access it.
 type connectivityStateManager struct {
 	mu         sync.Mutex
 	state      connectivity.State
 	notifyChan chan struct{}
+	channelzID int64
 }
 
 // updateState updates the connectivity.State of ClientConn.
@@ -325,6 +415,12 @@ func (csm *connectivityStateManager) updateState(state connectivity.State) {
 		return
 	}
 	csm.state = state
+	if channelz.IsOn() {
+		channelz.AddTraceEvent(csm.channelzID, &channelz.TraceEventDesc{
+			Desc:     fmt.Sprintf("Channel Connectivity change to %v", state),
+			Severity: channelz.CtINFO,
+		})
+	}
 	if csm.notifyChan != nil {
 		// There are other goroutines waiting on this channel.
 		close(csm.notifyChan)
@@ -359,27 +455,22 @@ type ClientConn struct {
 	csMgr        *connectivityStateManager
 
 	balancerBuildOpts balancer.BuildOptions
-	resolverWrapper   *ccResolverWrapper
 	blockingpicker    *pickerWrapper
 
-	mu    sync.RWMutex
-	sc    ServiceConfig
-	scRaw string
-	conns map[*addrConn]struct{}
+	mu              sync.RWMutex
+	resolverWrapper *ccResolverWrapper
+	sc              *ServiceConfig
+	conns           map[*addrConn]struct{}
 	// Keepalive parameter can be updated if a GoAway is received.
 	mkp             keepalive.ClientParameters
 	curBalancerName string
-	preBalancerName string // previous balancer name.
-	curAddresses    []resolver.Address
 	balancerWrapper *ccBalancerWrapper
 	retryThrottler  atomic.Value
 
-	channelzID          int64 // channelz unique identification number
-	czmu                sync.RWMutex
-	callsStarted        int64
-	callsSucceeded      int64
-	callsFailed         int64
-	lastCallStartedTime time.Time
+	firstResolveEvent *grpcsync.Event
+
+	channelzID int64 // channelz unique identification number
+	czData     *channelzData
 }
 
 // WaitForStateChange waits until the connectivity.State of ClientConn changes from sourceState or
@@ -413,9 +504,8 @@ func (cc *ClientConn) scWatcher() {
 			}
 			cc.mu.Lock()
 			// TODO: load balance policy runtime change is ignored.
-			// We may revist this decision in the future.
-			cc.sc = sc
-			cc.scRaw = ""
+			// We may revisit this decision in the future.
+			cc.sc = &sc
 			cc.mu.Unlock()
 		case <-cc.ctx.Done():
 			return
@@ -423,47 +513,64 @@ func (cc *ClientConn) scWatcher() {
 	}
 }
 
-func (cc *ClientConn) handleResolvedAddrs(addrs []resolver.Address, err error) {
+// waitForResolvedAddrs blocks until the resolver has provided addresses or the
+// context expires.  Returns nil unless the context expires first; otherwise
+// returns a status error based on the context.
+func (cc *ClientConn) waitForResolvedAddrs(ctx context.Context) error {
+	// This is on the RPC path, so we use a fast path to avoid the
+	// more-expensive "select" below after the resolver has returned once.
+	if cc.firstResolveEvent.HasFired() {
+		return nil
+	}
+	select {
+	case <-cc.firstResolveEvent.Done():
+		return nil
+	case <-ctx.Done():
+		return status.FromContextError(ctx.Err()).Err()
+	case <-cc.ctx.Done():
+		return ErrClientConnClosing
+	}
+}
+
+func (cc *ClientConn) updateResolverState(s resolver.State) error {
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
+	// Check if the ClientConn is already closed. Some fields (e.g.
+	// balancerWrapper) are set to nil when closing the ClientConn, and could
+	// cause nil pointer panic if we don't have this check.
 	if cc.conns == nil {
-		// cc was closed.
-		return
+		return nil
 	}
 
-	if reflect.DeepEqual(cc.curAddresses, addrs) {
-		return
+	if cc.dopts.disableServiceConfig || s.ServiceConfig == nil {
+		if cc.dopts.defaultServiceConfig != nil && cc.sc == nil {
+			cc.applyServiceConfig(cc.dopts.defaultServiceConfig)
+		}
+	} else if sc, ok := s.ServiceConfig.(*ServiceConfig); ok {
+		cc.applyServiceConfig(sc)
 	}
 
-	cc.curAddresses = addrs
-
+	var balCfg serviceconfig.LoadBalancingConfig
 	if cc.dopts.balancerBuilder == nil {
 		// Only look at balancer types and switch balancer if balancer dial
 		// option is not set.
-		var isGRPCLB bool
-		for _, a := range addrs {
-			if a.Type == resolver.GRPCLB {
-				isGRPCLB = true
-				break
-			}
-		}
 		var newBalancerName string
-		if isGRPCLB {
-			newBalancerName = grpclbName
+		if cc.sc != nil && cc.sc.lbConfig != nil {
+			newBalancerName = cc.sc.lbConfig.name
+			balCfg = cc.sc.lbConfig.cfg
 		} else {
-			// Address list doesn't contain grpclb address. Try to pick a
-			// non-grpclb balancer.
-			newBalancerName = cc.curBalancerName
-			// If current balancer is grpclb, switch to the previous one.
-			if newBalancerName == grpclbName {
-				newBalancerName = cc.preBalancerName
+			var isGRPCLB bool
+			for _, a := range s.Addresses {
+				if a.Type == resolver.GRPCLB {
+					isGRPCLB = true
+					break
+				}
 			}
-			// The following could be true in two cases:
-			// - the first time handling resolved addresses
-			//   (curBalancerName="")
-			// - the first time handling non-grpclb addresses
-			//   (curBalancerName="grpclb", preBalancerName="")
-			if newBalancerName == "" {
+			if isGRPCLB {
+				newBalancerName = grpclbName
+			} else if cc.sc != nil && cc.sc.LB != nil {
+				newBalancerName = *cc.sc.LB
+			} else {
 				newBalancerName = PickFirstBalancerName
 			}
 		}
@@ -471,10 +578,12 @@ func (cc *ClientConn) handleResolvedAddrs(addrs []resolver.Address, err error) {
 	} else if cc.balancerWrapper == nil {
 		// Balancer dial option was set, and this is the first time handling
 		// resolved addresses. Build a balancer with dopts.balancerBuilder.
+		cc.curBalancerName = cc.dopts.balancerBuilder.Name()
 		cc.balancerWrapper = newCCBalancerWrapper(cc, cc.dopts.balancerBuilder, cc.balancerBuildOpts)
 	}
 
-	cc.balancerWrapper.handleResolvedAddrs(addrs, nil)
+	cc.balancerWrapper.updateClientConnState(&balancer.ClientConnState{ResolverState: s, BalancerConfig: balCfg})
+	return nil
 }
 
 // switchBalancer starts the switching from current balancer to the balancer
@@ -486,11 +595,7 @@ func (cc *ClientConn) handleResolvedAddrs(addrs []resolver.Address, err error) {
 //
 // Caller must hold cc.mu.
 func (cc *ClientConn) switchBalancer(name string) {
-	if cc.conns == nil {
-		return
-	}
-
-	if strings.ToLower(cc.curBalancerName) == strings.ToLower(name) {
+	if strings.EqualFold(cc.curBalancerName, name) {
 		return
 	}
 
@@ -499,18 +604,29 @@ func (cc *ClientConn) switchBalancer(name string) {
 		grpclog.Infoln("ignoring balancer switching: Balancer DialOption used instead")
 		return
 	}
-	// TODO(bar switching) change this to two steps: drain and close.
-	// Keep track of sc in wrapper.
 	if cc.balancerWrapper != nil {
 		cc.balancerWrapper.close()
 	}
 
 	builder := balancer.Get(name)
+	if channelz.IsOn() {
+		if builder == nil {
+			channelz.AddTraceEvent(cc.channelzID, &channelz.TraceEventDesc{
+				Desc:     fmt.Sprintf("Channel switches to new LB policy %q due to fallback from invalid balancer name", PickFirstBalancerName),
+				Severity: channelz.CtWarning,
+			})
+		} else {
+			channelz.AddTraceEvent(cc.channelzID, &channelz.TraceEventDesc{
+				Desc:     fmt.Sprintf("Channel switches to new LB policy %q", name),
+				Severity: channelz.CtINFO,
+			})
+		}
+	}
 	if builder == nil {
 		grpclog.Infof("failed to get balancer builder for: %v, using pick_first instead", name)
 		builder = newPickfirstBuilder()
 	}
-	cc.preBalancerName = cc.curBalancerName
+
 	cc.curBalancerName = builder.Name()
 	cc.balancerWrapper = newCCBalancerWrapper(cc, builder, cc.balancerBuildOpts)
 }
@@ -530,11 +646,14 @@ func (cc *ClientConn) handleSubConnStateChange(sc balancer.SubConn, s connectivi
 // newAddrConn creates an addrConn for addrs and adds it to cc.conns.
 //
 // Caller needs to make sure len(addrs) > 0.
-func (cc *ClientConn) newAddrConn(addrs []resolver.Address) (*addrConn, error) {
+func (cc *ClientConn) newAddrConn(addrs []resolver.Address, opts balancer.NewSubConnOptions) (*addrConn, error) {
 	ac := &addrConn{
-		cc:    cc,
-		addrs: addrs,
-		dopts: cc.dopts,
+		cc:           cc,
+		addrs:        addrs,
+		scopts:       opts,
+		dopts:        cc.dopts,
+		czData:       new(channelzData),
+		resetBackoff: make(chan struct{}),
 	}
 	ac.ctx, ac.cancel = context.WithCancel(cc.ctx)
 	// Track ac in cc. This needs to be done before any getTransport(...) is called.
@@ -545,6 +664,14 @@ func (cc *ClientConn) newAddrConn(addrs []resolver.Address) (*addrConn, error) {
 	}
 	if channelz.IsOn() {
 		ac.channelzID = channelz.RegisterSubChannel(ac, cc.channelzID, "")
+		channelz.AddTraceEvent(ac.channelzID, &channelz.TraceEventDesc{
+			Desc:     "Subchannel Created",
+			Severity: channelz.CtINFO,
+			Parent: &channelz.TraceEventDesc{
+				Desc:     fmt.Sprintf("Subchannel(id:%d) created", ac.channelzID),
+				Severity: channelz.CtINFO,
+			},
+		})
 	}
 	cc.conns[ac] = struct{}{}
 	cc.mu.Unlock()
@@ -564,19 +691,14 @@ func (cc *ClientConn) removeAddrConn(ac *addrConn, err error) {
 	ac.tearDown(err)
 }
 
-// ChannelzMetric returns ChannelInternalMetric of current ClientConn.
-// This is an EXPERIMENTAL API.
-func (cc *ClientConn) ChannelzMetric() *channelz.ChannelInternalMetric {
-	state := cc.GetState()
-	cc.czmu.RLock()
-	defer cc.czmu.RUnlock()
+func (cc *ClientConn) channelzMetric() *channelz.ChannelInternalMetric {
 	return &channelz.ChannelInternalMetric{
-		State:                    state,
+		State:                    cc.GetState(),
 		Target:                   cc.target,
-		CallsStarted:             cc.callsStarted,
-		CallsSucceeded:           cc.callsSucceeded,
-		CallsFailed:              cc.callsFailed,
-		LastCallStartedTimestamp: cc.lastCallStartedTime,
+		CallsStarted:             atomic.LoadInt64(&cc.czData.callsStarted),
+		CallsSucceeded:           atomic.LoadInt64(&cc.czData.callsSucceeded),
+		CallsFailed:              atomic.LoadInt64(&cc.czData.callsFailed),
+		LastCallStartedTimestamp: time.Unix(0, atomic.LoadInt64(&cc.czData.lastCallStartedTime)),
 	}
 }
 
@@ -587,30 +709,21 @@ func (cc *ClientConn) Target() string {
 }
 
 func (cc *ClientConn) incrCallsStarted() {
-	cc.czmu.Lock()
-	cc.callsStarted++
-	// TODO(yuxuanli): will make this a time.Time pointer improve performance?
-	cc.lastCallStartedTime = time.Now()
-	cc.czmu.Unlock()
+	atomic.AddInt64(&cc.czData.callsStarted, 1)
+	atomic.StoreInt64(&cc.czData.lastCallStartedTime, time.Now().UnixNano())
 }
 
 func (cc *ClientConn) incrCallsSucceeded() {
-	cc.czmu.Lock()
-	cc.callsSucceeded++
-	cc.czmu.Unlock()
+	atomic.AddInt64(&cc.czData.callsSucceeded, 1)
 }
 
 func (cc *ClientConn) incrCallsFailed() {
-	cc.czmu.Lock()
-	cc.callsFailed++
-	cc.czmu.Unlock()
+	atomic.AddInt64(&cc.czData.callsFailed, 1)
 }
 
-// connect starts to creating transport and also starts the transport monitor
-// goroutine for this ac.
+// connect starts creating a transport.
 // It does nothing if the ac is not IDLE.
 // TODO(bar) Move this to the addrConn section.
-// This was part of resetAddrConn, keep it here to make the diff look clean.
 func (ac *addrConn) connect() error {
 	ac.mu.Lock()
 	if ac.state == connectivity.Shutdown {
@@ -621,28 +734,28 @@ func (ac *addrConn) connect() error {
 		ac.mu.Unlock()
 		return nil
 	}
-	ac.state = connectivity.Connecting
-	ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
+	// Update connectivity state within the lock to prevent subsequent or
+	// concurrent calls from resetting the transport more than once.
+	ac.updateConnectivityState(connectivity.Connecting)
 	ac.mu.Unlock()
 
 	// Start a goroutine connecting to the server asynchronously.
-	go func() {
-		if err := ac.resetTransport(); err != nil {
-			grpclog.Warningf("Failed to dial %s: %v; please retry.", ac.addrs[0].Addr, err)
-			if err != errConnClosing {
-				// Keep this ac in cc.conns, to get the reason it's torn down.
-				ac.tearDown(err)
-			}
-			return
-		}
-		ac.transportMonitor()
-	}()
+	go ac.resetTransport()
 	return nil
 }
 
 // tryUpdateAddrs tries to update ac.addrs with the new addresses list.
 //
-// It checks whether current connected address of ac is in the new addrs list.
+// If ac is Connecting, it returns false. The caller should tear down the ac and
+// create a new one. Note that the backoff will be reset when this happens.
+//
+// If ac is TransientFailure, it updates ac.addrs and returns true. The updated
+// addresses will be picked up by retry in the next iteration after backoff.
+//
+// If ac is Shutdown or Idle, it updates ac.addrs and returns true.
+//
+// If ac is Ready, it checks whether current connected address of ac is in the
+// new addrs list.
 //  - If true, it updates ac.addrs and returns true. The ac will keep using
 //    the existing connection.
 //  - If false, it does nothing and returns false.
@@ -650,11 +763,18 @@ func (ac *addrConn) tryUpdateAddrs(addrs []resolver.Address) bool {
 	ac.mu.Lock()
 	defer ac.mu.Unlock()
 	grpclog.Infof("addrConn: tryUpdateAddrs curAddr: %v, addrs: %v", ac.curAddr, addrs)
-	if ac.state == connectivity.Shutdown {
+	if ac.state == connectivity.Shutdown ||
+		ac.state == connectivity.TransientFailure ||
+		ac.state == connectivity.Idle {
 		ac.addrs = addrs
 		return true
 	}
 
+	if ac.state == connectivity.Connecting {
+		return false
+	}
+
+	// ac.state is Ready, try to find the connected address.
 	var curAddrFound bool
 	for _, a := range addrs {
 		if reflect.DeepEqual(ac.curAddr, a) {
@@ -665,7 +785,6 @@ func (ac *addrConn) tryUpdateAddrs(addrs []resolver.Address) bool {
 	grpclog.Infof("addrConn: tryUpdateAddrs curAddrFound: %v", curAddrFound)
 	if curAddrFound {
 		ac.addrs = addrs
-		ac.reconnectIdx = 0 // Start reconnecting from beginning in the new list.
 	}
 
 	return curAddrFound
@@ -682,6 +801,9 @@ func (cc *ClientConn) GetMethodConfig(method string) MethodConfig {
 	// TODO: Avoid the locking here.
 	cc.mu.RLock()
 	defer cc.mu.RUnlock()
+	if cc.sc == nil {
+		return MethodConfig{}
+	}
 	m, ok := cc.sc.Methods[method]
 	if !ok {
 		i := strings.LastIndex(method, "/")
@@ -690,6 +812,15 @@ func (cc *ClientConn) GetMethodConfig(method string) MethodConfig {
 	return m
 }
 
+func (cc *ClientConn) healthCheckConfig() *healthCheckConfig {
+	cc.mu.RLock()
+	defer cc.mu.RUnlock()
+	if cc.sc == nil {
+		return nil
+	}
+	return cc.sc.healthCheckConfig
+}
+
 func (cc *ClientConn) getTransport(ctx context.Context, failfast bool, method string) (transport.ClientTransport, func(balancer.DoneInfo), error) {
 	t, done, err := cc.blockingpicker.pick(ctx, failfast, balancer.PickOptions{
 		FullMethodName: method,
@@ -700,47 +831,25 @@ func (cc *ClientConn) getTransport(ctx context.Context, failfast bool, method st
 	return t, done, nil
 }
 
-// handleServiceConfig parses the service config string in JSON format to Go native
-// struct ServiceConfig, and store both the struct and the JSON string in ClientConn.
-func (cc *ClientConn) handleServiceConfig(js string) error {
-	if cc.dopts.disableServiceConfig {
-		return nil
-	}
-	sc, err := parseServiceConfig(js)
-	if err != nil {
-		return err
+func (cc *ClientConn) applyServiceConfig(sc *ServiceConfig) error {
+	if sc == nil {
+		// should never reach here.
+		return fmt.Errorf("got nil pointer for service config")
 	}
-	cc.mu.Lock()
-	cc.scRaw = js
 	cc.sc = sc
 
-	if sc.retryThrottling != nil {
+	if cc.sc.retryThrottling != nil {
 		newThrottler := &retryThrottler{
-			tokens: sc.retryThrottling.MaxTokens,
-			max:    sc.retryThrottling.MaxTokens,
-			thresh: sc.retryThrottling.MaxTokens / 2,
-			ratio:  sc.retryThrottling.TokenRatio,
+			tokens: cc.sc.retryThrottling.MaxTokens,
+			max:    cc.sc.retryThrottling.MaxTokens,
+			thresh: cc.sc.retryThrottling.MaxTokens / 2,
+			ratio:  cc.sc.retryThrottling.TokenRatio,
 		}
 		cc.retryThrottler.Store(newThrottler)
 	} else {
 		cc.retryThrottler.Store((*retryThrottler)(nil))
 	}
 
-	if sc.LB != nil && *sc.LB != grpclbName { // "grpclb" is not a valid balancer option in service config.
-		if cc.curBalancerName == grpclbName {
-			// If current balancer is grpclb, there's at least one grpclb
-			// balancer address in the resolved list. Don't switch the balancer,
-			// but change the previous balancer name, so if a new resolved
-			// address list doesn't contain grpclb address, balancer will be
-			// switched to *sc.LB.
-			cc.preBalancerName = *sc.LB
-		} else {
-			cc.switchBalancer(*sc.LB)
-			cc.balancerWrapper.handleResolvedAddrs(cc.curAddresses, nil)
-		}
-	}
-
-	cc.mu.Unlock()
 	return nil
 }
 
@@ -754,6 +863,24 @@ func (cc *ClientConn) resolveNow(o resolver.ResolveNowOption) {
 	go r.resolveNow(o)
 }
 
+// ResetConnectBackoff wakes up all subchannels in transient failure and causes
+// them to attempt another connection immediately.  It also resets the backoff
+// times used for subsequent attempts regardless of the current state.
+//
+// In general, this function should not be used.  Typical service or network
+// outages result in a reasonable client reconnection strategy by default.
+// However, if a previously unavailable network becomes available, this may be
+// used to trigger an immediate reconnect.
+//
+// This API is EXPERIMENTAL.
+func (cc *ClientConn) ResetConnectBackoff() {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	for ac := range cc.conns {
+		ac.resetConnectBackoff()
+	}
+}
+
 // Close tears down the ClientConn and all underlying connections.
 func (cc *ClientConn) Close() error {
 	defer cc.cancel()
@@ -786,6 +913,19 @@ func (cc *ClientConn) Close() error {
 		ac.tearDown(ErrClientConnClosing)
 	}
 	if channelz.IsOn() {
+		ted := &channelz.TraceEventDesc{
+			Desc:     "Channel Deleted",
+			Severity: channelz.CtINFO,
+		}
+		if cc.dopts.channelzParentID != 0 {
+			ted.Parent = &channelz.TraceEventDesc{
+				Desc:     fmt.Sprintf("Nested channel(id:%d) deleted", cc.channelzID),
+				Severity: channelz.CtINFO,
+			}
+		}
+		channelz.AddTraceEvent(cc.channelzID, ted)
+		// TraceEvent needs to be called before RemoveEntry, as TraceEvent may add trace reference to
+		// the entity being deleted, and thus prevent it from being deleted right away.
 		channelz.RemoveEntry(cc.channelzID)
 	}
 	return nil
@@ -797,37 +937,45 @@ type addrConn struct {
 	cancel context.CancelFunc
 
 	cc     *ClientConn
-	addrs  []resolver.Address
 	dopts  dialOptions
-	events trace.EventLog
 	acbw   balancer.SubConn
+	scopts balancer.NewSubConnOptions
+
+	// transport is set when there's a viable transport (note: ac state may not be READY as LB channel
+	// health checking may require server to report healthy to set ac to READY), and is reset
+	// to nil when the current transport should no longer be used to create a stream (e.g. after GoAway
+	// is received, transport is closed, ac has been torn down).
+	transport transport.ClientTransport // The current transport.
+
+	mu      sync.Mutex
+	curAddr resolver.Address   // The current address.
+	addrs   []resolver.Address // All addresses that the resolver resolved to.
+
+	// Use updateConnectivityState for updating addrConn's connectivity state.
+	state connectivity.State
+
+	backoffIdx   int // Needs to be stateful for resetConnectBackoff.
+	resetBackoff chan struct{}
+
+	channelzID int64 // channelz unique identification number.
+	czData     *channelzData
+}
+
+// Note: this requires a lock on ac.mu.
+func (ac *addrConn) updateConnectivityState(s connectivity.State) {
+	if ac.state == s {
+		return
+	}
 
-	mu           sync.Mutex
-	curAddr      resolver.Address
-	reconnectIdx int // The index in addrs list to start reconnecting from.
-	state        connectivity.State
-	// ready is closed and becomes nil when a new transport is up or failed
-	// due to timeout.
-	ready     chan struct{}
-	transport transport.ClientTransport
-
-	// The reason this addrConn is torn down.
-	tearDownErr error
-
-	connectRetryNum int
-	// backoffDeadline is the time until which resetTransport needs to
-	// wait before increasing connectRetryNum count.
-	backoffDeadline time.Time
-	// connectDeadline is the time by which all connection
-	// negotiations must complete.
-	connectDeadline time.Time
-
-	channelzID          int64 // channelz unique identification number
-	czmu                sync.RWMutex
-	callsStarted        int64
-	callsSucceeded      int64
-	callsFailed         int64
-	lastCallStartedTime time.Time
+	updateMsg := fmt.Sprintf("Subchannel Connectivity change to %v", s)
+	ac.state = s
+	if channelz.IsOn() {
+		channelz.AddTraceEvent(ac.channelzID, &channelz.TraceEventDesc{
+			Desc:     updateMsg,
+			Severity: channelz.CtINFO,
+		})
+	}
+	ac.cc.handleSubConnStateChange(ac.acbw, s)
 }
 
 // adjustParams updates parameters used to create transports upon
@@ -844,289 +992,307 @@ func (ac *addrConn) adjustParams(r transport.GoAwayReason) {
 	}
 }
 
-// printf records an event in ac's event log, unless ac has been closed.
-// REQUIRES ac.mu is held.
-func (ac *addrConn) printf(format string, a ...interface{}) {
-	if ac.events != nil {
-		ac.events.Printf(format, a...)
-	}
-}
-
-// errorf records an error in ac's event log, unless ac has been closed.
-// REQUIRES ac.mu is held.
-func (ac *addrConn) errorf(format string, a ...interface{}) {
-	if ac.events != nil {
-		ac.events.Errorf(format, a...)
-	}
-}
+func (ac *addrConn) resetTransport() {
+	for i := 0; ; i++ {
+		if i > 0 {
+			ac.cc.resolveNow(resolver.ResolveNowOption{})
+		}
 
-// resetTransport recreates a transport to the address for ac.  The old
-// transport will close itself on error or when the clientconn is closed.
-// The created transport must receive initial settings frame from the server.
-// In case that doesn't happen, transportMonitor will kill the newly created
-// transport after connectDeadline has expired.
-// In case there was an error on the transport before the settings frame was
-// received, resetTransport resumes connecting to backends after the one that
-// was previously connected to. In case end of the list is reached, resetTransport
-// backs off until the original deadline.
-// If the DialOption WithWaitForHandshake was set, resetTrasport returns
-// successfully only after server settings are received.
-//
-// TODO(bar) make sure all state transitions are valid.
-func (ac *addrConn) resetTransport() error {
-	ac.mu.Lock()
-	if ac.state == connectivity.Shutdown {
-		ac.mu.Unlock()
-		return errConnClosing
-	}
-	if ac.ready != nil {
-		close(ac.ready)
-		ac.ready = nil
-	}
-	ac.transport = nil
-	ridx := ac.reconnectIdx
-	ac.mu.Unlock()
-	ac.cc.mu.RLock()
-	ac.dopts.copts.KeepaliveParams = ac.cc.mkp
-	ac.cc.mu.RUnlock()
-	var backoffDeadline, connectDeadline time.Time
-	for connectRetryNum := 0; ; connectRetryNum++ {
 		ac.mu.Lock()
-		if ac.backoffDeadline.IsZero() {
-			// This means either a successful HTTP2 connection was established
-			// or this is the first time this addrConn is trying to establish a
-			// connection.
-			backoffFor := ac.dopts.bs.Backoff(connectRetryNum) // time.Duration.
-			// This will be the duration that dial gets to finish.
-			dialDuration := getMinConnectTimeout()
-			if backoffFor > dialDuration {
-				// Give dial more time as we keep failing to connect.
-				dialDuration = backoffFor
-			}
-			start := time.Now()
-			backoffDeadline = start.Add(backoffFor)
-			connectDeadline = start.Add(dialDuration)
-			ridx = 0 // Start connecting from the beginning.
-		} else {
-			// Continue trying to connect with the same deadlines.
-			connectRetryNum = ac.connectRetryNum
-			backoffDeadline = ac.backoffDeadline
-			connectDeadline = ac.connectDeadline
-			ac.backoffDeadline = time.Time{}
-			ac.connectDeadline = time.Time{}
-			ac.connectRetryNum = 0
-		}
 		if ac.state == connectivity.Shutdown {
 			ac.mu.Unlock()
-			return errConnClosing
-		}
-		ac.printf("connecting")
-		if ac.state != connectivity.Connecting {
-			ac.state = connectivity.Connecting
-			ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
-		}
-		// copy ac.addrs in case of race
-		addrsIter := make([]resolver.Address, len(ac.addrs))
-		copy(addrsIter, ac.addrs)
-		copts := ac.dopts.copts
-		ac.mu.Unlock()
-		connected, err := ac.createTransport(connectRetryNum, ridx, backoffDeadline, connectDeadline, addrsIter, copts)
-		if err != nil {
-			return err
-		}
-		if connected {
-			return nil
+			return
 		}
-	}
-}
 
-// createTransport creates a connection to one of the backends in addrs.
-// It returns true if a connection was established.
-func (ac *addrConn) createTransport(connectRetryNum, ridx int, backoffDeadline, connectDeadline time.Time, addrs []resolver.Address, copts transport.ConnectOptions) (bool, error) {
-	for i := ridx; i < len(addrs); i++ {
-		addr := addrs[i]
-		target := transport.TargetInfo{
-			Addr:      addr.Addr,
-			Metadata:  addr.Metadata,
-			Authority: ac.cc.authority,
+		addrs := ac.addrs
+		backoffFor := ac.dopts.bs.Backoff(ac.backoffIdx)
+		// This will be the duration that dial gets to finish.
+		dialDuration := minConnectTimeout
+		if ac.dopts.minConnectTimeout != nil {
+			dialDuration = ac.dopts.minConnectTimeout()
 		}
-		done := make(chan struct{})
-		onPrefaceReceipt := func() {
-			ac.mu.Lock()
-			close(done)
-			if !ac.backoffDeadline.IsZero() {
-				// If we haven't already started reconnecting to
-				// other backends.
-				// Note, this can happen when writer notices an error
-				// and triggers resetTransport while at the same time
-				// reader receives the preface and invokes this closure.
-				ac.backoffDeadline = time.Time{}
-				ac.connectDeadline = time.Time{}
-				ac.connectRetryNum = 0
-			}
-			ac.mu.Unlock()
-		}
-		// Do not cancel in the success path because of
-		// this issue in Go1.6: https://github.com/golang/go/issues/15078.
-		connectCtx, cancel := context.WithDeadline(ac.ctx, connectDeadline)
-		if channelz.IsOn() {
-			copts.ChannelzParentID = ac.channelzID
+
+		if dialDuration < backoffFor {
+			// Give dial more time as we keep failing to connect.
+			dialDuration = backoffFor
 		}
-		newTr, err := transport.NewClientTransport(connectCtx, ac.cc.ctx, target, copts, onPrefaceReceipt)
+		// We can potentially spend all the time trying the first address, and
+		// if the server accepts the connection and then hangs, the following
+		// addresses will never be tried.
+		//
+		// The spec doesn't mention what should be done for multiple addresses.
+		// https://github.com/grpc/grpc/blob/master/doc/connection-backoff.md#proposed-backoff-algorithm
+		connectDeadline := time.Now().Add(dialDuration)
+
+		ac.updateConnectivityState(connectivity.Connecting)
+		ac.transport = nil
+		ac.mu.Unlock()
+
+		newTr, addr, reconnect, err := ac.tryAllAddrs(addrs, connectDeadline)
 		if err != nil {
-			cancel()
-			ac.cc.blockingpicker.updateConnectionError(err)
+			// After exhausting all addresses, the addrConn enters
+			// TRANSIENT_FAILURE.
 			ac.mu.Lock()
 			if ac.state == connectivity.Shutdown {
-				// ac.tearDown(...) has been invoked.
 				ac.mu.Unlock()
-				return false, errConnClosing
+				return
 			}
+			ac.updateConnectivityState(connectivity.TransientFailure)
+
+			// Backoff.
+			b := ac.resetBackoff
 			ac.mu.Unlock()
-			grpclog.Warningf("grpc: addrConn.createTransport failed to connect to %v. Err :%v. Reconnecting...", addr, err)
-			continue
-		}
-		if ac.dopts.waitForHandshake {
+
+			timer := time.NewTimer(backoffFor)
 			select {
-			case <-done:
-			case <-connectCtx.Done():
-				// Didn't receive server preface, must kill this new transport now.
-				grpclog.Warningf("grpc: addrConn.createTransport failed to receive server preface before deadline.")
-				newTr.Close()
-				continue
+			case <-timer.C:
+				ac.mu.Lock()
+				ac.backoffIdx++
+				ac.mu.Unlock()
+			case <-b:
+				timer.Stop()
 			case <-ac.ctx.Done():
+				timer.Stop()
+				return
 			}
+			continue
 		}
+
 		ac.mu.Lock()
 		if ac.state == connectivity.Shutdown {
 			ac.mu.Unlock()
-			// ac.tearDonn(...) has been invoked.
 			newTr.Close()
-			return false, errConnClosing
+			return
 		}
-		ac.printf("ready")
-		ac.state = connectivity.Ready
-		ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
-		ac.transport = newTr
 		ac.curAddr = addr
-		if ac.ready != nil {
-			close(ac.ready)
-			ac.ready = nil
+		ac.transport = newTr
+		ac.backoffIdx = 0
+
+		hctx, hcancel := context.WithCancel(ac.ctx)
+		ac.startHealthCheck(hctx)
+		ac.mu.Unlock()
+
+		// Block until the created transport is down. And when this happens,
+		// we restart from the top of the addr list.
+		<-reconnect.Done()
+		hcancel()
+		// restart connecting - the top of the loop will set state to
+		// CONNECTING.  This is against the current connectivity semantics doc,
+		// however it allows for graceful behavior for RPCs not yet dispatched
+		// - unfortunate timing would otherwise lead to the RPC failing even
+		// though the TRANSIENT_FAILURE state (called for by the doc) would be
+		// instantaneous.
+		//
+		// Ideally we should transition to Idle here and block until there is
+		// RPC activity that leads to the balancer requesting a reconnect of
+		// the associated SubConn.
+	}
+}
+
+// tryAllAddrs tries to creates a connection to the addresses, and stop when at the
+// first successful one. It returns the transport, the address and a Event in
+// the successful case. The Event fires when the returned transport disconnects.
+func (ac *addrConn) tryAllAddrs(addrs []resolver.Address, connectDeadline time.Time) (transport.ClientTransport, resolver.Address, *grpcsync.Event, error) {
+	for _, addr := range addrs {
+		ac.mu.Lock()
+		if ac.state == connectivity.Shutdown {
+			ac.mu.Unlock()
+			return nil, resolver.Address{}, nil, errConnClosing
 		}
-		select {
-		case <-done:
-			// If the server has responded back with preface already,
-			// don't set the reconnect parameters.
-		default:
-			ac.connectRetryNum = connectRetryNum
-			ac.backoffDeadline = backoffDeadline
-			ac.connectDeadline = connectDeadline
-			ac.reconnectIdx = i + 1 // Start reconnecting from the next backend in the list.
+
+		ac.cc.mu.RLock()
+		ac.dopts.copts.KeepaliveParams = ac.cc.mkp
+		ac.cc.mu.RUnlock()
+
+		copts := ac.dopts.copts
+		if ac.scopts.CredsBundle != nil {
+			copts.CredsBundle = ac.scopts.CredsBundle
 		}
 		ac.mu.Unlock()
-		return true, nil
+
+		if channelz.IsOn() {
+			channelz.AddTraceEvent(ac.channelzID, &channelz.TraceEventDesc{
+				Desc:     fmt.Sprintf("Subchannel picks a new address %q to connect", addr.Addr),
+				Severity: channelz.CtINFO,
+			})
+		}
+
+		newTr, reconnect, err := ac.createTransport(addr, copts, connectDeadline)
+		if err == nil {
+			return newTr, addr, reconnect, nil
+		}
+		ac.cc.blockingpicker.updateConnectionError(err)
 	}
-	ac.mu.Lock()
-	if ac.state == connectivity.Shutdown {
+
+	// Couldn't connect to any address.
+	return nil, resolver.Address{}, nil, fmt.Errorf("couldn't connect to any address")
+}
+
+// createTransport creates a connection to addr. It returns the transport and a
+// Event in the successful case. The Event fires when the returned transport
+// disconnects.
+func (ac *addrConn) createTransport(addr resolver.Address, copts transport.ConnectOptions, connectDeadline time.Time) (transport.ClientTransport, *grpcsync.Event, error) {
+	prefaceReceived := make(chan struct{})
+	onCloseCalled := make(chan struct{})
+	reconnect := grpcsync.NewEvent()
+
+	target := transport.TargetInfo{
+		Addr:      addr.Addr,
+		Metadata:  addr.Metadata,
+		Authority: ac.cc.authority,
+	}
+
+	once := sync.Once{}
+	onGoAway := func(r transport.GoAwayReason) {
+		ac.mu.Lock()
+		ac.adjustParams(r)
+		once.Do(func() {
+			if ac.state == connectivity.Ready {
+				// Prevent this SubConn from being used for new RPCs by setting its
+				// state to Connecting.
+				//
+				// TODO: this should be Idle when grpc-go properly supports it.
+				ac.updateConnectivityState(connectivity.Connecting)
+			}
+		})
 		ac.mu.Unlock()
-		return false, errConnClosing
+		reconnect.Fire()
 	}
-	ac.state = connectivity.TransientFailure
-	ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
-	ac.cc.resolveNow(resolver.ResolveNowOption{})
-	if ac.ready != nil {
-		close(ac.ready)
-		ac.ready = nil
+
+	onClose := func() {
+		ac.mu.Lock()
+		once.Do(func() {
+			if ac.state == connectivity.Ready {
+				// Prevent this SubConn from being used for new RPCs by setting its
+				// state to Connecting.
+				//
+				// TODO: this should be Idle when grpc-go properly supports it.
+				ac.updateConnectivityState(connectivity.Connecting)
+			}
+		})
+		ac.mu.Unlock()
+		close(onCloseCalled)
+		reconnect.Fire()
 	}
-	ac.mu.Unlock()
-	timer := time.NewTimer(backoffDeadline.Sub(time.Now()))
-	select {
-	case <-timer.C:
-	case <-ac.ctx.Done():
-		timer.Stop()
-		return false, ac.ctx.Err()
+
+	onPrefaceReceipt := func() {
+		close(prefaceReceived)
 	}
-	return false, nil
+
+	connectCtx, cancel := context.WithDeadline(ac.ctx, connectDeadline)
+	defer cancel()
+	if channelz.IsOn() {
+		copts.ChannelzParentID = ac.channelzID
+	}
+
+	newTr, err := transport.NewClientTransport(connectCtx, ac.cc.ctx, target, copts, onPrefaceReceipt, onGoAway, onClose)
+	if err != nil {
+		// newTr is either nil, or closed.
+		grpclog.Warningf("grpc: addrConn.createTransport failed to connect to %v. Err :%v. Reconnecting...", addr, err)
+		return nil, nil, err
+	}
+
+	select {
+	case <-time.After(connectDeadline.Sub(time.Now())):
+		// We didn't get the preface in time.
+		newTr.Close()
+		grpclog.Warningf("grpc: addrConn.createTransport failed to connect to %v: didn't receive server preface in time. Reconnecting...", addr)
+		return nil, nil, errors.New("timed out waiting for server handshake")
+	case <-prefaceReceived:
+		// We got the preface - huzzah! things are good.
+	case <-onCloseCalled:
+		// The transport has already closed - noop.
+		return nil, nil, errors.New("connection closed")
+		// TODO(deklerk) this should bail on ac.ctx.Done(). Add a test and fix.
+	}
+	return newTr, reconnect, nil
 }
 
-// Run in a goroutine to track the error in transport and create the
-// new transport if an error happens. It returns when the channel is closing.
-func (ac *addrConn) transportMonitor() {
-	for {
-		var timer *time.Timer
-		var cdeadline <-chan time.Time
-		ac.mu.Lock()
-		t := ac.transport
-		if !ac.connectDeadline.IsZero() {
-			timer = time.NewTimer(ac.connectDeadline.Sub(time.Now()))
-			cdeadline = timer.C
-		}
-		ac.mu.Unlock()
-		// Block until we receive a goaway or an error occurs.
-		select {
-		case <-t.GoAway():
-			done := t.Error()
-			cleanup := t.Close
-			// Since this transport will be orphaned (won't have a transportMonitor)
-			// we need to launch a goroutine to keep track of clientConn.Close()
-			// happening since it might not be noticed by any other goroutine for a while.
-			go func() {
-				<-done
-				cleanup()
-			}()
-		case <-t.Error():
-			// In case this is triggered because clientConn.Close()
-			// was called, we want to immeditately close the transport
-			// since no other goroutine might notice it for a while.
-			t.Close()
-		case <-cdeadline:
-			ac.mu.Lock()
-			// This implies that client received server preface.
-			if ac.backoffDeadline.IsZero() {
-				ac.mu.Unlock()
-				continue
-			}
-			ac.mu.Unlock()
-			timer = nil
-			// No server preface received until deadline.
-			// Kill the connection.
-			grpclog.Warningf("grpc: addrConn.transportMonitor didn't get server preface after waiting. Closing the new transport now.")
-			t.Close()
-		}
-		if timer != nil {
-			timer.Stop()
-		}
-		// If a GoAway happened, regardless of error, adjust our keepalive
-		// parameters as appropriate.
-		select {
-		case <-t.GoAway():
-			ac.adjustParams(t.GetGoAwayReason())
-		default:
+// startHealthCheck starts the health checking stream (RPC) to watch the health
+// stats of this connection if health checking is requested and configured.
+//
+// LB channel health checking is enabled when all requirements below are met:
+// 1. it is not disabled by the user with the WithDisableHealthCheck DialOption
+// 2. internal.HealthCheckFunc is set by importing the grpc/healthcheck package
+// 3. a service config with non-empty healthCheckConfig field is provided
+// 4. the load balancer requests it
+//
+// It sets addrConn to READY if the health checking stream is not started.
+//
+// Caller must hold ac.mu.
+func (ac *addrConn) startHealthCheck(ctx context.Context) {
+	var healthcheckManagingState bool
+	defer func() {
+		if !healthcheckManagingState {
+			ac.updateConnectivityState(connectivity.Ready)
 		}
+	}()
+
+	if ac.cc.dopts.disableHealthCheck {
+		return
+	}
+	healthCheckConfig := ac.cc.healthCheckConfig()
+	if healthCheckConfig == nil {
+		return
+	}
+	if !ac.scopts.HealthCheckEnabled {
+		return
+	}
+	healthCheckFunc := ac.cc.dopts.healthCheckFunc
+	if healthCheckFunc == nil {
+		// The health package is not imported to set health check function.
+		//
+		// TODO: add a link to the health check doc in the error message.
+		grpclog.Error("Health check is requested but health check function is not set.")
+		return
+	}
+
+	healthcheckManagingState = true
+
+	// Set up the health check helper functions.
+	currentTr := ac.transport
+	newStream := func(method string) (interface{}, error) {
 		ac.mu.Lock()
-		if ac.state == connectivity.Shutdown {
+		if ac.transport != currentTr {
 			ac.mu.Unlock()
-			return
+			return nil, status.Error(codes.Canceled, "the provided transport is no longer valid to use")
 		}
-		// Set connectivity state to TransientFailure before calling
-		// resetTransport. Transition READY->CONNECTING is not valid.
-		ac.state = connectivity.TransientFailure
-		ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
-		ac.cc.resolveNow(resolver.ResolveNowOption{})
-		ac.curAddr = resolver.Address{}
 		ac.mu.Unlock()
-		if err := ac.resetTransport(); err != nil {
-			ac.mu.Lock()
-			ac.printf("transport exiting: %v", err)
-			ac.mu.Unlock()
-			grpclog.Warningf("grpc: addrConn.transportMonitor exits due to: %v", err)
-			if err != errConnClosing {
-				// Keep this ac in cc.conns, to get the reason it's torn down.
-				ac.tearDown(err)
-			}
+		return newNonRetryClientStream(ctx, &StreamDesc{ServerStreams: true}, method, currentTr, ac)
+	}
+	setConnectivityState := func(s connectivity.State) {
+		ac.mu.Lock()
+		defer ac.mu.Unlock()
+		if ac.transport != currentTr {
 			return
 		}
+		ac.updateConnectivityState(s)
 	}
+	// Start the health checking stream.
+	go func() {
+		err := ac.cc.dopts.healthCheckFunc(ctx, newStream, setConnectivityState, healthCheckConfig.ServiceName)
+		if err != nil {
+			if status.Code(err) == codes.Unimplemented {
+				if channelz.IsOn() {
+					channelz.AddTraceEvent(ac.channelzID, &channelz.TraceEventDesc{
+						Desc:     "Subchannel health check is unimplemented at server side, thus health check is disabled",
+						Severity: channelz.CtError,
+					})
+				}
+				grpclog.Error("Subchannel health check is unimplemented at server side, thus health check is disabled")
+			} else {
+				grpclog.Errorf("HealthCheckFunc exits with unexpected error %v", err)
+			}
+		}
+	}()
+}
+
+func (ac *addrConn) resetConnectBackoff() {
+	ac.mu.Lock()
+	close(ac.resetBackoff)
+	ac.backoffIdx = 0
+	ac.resetBackoff = make(chan struct{})
+	ac.mu.Unlock()
 }
 
 // getReadyTransport returns the transport if ac's state is READY.
@@ -1134,7 +1300,7 @@ func (ac *addrConn) transportMonitor() {
 // If ac's state is IDLE, it will trigger ac to connect.
 func (ac *addrConn) getReadyTransport() (transport.ClientTransport, bool) {
 	ac.mu.Lock()
-	if ac.state == connectivity.Ready {
+	if ac.state == connectivity.Ready && ac.transport != nil {
 		t := ac.transport
 		ac.mu.Unlock()
 		return t, true
@@ -1157,34 +1323,42 @@ func (ac *addrConn) getReadyTransport() (transport.ClientTransport, bool) {
 // tight loop.
 // tearDown doesn't remove ac from ac.cc.conns.
 func (ac *addrConn) tearDown(err error) {
-	ac.cancel()
 	ac.mu.Lock()
-	defer ac.mu.Unlock()
 	if ac.state == connectivity.Shutdown {
+		ac.mu.Unlock()
 		return
 	}
+	curTr := ac.transport
+	ac.transport = nil
+	// We have to set the state to Shutdown before anything else to prevent races
+	// between setting the state and logic that waits on context cancelation / etc.
+	ac.updateConnectivityState(connectivity.Shutdown)
+	ac.cancel()
 	ac.curAddr = resolver.Address{}
-	if err == errConnDrain && ac.transport != nil {
+	if err == errConnDrain && curTr != nil {
 		// GracefulClose(...) may be executed multiple times when
 		// i) receiving multiple GoAway frames from the server; or
 		// ii) there are concurrent name resolver/Balancer triggered
 		// address removal and GoAway.
-		ac.transport.GracefulClose()
-	}
-	ac.state = connectivity.Shutdown
-	ac.tearDownErr = err
-	ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
-	if ac.events != nil {
-		ac.events.Finish()
-		ac.events = nil
-	}
-	if ac.ready != nil {
-		close(ac.ready)
-		ac.ready = nil
+		// We have to unlock and re-lock here because GracefulClose => Close => onClose, which requires locking ac.mu.
+		ac.mu.Unlock()
+		curTr.GracefulClose()
+		ac.mu.Lock()
 	}
 	if channelz.IsOn() {
+		channelz.AddTraceEvent(ac.channelzID, &channelz.TraceEventDesc{
+			Desc:     "Subchannel Deleted",
+			Severity: channelz.CtINFO,
+			Parent: &channelz.TraceEventDesc{
+				Desc:     fmt.Sprintf("Subchanel(id:%d) deleted", ac.channelzID),
+				Severity: channelz.CtINFO,
+			},
+		})
+		// TraceEvent needs to be called before RemoveEntry, as TraceEvent may add trace reference to
+		// the entity beng deleted, and thus prevent it from being deleted right away.
 		channelz.RemoveEntry(ac.channelzID)
 	}
+	ac.mu.Unlock()
 }
 
 func (ac *addrConn) getState() connectivity.State {
@@ -1197,36 +1371,27 @@ func (ac *addrConn) ChannelzMetric() *channelz.ChannelInternalMetric {
 	ac.mu.Lock()
 	addr := ac.curAddr.Addr
 	ac.mu.Unlock()
-	state := ac.getState()
-	ac.czmu.RLock()
-	defer ac.czmu.RUnlock()
 	return &channelz.ChannelInternalMetric{
-		State:                    state,
+		State:                    ac.getState(),
 		Target:                   addr,
-		CallsStarted:             ac.callsStarted,
-		CallsSucceeded:           ac.callsSucceeded,
-		CallsFailed:              ac.callsFailed,
-		LastCallStartedTimestamp: ac.lastCallStartedTime,
+		CallsStarted:             atomic.LoadInt64(&ac.czData.callsStarted),
+		CallsSucceeded:           atomic.LoadInt64(&ac.czData.callsSucceeded),
+		CallsFailed:              atomic.LoadInt64(&ac.czData.callsFailed),
+		LastCallStartedTimestamp: time.Unix(0, atomic.LoadInt64(&ac.czData.lastCallStartedTime)),
 	}
 }
 
 func (ac *addrConn) incrCallsStarted() {
-	ac.czmu.Lock()
-	ac.callsStarted++
-	ac.lastCallStartedTime = time.Now()
-	ac.czmu.Unlock()
+	atomic.AddInt64(&ac.czData.callsStarted, 1)
+	atomic.StoreInt64(&ac.czData.lastCallStartedTime, time.Now().UnixNano())
 }
 
 func (ac *addrConn) incrCallsSucceeded() {
-	ac.czmu.Lock()
-	ac.callsSucceeded++
-	ac.czmu.Unlock()
+	atomic.AddInt64(&ac.czData.callsSucceeded, 1)
 }
 
 func (ac *addrConn) incrCallsFailed() {
-	ac.czmu.Lock()
-	ac.callsFailed++
-	ac.czmu.Unlock()
+	atomic.AddInt64(&ac.czData.callsFailed, 1)
 }
 
 type retryThrottler struct {
@@ -1266,6 +1431,14 @@ func (rt *retryThrottler) successfulRPC() {
 	}
 }
 
+type channelzChannel struct {
+	cc *ClientConn
+}
+
+func (c *channelzChannel) ChannelzMetric() *channelz.ChannelInternalMetric {
+	return c.cc.channelzMetric()
+}
+
 // ErrClientConnTimeout indicates that the ClientConn cannot establish the
 // underlying connections within the specified timeout.
 //
diff --git a/vendor/google.golang.org/grpc/codes/codes.go b/vendor/google.golang.org/grpc/codes/codes.go
index d9b9d578..02738839 100644
--- a/vendor/google.golang.org/grpc/codes/codes.go
+++ b/vendor/google.golang.org/grpc/codes/codes.go
@@ -132,7 +132,8 @@ const (
 
 	// Unavailable indicates the service is currently unavailable.
 	// This is a most likely a transient condition and may be corrected
-	// by retrying with a backoff.
+	// by retrying with a backoff. Note that it is not always safe to retry
+	// non-idempotent operations.
 	//
 	// See litmus test above for deciding between FailedPrecondition,
 	// Aborted, and Unavailable.
diff --git a/vendor/google.golang.org/grpc/connectivity/connectivity.go b/vendor/google.golang.org/grpc/connectivity/connectivity.go
index 568ef5dc..34ec36fb 100644
--- a/vendor/google.golang.org/grpc/connectivity/connectivity.go
+++ b/vendor/google.golang.org/grpc/connectivity/connectivity.go
@@ -22,7 +22,8 @@
 package connectivity
 
 import (
-	"golang.org/x/net/context"
+	"context"
+
 	"google.golang.org/grpc/grpclog"
 )
 
@@ -51,7 +52,7 @@ func (s State) String() string {
 const (
 	// Idle indicates the ClientConn is idle.
 	Idle State = iota
-	// Connecting indicates the ClienConn is connecting.
+	// Connecting indicates the ClientConn is connecting.
 	Connecting
 	// Ready indicates the ClientConn is ready for work.
 	Ready
diff --git a/vendor/google.golang.org/grpc/credentials/credentials.go b/vendor/google.golang.org/grpc/credentials/credentials.go
index 1dae57ab..8ea3d4a1 100644
--- a/vendor/google.golang.org/grpc/credentials/credentials.go
+++ b/vendor/google.golang.org/grpc/credentials/credentials.go
@@ -23,6 +23,7 @@
 package credentials // import "google.golang.org/grpc/credentials"
 
 import (
+	"context"
 	"crypto/tls"
 	"crypto/x509"
 	"errors"
@@ -32,12 +33,9 @@ import (
 	"strings"
 
 	"github.com/golang/protobuf/proto"
-	"golang.org/x/net/context"
+	"google.golang.org/grpc/credentials/internal"
 )
 
-// alpnProtoStr are the specified application level protocols for gRPC.
-var alpnProtoStr = []string{"h2"}
-
 // PerRPCCredentials defines the common interface for the credentials which need to
 // attach security information to every RPC (e.g., oauth2).
 type PerRPCCredentials interface {
@@ -108,6 +106,25 @@ type TransportCredentials interface {
 	OverrideServerName(string) error
 }
 
+// Bundle is a combination of TransportCredentials and PerRPCCredentials.
+//
+// It also contains a mode switching method, so it can be used as a combination
+// of different credential policies.
+//
+// Bundle cannot be used together with individual TransportCredentials.
+// PerRPCCredentials from Bundle will be appended to other PerRPCCredentials.
+//
+// This API is experimental.
+type Bundle interface {
+	TransportCredentials() TransportCredentials
+	PerRPCCredentials() PerRPCCredentials
+	// NewWithMode should make a copy of Bundle, and switch mode. Modifying the
+	// existing Bundle may cause races.
+	//
+	// NewWithMode returns nil if the requested mode is not supported.
+	NewWithMode(mode string) (Bundle, error)
+}
+
 // TLSInfo contains the auth information for a TLS authenticated connection.
 // It implements the AuthInfo interface.
 type TLSInfo struct {
@@ -119,8 +136,8 @@ func (t TLSInfo) AuthType() string {
 	return "tls"
 }
 
-// GetChannelzSecurityValue returns security info requested by channelz.
-func (t TLSInfo) GetChannelzSecurityValue() ChannelzSecurityValue {
+// GetSecurityValue returns security info requested by channelz.
+func (t TLSInfo) GetSecurityValue() ChannelzSecurityValue {
 	v := &TLSChannelzSecurityValue{
 		StandardName: cipherSuiteLookup[t.State.CipherSuite],
 	}
@@ -168,7 +185,7 @@ func (c *tlsCreds) ClientHandshake(ctx context.Context, authority string, rawCon
 	case <-ctx.Done():
 		return nil, nil, ctx.Err()
 	}
-	return tlsConn{Conn: conn, rawConn: rawConn}, TLSInfo{conn.ConnectionState()}, nil
+	return internal.WrapSyscallConn(rawConn, conn), TLSInfo{conn.ConnectionState()}, nil
 }
 
 func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error) {
@@ -176,7 +193,7 @@ func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error)
 	if err := conn.Handshake(); err != nil {
 		return nil, nil, err
 	}
-	return tlsConn{Conn: conn, rawConn: rawConn}, TLSInfo{conn.ConnectionState()}, nil
+	return internal.WrapSyscallConn(rawConn, conn), TLSInfo{conn.ConnectionState()}, nil
 }
 
 func (c *tlsCreds) Clone() TransportCredentials {
@@ -188,10 +205,23 @@ func (c *tlsCreds) OverrideServerName(serverNameOverride string) error {
 	return nil
 }
 
+const alpnProtoStrH2 = "h2"
+
+func appendH2ToNextProtos(ps []string) []string {
+	for _, p := range ps {
+		if p == alpnProtoStrH2 {
+			return ps
+		}
+	}
+	ret := make([]string, 0, len(ps)+1)
+	ret = append(ret, ps...)
+	return append(ret, alpnProtoStrH2)
+}
+
 // NewTLS uses c to construct a TransportCredentials based on TLS.
 func NewTLS(c *tls.Config) TransportCredentials {
 	tc := &tlsCreds{cloneTLSConfig(c)}
-	tc.config.NextProtos = alpnProtoStr
+	tc.config.NextProtos = appendH2ToNextProtos(tc.config.NextProtos)
 	return tc
 }
 
@@ -248,29 +278,22 @@ type ChannelzSecurityValue interface {
 // TLSChannelzSecurityValue defines the struct that TLS protocol should return
 // from GetSecurityValue(), containing security info like cipher and certificate used.
 type TLSChannelzSecurityValue struct {
+	ChannelzSecurityValue
 	StandardName      string
 	LocalCertificate  []byte
 	RemoteCertificate []byte
 }
 
-func (*TLSChannelzSecurityValue) isChannelzSecurityValue() {}
-
 // OtherChannelzSecurityValue defines the struct that non-TLS protocol should return
 // from GetSecurityValue(), which contains protocol specific security info. Note
 // the Value field will be sent to users of channelz requesting channel info, and
 // thus sensitive info should better be avoided.
 type OtherChannelzSecurityValue struct {
+	ChannelzSecurityValue
 	Name  string
 	Value proto.Message
 }
 
-func (*OtherChannelzSecurityValue) isChannelzSecurityValue() {}
-
-type tlsConn struct {
-	*tls.Conn
-	rawConn net.Conn
-}
-
 var cipherSuiteLookup = map[uint16]string{
 	tls.TLS_RSA_WITH_RC4_128_SHA:                "TLS_RSA_WITH_RC4_128_SHA",
 	tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA:           "TLS_RSA_WITH_3DES_EDE_CBC_SHA",
@@ -290,4 +313,24 @@ var cipherSuiteLookup = map[uint16]string{
 	tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384:   "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384",
 	tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384: "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
 	tls.TLS_FALLBACK_SCSV:                       "TLS_FALLBACK_SCSV",
+	tls.TLS_RSA_WITH_AES_128_CBC_SHA256:         "TLS_RSA_WITH_AES_128_CBC_SHA256",
+	tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256: "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256",
+	tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256:   "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256",
+	tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305:    "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305",
+	tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305:  "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305",
+}
+
+// cloneTLSConfig returns a shallow clone of the exported
+// fields of cfg, ignoring the unexported sync.Once, which
+// contains a mutex and must not be copied.
+//
+// If cfg is nil, a new zero tls.Config is returned.
+//
+// TODO: inline this function if possible.
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+
+	return cfg.Clone()
 }
diff --git a/vendor/google.golang.org/grpc/credentials/go16.go b/vendor/google.golang.org/grpc/credentials/go16.go
deleted file mode 100644
index d6bbcc9f..00000000
--- a/vendor/google.golang.org/grpc/credentials/go16.go
+++ /dev/null
@@ -1,57 +0,0 @@
-// +build !go1.7
-
-/*
- *
- * Copyright 2016 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package credentials
-
-import (
-	"crypto/tls"
-)
-
-// cloneTLSConfig returns a shallow clone of the exported
-// fields of cfg, ignoring the unexported sync.Once, which
-// contains a mutex and must not be copied.
-//
-// If cfg is nil, a new zero tls.Config is returned.
-func cloneTLSConfig(cfg *tls.Config) *tls.Config {
-	if cfg == nil {
-		return &tls.Config{}
-	}
-	return &tls.Config{
-		Rand:                     cfg.Rand,
-		Time:                     cfg.Time,
-		Certificates:             cfg.Certificates,
-		NameToCertificate:        cfg.NameToCertificate,
-		GetCertificate:           cfg.GetCertificate,
-		RootCAs:                  cfg.RootCAs,
-		NextProtos:               cfg.NextProtos,
-		ServerName:               cfg.ServerName,
-		ClientAuth:               cfg.ClientAuth,
-		ClientCAs:                cfg.ClientCAs,
-		InsecureSkipVerify:       cfg.InsecureSkipVerify,
-		CipherSuites:             cfg.CipherSuites,
-		PreferServerCipherSuites: cfg.PreferServerCipherSuites,
-		SessionTicketsDisabled:   cfg.SessionTicketsDisabled,
-		SessionTicketKey:         cfg.SessionTicketKey,
-		ClientSessionCache:       cfg.ClientSessionCache,
-		MinVersion:               cfg.MinVersion,
-		MaxVersion:               cfg.MaxVersion,
-		CurvePreferences:         cfg.CurvePreferences,
-	}
-}
diff --git a/vendor/google.golang.org/grpc/credentials/go17.go b/vendor/google.golang.org/grpc/credentials/go17.go
deleted file mode 100644
index fbd50000..00000000
--- a/vendor/google.golang.org/grpc/credentials/go17.go
+++ /dev/null
@@ -1,59 +0,0 @@
-// +build go1.7,!go1.8
-
-/*
- *
- * Copyright 2016 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package credentials
-
-import (
-	"crypto/tls"
-)
-
-// cloneTLSConfig returns a shallow clone of the exported
-// fields of cfg, ignoring the unexported sync.Once, which
-// contains a mutex and must not be copied.
-//
-// If cfg is nil, a new zero tls.Config is returned.
-func cloneTLSConfig(cfg *tls.Config) *tls.Config {
-	if cfg == nil {
-		return &tls.Config{}
-	}
-	return &tls.Config{
-		Rand:                        cfg.Rand,
-		Time:                        cfg.Time,
-		Certificates:                cfg.Certificates,
-		NameToCertificate:           cfg.NameToCertificate,
-		GetCertificate:              cfg.GetCertificate,
-		RootCAs:                     cfg.RootCAs,
-		NextProtos:                  cfg.NextProtos,
-		ServerName:                  cfg.ServerName,
-		ClientAuth:                  cfg.ClientAuth,
-		ClientCAs:                   cfg.ClientCAs,
-		InsecureSkipVerify:          cfg.InsecureSkipVerify,
-		CipherSuites:                cfg.CipherSuites,
-		PreferServerCipherSuites:    cfg.PreferServerCipherSuites,
-		SessionTicketsDisabled:      cfg.SessionTicketsDisabled,
-		SessionTicketKey:            cfg.SessionTicketKey,
-		ClientSessionCache:          cfg.ClientSessionCache,
-		MinVersion:                  cfg.MinVersion,
-		MaxVersion:                  cfg.MaxVersion,
-		CurvePreferences:            cfg.CurvePreferences,
-		DynamicRecordSizingDisabled: cfg.DynamicRecordSizingDisabled,
-		Renegotiation:               cfg.Renegotiation,
-	}
-}
diff --git a/vendor/google.golang.org/grpc/credentials/go18.go b/vendor/google.golang.org/grpc/credentials/go18.go
deleted file mode 100644
index db30d46c..00000000
--- a/vendor/google.golang.org/grpc/credentials/go18.go
+++ /dev/null
@@ -1,46 +0,0 @@
-// +build go1.8
-
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package credentials
-
-import (
-	"crypto/tls"
-)
-
-func init() {
-	cipherSuiteLookup[tls.TLS_RSA_WITH_AES_128_CBC_SHA256] = "TLS_RSA_WITH_AES_128_CBC_SHA256"
-	cipherSuiteLookup[tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256] = "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256"
-	cipherSuiteLookup[tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256] = "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256"
-	cipherSuiteLookup[tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305] = "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305"
-	cipherSuiteLookup[tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305] = "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305"
-}
-
-// cloneTLSConfig returns a shallow clone of the exported
-// fields of cfg, ignoring the unexported sync.Once, which
-// contains a mutex and must not be copied.
-//
-// If cfg is nil, a new zero tls.Config is returned.
-func cloneTLSConfig(cfg *tls.Config) *tls.Config {
-	if cfg == nil {
-		return &tls.Config{}
-	}
-
-	return cfg.Clone()
-}
diff --git a/vendor/google.golang.org/grpc/credentials/internal/syscallconn.go b/vendor/google.golang.org/grpc/credentials/internal/syscallconn.go
new file mode 100644
index 00000000..2f4472be
--- /dev/null
+++ b/vendor/google.golang.org/grpc/credentials/internal/syscallconn.go
@@ -0,0 +1,61 @@
+// +build !appengine
+
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package internal contains credentials-internal code.
+package internal
+
+import (
+	"net"
+	"syscall"
+)
+
+type sysConn = syscall.Conn
+
+// syscallConn keeps reference of rawConn to support syscall.Conn for channelz.
+// SyscallConn() (the method in interface syscall.Conn) is explicitly
+// implemented on this type,
+//
+// Interface syscall.Conn is implemented by most net.Conn implementations (e.g.
+// TCPConn, UnixConn), but is not part of net.Conn interface. So wrapper conns
+// that embed net.Conn don't implement syscall.Conn. (Side note: tls.Conn
+// doesn't embed net.Conn, so even if syscall.Conn is part of net.Conn, it won't
+// help here).
+type syscallConn struct {
+	net.Conn
+	// sysConn is a type alias of syscall.Conn. It's necessary because the name
+	// `Conn` collides with `net.Conn`.
+	sysConn
+}
+
+// WrapSyscallConn tries to wrap rawConn and newConn into a net.Conn that
+// implements syscall.Conn. rawConn will be used to support syscall, and newConn
+// will be used for read/write.
+//
+// This function returns newConn if rawConn doesn't implement syscall.Conn.
+func WrapSyscallConn(rawConn, newConn net.Conn) net.Conn {
+	sysConn, ok := rawConn.(syscall.Conn)
+	if !ok {
+		return newConn
+	}
+	return &syscallConn{
+		Conn:    newConn,
+		sysConn: sysConn,
+	}
+}
diff --git a/vendor/google.golang.org/grpc/naming/go18.go b/vendor/google.golang.org/grpc/credentials/internal/syscallconn_appengine.go
similarity index 73%
rename from vendor/google.golang.org/grpc/naming/go18.go
rename to vendor/google.golang.org/grpc/credentials/internal/syscallconn_appengine.go
index b5a0f842..d4346e9e 100644
--- a/vendor/google.golang.org/grpc/naming/go18.go
+++ b/vendor/google.golang.org/grpc/credentials/internal/syscallconn_appengine.go
@@ -1,8 +1,8 @@
-// +build go1.8
+// +build appengine
 
 /*
  *
- * Copyright 2017 gRPC authors.
+ * Copyright 2018 gRPC authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,11 +18,13 @@
  *
  */
 
-package naming
+package internal
 
-import "net"
-
-var (
-	lookupHost = net.DefaultResolver.LookupHost
-	lookupSRV  = net.DefaultResolver.LookupSRV
+import (
+	"net"
 )
+
+// WrapSyscallConn returns newConn on appengine.
+func WrapSyscallConn(rawConn, newConn net.Conn) net.Conn {
+	return newConn
+}
diff --git a/vendor/google.golang.org/grpc/credentials/go19.go b/vendor/google.golang.org/grpc/credentials/tls13.go
similarity index 60%
rename from vendor/google.golang.org/grpc/credentials/go19.go
rename to vendor/google.golang.org/grpc/credentials/tls13.go
index 2a4ca1a5..ccbf35b3 100644
--- a/vendor/google.golang.org/grpc/credentials/go19.go
+++ b/vendor/google.golang.org/grpc/credentials/tls13.go
@@ -1,8 +1,8 @@
-// +build go1.9,!appengine
+// +build go1.12
 
 /*
  *
- * Copyright 2018 gRPC authors.
+ * Copyright 2019 gRPC authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,16 +20,11 @@
 
 package credentials
 
-import (
-	"errors"
-	"syscall"
-)
+import "crypto/tls"
 
-// implements the syscall.Conn interface
-func (c tlsConn) SyscallConn() (syscall.RawConn, error) {
-	conn, ok := c.rawConn.(syscall.Conn)
-	if !ok {
-		return nil, errors.New("RawConn does not implement syscall.Conn")
-	}
-	return conn.SyscallConn()
+// This init function adds cipher suite constants only defined in Go 1.12.
+func init() {
+	cipherSuiteLookup[tls.TLS_AES_128_GCM_SHA256] = "TLS_AES_128_GCM_SHA256"
+	cipherSuiteLookup[tls.TLS_AES_256_GCM_SHA384] = "TLS_AES_256_GCM_SHA384"
+	cipherSuiteLookup[tls.TLS_CHACHA20_POLY1305_SHA256] = "TLS_CHACHA20_POLY1305_SHA256"
 }
diff --git a/vendor/google.golang.org/grpc/dialoptions.go b/vendor/google.golang.org/grpc/dialoptions.go
index 20accf1a..e8f34d0d 100644
--- a/vendor/google.golang.org/grpc/dialoptions.go
+++ b/vendor/google.golang.org/grpc/dialoptions.go
@@ -19,13 +19,14 @@
 package grpc
 
 import (
+	"context"
 	"fmt"
 	"net"
 	"time"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/balancer"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal"
 	"google.golang.org/grpc/internal/backoff"
 	"google.golang.org/grpc/internal/envconfig"
@@ -38,8 +39,12 @@ import (
 // dialOptions configure a Dial call. dialOptions are set by the DialOption
 // values passed to Dial.
 type dialOptions struct {
-	unaryInt    UnaryClientInterceptor
-	streamInt   StreamClientInterceptor
+	unaryInt  UnaryClientInterceptor
+	streamInt StreamClientInterceptor
+
+	chainUnaryInts  []UnaryClientInterceptor
+	chainStreamInts []StreamClientInterceptor
+
 	cp          Compressor
 	dc          Decompressor
 	bs          backoff.Strategy
@@ -54,11 +59,15 @@ type dialOptions struct {
 	// balancer, and also by WithBalancerName dial option.
 	balancerBuilder balancer.Builder
 	// This is to support grpclb.
-	resolverBuilder      resolver.Builder
-	waitForHandshake     bool
-	channelzParentID     int64
-	disableServiceConfig bool
-	disableRetry         bool
+	resolverBuilder             resolver.Builder
+	channelzParentID            int64
+	disableServiceConfig        bool
+	disableRetry                bool
+	disableHealthCheck          bool
+	healthCheckFunc             internal.HealthChecker
+	minConnectTimeout           func() time.Duration
+	defaultServiceConfig        *ServiceConfig // defaultServiceConfig is parsed from defaultServiceConfigRawJSON.
+	defaultServiceConfigRawJSON *string
 }
 
 // DialOption configures how we set up the connection.
@@ -90,14 +99,6 @@ func newFuncDialOption(f func(*dialOptions)) *funcDialOption {
 	}
 }
 
-// WithWaitForHandshake blocks until the initial settings frame is received from
-// the server before assigning RPCs to the connection. Experimental API.
-func WithWaitForHandshake() DialOption {
-	return newFuncDialOption(func(o *dialOptions) {
-		o.waitForHandshake = true
-	})
-}
-
 // WithWriteBufferSize determines how much data can be batched before doing a
 // write on the wire. The corresponding memory allocation for this buffer will
 // be twice the size to keep syscalls low. The default value for this buffer is
@@ -143,7 +144,8 @@ func WithInitialConnWindowSize(s int32) DialOption {
 // WithMaxMsgSize returns a DialOption which sets the maximum message size the
 // client can receive.
 //
-// Deprecated: use WithDefaultCallOptions(MaxCallRecvMsgSize(s)) instead.
+// Deprecated: use WithDefaultCallOptions(MaxCallRecvMsgSize(s)) instead.  Will
+// be supported throughout 1.x.
 func WithMaxMsgSize(s int) DialOption {
 	return WithDefaultCallOptions(MaxCallRecvMsgSize(s))
 }
@@ -159,7 +161,8 @@ func WithDefaultCallOptions(cos ...CallOption) DialOption {
 // WithCodec returns a DialOption which sets a codec for message marshaling and
 // unmarshaling.
 //
-// Deprecated: use WithDefaultCallOptions(CallCustomCodec(c)) instead.
+// Deprecated: use WithDefaultCallOptions(ForceCodec(_)) instead.  Will be
+// supported throughout 1.x.
 func WithCodec(c Codec) DialOption {
 	return WithDefaultCallOptions(CallCustomCodec(c))
 }
@@ -168,7 +171,7 @@ func WithCodec(c Codec) DialOption {
 // message compression. It has lower priority than the compressor set by the
 // UseCompressor CallOption.
 //
-// Deprecated: use UseCompressor instead.
+// Deprecated: use UseCompressor instead.  Will be supported throughout 1.x.
 func WithCompressor(cp Compressor) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.cp = cp
@@ -183,7 +186,8 @@ func WithCompressor(cp Compressor) DialOption {
 // message.  If no compressor is registered for the encoding, an Unimplemented
 // status error will be returned.
 //
-// Deprecated: use encoding.RegisterCompressor instead.
+// Deprecated: use encoding.RegisterCompressor instead.  Will be supported
+// throughout 1.x.
 func WithDecompressor(dc Decompressor) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.dc = dc
@@ -194,7 +198,7 @@ func WithDecompressor(dc Decompressor) DialOption {
 // Name resolver will be ignored if this DialOption is specified.
 //
 // Deprecated: use the new balancer APIs in balancer package and
-// WithBalancerName.
+// WithBalancerName.  Will be removed in a future 1.x release.
 func WithBalancer(b Balancer) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.balancerBuilder = &balancerWrapperBuilder{
@@ -210,7 +214,8 @@ func WithBalancer(b Balancer) DialOption {
 // The balancer cannot be overridden by balancer option specified by service
 // config.
 //
-// This is an EXPERIMENTAL API.
+// Deprecated: use WithDefaultServiceConfig and WithDisableServiceConfig
+// instead.  Will be removed in a future 1.x release.
 func WithBalancerName(balancerName string) DialOption {
 	builder := balancer.Get(balancerName)
 	if builder == nil {
@@ -231,9 +236,10 @@ func withResolverBuilder(b resolver.Builder) DialOption {
 // WithServiceConfig returns a DialOption which has a channel to read the
 // service configuration.
 //
-// Deprecated: service config should be received through name resolver, as
-// specified here.
-// https://github.com/grpc/grpc/blob/master/doc/service_config.md
+// Deprecated: service config should be received through name resolver or via
+// WithDefaultServiceConfig, as specified at
+// https://github.com/grpc/grpc/blob/master/doc/service_config.md.  Will be
+// removed in a future 1.x release.
 func WithServiceConfig(c <-chan ServiceConfig) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.scChan = c
@@ -286,7 +292,8 @@ func WithInsecure() DialOption {
 }
 
 // WithTransportCredentials returns a DialOption which configures a connection
-// level security credentials (e.g., TLS/SSL).
+// level security credentials (e.g., TLS/SSL). This should not be used together
+// with WithCredentialsBundle.
 func WithTransportCredentials(creds credentials.TransportCredentials) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.copts.TransportCredentials = creds
@@ -301,36 +308,55 @@ func WithPerRPCCredentials(creds credentials.PerRPCCredentials) DialOption {
 	})
 }
 
+// WithCredentialsBundle returns a DialOption to set a credentials bundle for
+// the ClientConn.WithCreds. This should not be used together with
+// WithTransportCredentials.
+//
+// This API is experimental.
+func WithCredentialsBundle(b credentials.Bundle) DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.copts.CredsBundle = b
+	})
+}
+
 // WithTimeout returns a DialOption that configures a timeout for dialing a
 // ClientConn initially. This is valid if and only if WithBlock() is present.
 //
-// Deprecated: use DialContext and context.WithTimeout instead.
+// Deprecated: use DialContext and context.WithTimeout instead.  Will be
+// supported throughout 1.x.
 func WithTimeout(d time.Duration) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.timeout = d
 	})
 }
 
-func withContextDialer(f func(context.Context, string) (net.Conn, error)) DialOption {
+// WithContextDialer returns a DialOption that sets a dialer to create
+// connections. If FailOnNonTempDialError() is set to true, and an error is
+// returned by f, gRPC checks the error's Temporary() method to decide if it
+// should try to reconnect to the network address.
+func WithContextDialer(f func(context.Context, string) (net.Conn, error)) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.copts.Dialer = f
 	})
 }
 
 func init() {
-	internal.WithContextDialer = withContextDialer
 	internal.WithResolverBuilder = withResolverBuilder
+	internal.WithHealthCheckFunc = withHealthCheckFunc
 }
 
 // WithDialer returns a DialOption that specifies a function to use for dialing
 // network addresses. If FailOnNonTempDialError() is set to true, and an error
 // is returned by f, gRPC checks the error's Temporary() method to decide if it
 // should try to reconnect to the network address.
+//
+// Deprecated: use WithContextDialer instead.  Will be supported throughout
+// 1.x.
 func WithDialer(f func(string, time.Duration) (net.Conn, error)) DialOption {
-	return withContextDialer(
+	return WithContextDialer(
 		func(ctx context.Context, addr string) (net.Conn, error) {
 			if deadline, ok := ctx.Deadline(); ok {
-				return f(addr, deadline.Sub(time.Now()))
+				return f(addr, time.Until(deadline))
 			}
 			return f(addr, 0)
 		})
@@ -349,6 +375,9 @@ func WithStatsHandler(h stats.Handler) DialOption {
 // error, gRPC will fail the connection to the network address and won't try to
 // reconnect. The default value of FailOnNonTempDialError is false.
 //
+// FailOnNonTempDialError only affects the initial dial, and does not do
+// anything useful unless you are also using WithBlock().
+//
 // This is an EXPERIMENTAL API.
 func FailOnNonTempDialError(f bool) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
@@ -367,6 +396,10 @@ func WithUserAgent(s string) DialOption {
 // WithKeepaliveParams returns a DialOption that specifies keepalive parameters
 // for the client transport.
 func WithKeepaliveParams(kp keepalive.ClientParameters) DialOption {
+	if kp.Time < internal.KeepaliveMinPingTime {
+		grpclog.Warningf("Adjusting keepalive ping interval to minimum period of %v", internal.KeepaliveMinPingTime)
+		kp.Time = internal.KeepaliveMinPingTime
+	}
 	return newFuncDialOption(func(o *dialOptions) {
 		o.copts.KeepaliveParams = kp
 	})
@@ -380,6 +413,17 @@ func WithUnaryInterceptor(f UnaryClientInterceptor) DialOption {
 	})
 }
 
+// WithChainUnaryInterceptor returns a DialOption that specifies the chained
+// interceptor for unary RPCs. The first interceptor will be the outer most,
+// while the last interceptor will be the inner most wrapper around the real call.
+// All interceptors added by this method will be chained, and the interceptor
+// defined by WithUnaryInterceptor will always be prepended to the chain.
+func WithChainUnaryInterceptor(interceptors ...UnaryClientInterceptor) DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.chainUnaryInts = append(o.chainUnaryInts, interceptors...)
+	})
+}
+
 // WithStreamInterceptor returns a DialOption that specifies the interceptor for
 // streaming RPCs.
 func WithStreamInterceptor(f StreamClientInterceptor) DialOption {
@@ -388,6 +432,17 @@ func WithStreamInterceptor(f StreamClientInterceptor) DialOption {
 	})
 }
 
+// WithChainStreamInterceptor returns a DialOption that specifies the chained
+// interceptor for unary RPCs. The first interceptor will be the outer most,
+// while the last interceptor will be the inner most wrapper around the real call.
+// All interceptors added by this method will be chained, and the interceptor
+// defined by WithStreamInterceptor will always be prepended to the chain.
+func WithChainStreamInterceptor(interceptors ...StreamClientInterceptor) DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.chainStreamInts = append(o.chainStreamInts, interceptors...)
+	})
+}
+
 // WithAuthority returns a DialOption that specifies the value to be used as the
 // :authority pseudo-header. This value only works with WithInsecure and has no
 // effect if TransportCredentials are present.
@@ -406,15 +461,32 @@ func WithChannelzParentID(id int64) DialOption {
 	})
 }
 
-// WithDisableServiceConfig returns a DialOption that causes grpc to ignore any
+// WithDisableServiceConfig returns a DialOption that causes gRPC to ignore any
 // service config provided by the resolver and provides a hint to the resolver
 // to not fetch service configs.
+//
+// Note that this dial option only disables service config from resolver. If
+// default service config is provided, gRPC will use the default service config.
 func WithDisableServiceConfig() DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.disableServiceConfig = true
 	})
 }
 
+// WithDefaultServiceConfig returns a DialOption that configures the default
+// service config, which will be used in cases where:
+//
+// 1. WithDisableServiceConfig is also used.
+// 2. Resolver does not return a service config or if the resolver returns an
+//    invalid service config.
+//
+// This API is EXPERIMENTAL.
+func WithDefaultServiceConfig(s string) DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.defaultServiceConfigRawJSON = &s
+	})
+}
+
 // WithDisableRetry returns a DialOption that disables retries, even if the
 // service config enables them.  This does not impact transparent retries, which
 // will happen automatically if no data is written to the wire or if the RPC is
@@ -439,12 +511,44 @@ func WithMaxHeaderListSize(s uint32) DialOption {
 	})
 }
 
+// WithDisableHealthCheck disables the LB channel health checking for all
+// SubConns of this ClientConn.
+//
+// This API is EXPERIMENTAL.
+func WithDisableHealthCheck() DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.disableHealthCheck = true
+	})
+}
+
+// withHealthCheckFunc replaces the default health check function with the
+// provided one. It makes tests easier to change the health check function.
+//
+// For testing purpose only.
+func withHealthCheckFunc(f internal.HealthChecker) DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.healthCheckFunc = f
+	})
+}
+
 func defaultDialOptions() dialOptions {
 	return dialOptions{
-		disableRetry: !envconfig.Retry,
+		disableRetry:    !envconfig.Retry,
+		healthCheckFunc: internal.HealthCheckFunc,
 		copts: transport.ConnectOptions{
 			WriteBufferSize: defaultWriteBufSize,
 			ReadBufferSize:  defaultReadBufSize,
 		},
 	}
 }
+
+// withGetMinConnectDeadline specifies the function that clientconn uses to
+// get minConnectDeadline. This can be used to make connection attempts happen
+// faster/slower.
+//
+// For testing purpose only.
+func withMinConnectDeadline(f func() time.Duration) DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.minConnectTimeout = f
+	})
+}
diff --git a/vendor/google.golang.org/grpc/encoding/encoding.go b/vendor/google.golang.org/grpc/encoding/encoding.go
index ade8b7ce..30a75da9 100644
--- a/vendor/google.golang.org/grpc/encoding/encoding.go
+++ b/vendor/google.golang.org/grpc/encoding/encoding.go
@@ -102,10 +102,10 @@ func RegisterCodec(codec Codec) {
 	if codec == nil {
 		panic("cannot register a nil Codec")
 	}
-	contentSubtype := strings.ToLower(codec.Name())
-	if contentSubtype == "" {
-		panic("cannot register Codec with empty string result for String()")
+	if codec.Name() == "" {
+		panic("cannot register Codec with empty string result for Name()")
 	}
+	contentSubtype := strings.ToLower(codec.Name())
 	registeredCodecs[contentSubtype] = codec
 }
 
diff --git a/vendor/google.golang.org/grpc/go.mod b/vendor/google.golang.org/grpc/go.mod
new file mode 100644
index 00000000..c1a8340c
--- /dev/null
+++ b/vendor/google.golang.org/grpc/go.mod
@@ -0,0 +1,19 @@
+module google.golang.org/grpc
+
+require (
+	cloud.google.com/go v0.26.0 // indirect
+	github.com/BurntSushi/toml v0.3.1 // indirect
+	github.com/client9/misspell v0.3.4
+	github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b
+	github.com/golang/mock v1.1.1
+	github.com/golang/protobuf v1.2.0
+	github.com/google/go-cmp v0.2.0
+	golang.org/x/lint v0.0.0-20190313153728-d0100b6bd8b3
+	golang.org/x/net v0.0.0-20190311183353-d8887717615a
+	golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be
+	golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a
+	golang.org/x/tools v0.0.0-20190524140312-2c0ae7006135
+	google.golang.org/appengine v1.1.0 // indirect
+	google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8
+	honnef.co/go/tools v0.0.0-20190523083050-ea95bdfd59fc
+)
diff --git a/vendor/google.golang.org/grpc/go.sum b/vendor/google.golang.org/grpc/go.sum
new file mode 100644
index 00000000..741677d2
--- /dev/null
+++ b/vendor/google.golang.org/grpc/go.sum
@@ -0,0 +1,37 @@
+cloud.google.com/go v0.26.0 h1:e0WKqKTd5BnrG8aKH3J3h+QvEIQtSUcf2n5UZ5ZgLtQ=
+cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/client9/misspell v0.3.4 h1:ta993UF76GwbvJcIo3Y68y/M3WxlpEHPWIGDkJYwzJI=
+github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b h1:VKtxabqXZkF25pY9ekfRL6a582T4P37/31XEstQ5p58=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
+github.com/golang/mock v1.1.1 h1:G5FRp8JnTd7RQH5kemVNlMeyXQAztQ3mOWV95KxsXH8=
+github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
+github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/google/go-cmp v0.2.0 h1:+dTQ8DZQJz0Mb/HjFlkptS1FeQ4cWSnN941F8aEG4SQ=
+github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/lint v0.0.0-20190313153728-d0100b6bd8b3 h1:XQyxROzUlZH+WIQwySDgnISgOivlhjIEwaQaJEJrrN0=
+golang.org/x/lint v0.0.0-20190313153728-d0100b6bd8b3/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a h1:oWX7TPOiFAMXLq8o0ikBYfCJVlRHBcsciT5bXOrH628=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be h1:vEDujvNQGv4jgYKudGeI/+DAX4Jffq6hpD55MmoEvKs=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58 h1:8gQV6CLnAEikrhgkHFbMAEhagSSnXWGV915qUMm9mrU=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a h1:1BGLXjeY4akVXGgbC9HugT3Jv3hCI0z56oJR5vAMgBU=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/tools v0.0.0-20190311212946-11955173bddd h1:/e+gpKk9r3dJobndpTytxS2gOy6m5uvpg+ISQoEcusQ=
+golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
+golang.org/x/tools v0.0.0-20190524140312-2c0ae7006135 h1:5Beo0mZN8dRzgrMMkDp0jc8YXQKx9DiJ2k1dkvGsn5A=
+golang.org/x/tools v0.0.0-20190524140312-2c0ae7006135/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=
+google.golang.org/appengine v1.1.0 h1:igQkv0AAhEIvTEpD5LIpAfav2eeVO9HBTjvKHVJPRSs=
+google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8 h1:Nw54tB0rB7hY/N0NQvRW8DG4Yk3Q6T9cu9RcFQDu1tc=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
+honnef.co/go/tools v0.0.0-20190523083050-ea95bdfd59fc h1:/hemPrYIhOhy8zYrNj+069zDB68us2sMGsfkFJO0iZs=
+honnef.co/go/tools v0.0.0-20190523083050-ea95bdfd59fc/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
diff --git a/vendor/google.golang.org/grpc/go16.go b/vendor/google.golang.org/grpc/go16.go
deleted file mode 100644
index b1db21af..00000000
--- a/vendor/google.golang.org/grpc/go16.go
+++ /dev/null
@@ -1,71 +0,0 @@
-// +build go1.6,!go1.7
-
-/*
- *
- * Copyright 2016 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package grpc
-
-import (
-	"fmt"
-	"io"
-	"net"
-	"net/http"
-
-	"golang.org/x/net/context"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/internal/transport"
-	"google.golang.org/grpc/status"
-)
-
-// dialContext connects to the address on the named network.
-func dialContext(ctx context.Context, network, address string) (net.Conn, error) {
-	return (&net.Dialer{Cancel: ctx.Done()}).Dial(network, address)
-}
-
-func sendHTTPRequest(ctx context.Context, req *http.Request, conn net.Conn) error {
-	req.Cancel = ctx.Done()
-	if err := req.Write(conn); err != nil {
-		return fmt.Errorf("failed to write the HTTP request: %v", err)
-	}
-	return nil
-}
-
-// toRPCErr converts an error into an error from the status package.
-func toRPCErr(err error) error {
-	if err == nil || err == io.EOF {
-		return err
-	}
-	if err == io.ErrUnexpectedEOF {
-		return status.Error(codes.Internal, err.Error())
-	}
-	if _, ok := status.FromError(err); ok {
-		return err
-	}
-	switch e := err.(type) {
-	case transport.ConnectionError:
-		return status.Error(codes.Unavailable, e.Desc)
-	default:
-		switch err {
-		case context.DeadlineExceeded:
-			return status.Error(codes.DeadlineExceeded, err.Error())
-		case context.Canceled:
-			return status.Error(codes.Canceled, err.Error())
-		}
-	}
-	return status.Error(codes.Unknown, err.Error())
-}
diff --git a/vendor/google.golang.org/grpc/go17.go b/vendor/google.golang.org/grpc/go17.go
deleted file mode 100644
index 71a72e8f..00000000
--- a/vendor/google.golang.org/grpc/go17.go
+++ /dev/null
@@ -1,72 +0,0 @@
-// +build go1.7
-
-/*
- *
- * Copyright 2016 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package grpc
-
-import (
-	"context"
-	"fmt"
-	"io"
-	"net"
-	"net/http"
-
-	netctx "golang.org/x/net/context"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/internal/transport"
-	"google.golang.org/grpc/status"
-)
-
-// dialContext connects to the address on the named network.
-func dialContext(ctx context.Context, network, address string) (net.Conn, error) {
-	return (&net.Dialer{}).DialContext(ctx, network, address)
-}
-
-func sendHTTPRequest(ctx context.Context, req *http.Request, conn net.Conn) error {
-	req = req.WithContext(ctx)
-	if err := req.Write(conn); err != nil {
-		return fmt.Errorf("failed to write the HTTP request: %v", err)
-	}
-	return nil
-}
-
-// toRPCErr converts an error into an error from the status package.
-func toRPCErr(err error) error {
-	if err == nil || err == io.EOF {
-		return err
-	}
-	if err == io.ErrUnexpectedEOF {
-		return status.Error(codes.Internal, err.Error())
-	}
-	if _, ok := status.FromError(err); ok {
-		return err
-	}
-	switch e := err.(type) {
-	case transport.ConnectionError:
-		return status.Error(codes.Unavailable, e.Desc)
-	default:
-		switch err {
-		case context.DeadlineExceeded, netctx.DeadlineExceeded:
-			return status.Error(codes.DeadlineExceeded, err.Error())
-		case context.Canceled, netctx.Canceled:
-			return status.Error(codes.Canceled, err.Error())
-		}
-	}
-	return status.Error(codes.Unknown, err.Error())
-}
diff --git a/vendor/google.golang.org/grpc/grpclog/grpclog.go b/vendor/google.golang.org/grpc/grpclog/grpclog.go
index 1fabb11e..51bb9457 100644
--- a/vendor/google.golang.org/grpc/grpclog/grpclog.go
+++ b/vendor/google.golang.org/grpc/grpclog/grpclog.go
@@ -18,7 +18,7 @@
 
 // Package grpclog defines logging for grpc.
 //
-// All logs in transport package only go to verbose level 2.
+// All logs in transport and grpclb packages only go to verbose level 2.
 // All logs in other packages in grpc are logged in spite of the verbosity level.
 //
 // In the default logger,
diff --git a/vendor/google.golang.org/grpc/install_gae.sh b/vendor/google.golang.org/grpc/install_gae.sh
index d4236f3b..7c7bcada 100755
--- a/vendor/google.golang.org/grpc/install_gae.sh
+++ b/vendor/google.golang.org/grpc/install_gae.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
 TMP=$(mktemp -d /tmp/sdk.XXX) \
-&& curl -o $TMP.zip "https://storage.googleapis.com/appengine-sdks/featured/go_appengine_sdk_linux_amd64-1.9.64.zip" \
+&& curl -o $TMP.zip "https://storage.googleapis.com/appengine-sdks/featured/go_appengine_sdk_linux_amd64-1.9.68.zip" \
 && unzip -q $TMP.zip -d $TMP \
 && export PATH="$PATH:$TMP/go_appengine"
diff --git a/vendor/google.golang.org/grpc/interceptor.go b/vendor/google.golang.org/grpc/interceptor.go
index 1f6ef678..8b735002 100644
--- a/vendor/google.golang.org/grpc/interceptor.go
+++ b/vendor/google.golang.org/grpc/interceptor.go
@@ -19,7 +19,7 @@
 package grpc
 
 import (
-	"golang.org/x/net/context"
+	"context"
 )
 
 // UnaryInvoker is called by UnaryClientInterceptor to complete RPCs.
diff --git a/vendor/google.golang.org/grpc/internal/balancerload/load.go b/vendor/google.golang.org/grpc/internal/balancerload/load.go
new file mode 100644
index 00000000..3a905d96
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/balancerload/load.go
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2019 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Package balancerload defines APIs to parse server loads in trailers. The
+// parsed loads are sent to balancers in DoneInfo.
+package balancerload
+
+import (
+	"google.golang.org/grpc/metadata"
+)
+
+// Parser converts loads from metadata into a concrete type.
+type Parser interface {
+	// Parse parses loads from metadata.
+	Parse(md metadata.MD) interface{}
+}
+
+var parser Parser
+
+// SetParser sets the load parser.
+//
+// Not mutex-protected, should be called before any gRPC functions.
+func SetParser(lr Parser) {
+	parser = lr
+}
+
+// Parse calls parser.Read().
+func Parse(md metadata.MD) interface{} {
+	if parser == nil {
+		return nil
+	}
+	return parser.Parse(md)
+}
diff --git a/vendor/google.golang.org/grpc/internal/binarylog/binarylog.go b/vendor/google.golang.org/grpc/internal/binarylog/binarylog.go
new file mode 100644
index 00000000..fee6aecd
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/binarylog/binarylog.go
@@ -0,0 +1,167 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package binarylog implementation binary logging as defined in
+// https://github.com/grpc/proposal/blob/master/A16-binary-logging.md.
+package binarylog
+
+import (
+	"fmt"
+	"os"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+// Logger is the global binary logger. It can be used to get binary logger for
+// each method.
+type Logger interface {
+	getMethodLogger(methodName string) *MethodLogger
+}
+
+// binLogger is the global binary logger for the binary. One of this should be
+// built at init time from the configuration (environment varialbe or flags).
+//
+// It is used to get a methodLogger for each individual method.
+var binLogger Logger
+
+// SetLogger sets the binarg logger.
+//
+// Only call this at init time.
+func SetLogger(l Logger) {
+	binLogger = l
+}
+
+// GetMethodLogger returns the methodLogger for the given methodName.
+//
+// methodName should be in the format of "/service/method".
+//
+// Each methodLogger returned by this method is a new instance. This is to
+// generate sequence id within the call.
+func GetMethodLogger(methodName string) *MethodLogger {
+	if binLogger == nil {
+		return nil
+	}
+	return binLogger.getMethodLogger(methodName)
+}
+
+func init() {
+	const envStr = "GRPC_BINARY_LOG_FILTER"
+	configStr := os.Getenv(envStr)
+	binLogger = NewLoggerFromConfigString(configStr)
+}
+
+type methodLoggerConfig struct {
+	// Max length of header and message.
+	hdr, msg uint64
+}
+
+type logger struct {
+	all      *methodLoggerConfig
+	services map[string]*methodLoggerConfig
+	methods  map[string]*methodLoggerConfig
+
+	blacklist map[string]struct{}
+}
+
+// newEmptyLogger creates an empty logger. The map fields need to be filled in
+// using the set* functions.
+func newEmptyLogger() *logger {
+	return &logger{}
+}
+
+// Set method logger for "*".
+func (l *logger) setDefaultMethodLogger(ml *methodLoggerConfig) error {
+	if l.all != nil {
+		return fmt.Errorf("conflicting global rules found")
+	}
+	l.all = ml
+	return nil
+}
+
+// Set method logger for "service/*".
+//
+// New methodLogger with same service overrides the old one.
+func (l *logger) setServiceMethodLogger(service string, ml *methodLoggerConfig) error {
+	if _, ok := l.services[service]; ok {
+		return fmt.Errorf("conflicting rules for service %v found", service)
+	}
+	if l.services == nil {
+		l.services = make(map[string]*methodLoggerConfig)
+	}
+	l.services[service] = ml
+	return nil
+}
+
+// Set method logger for "service/method".
+//
+// New methodLogger with same method overrides the old one.
+func (l *logger) setMethodMethodLogger(method string, ml *methodLoggerConfig) error {
+	if _, ok := l.blacklist[method]; ok {
+		return fmt.Errorf("conflicting rules for method %v found", method)
+	}
+	if _, ok := l.methods[method]; ok {
+		return fmt.Errorf("conflicting rules for method %v found", method)
+	}
+	if l.methods == nil {
+		l.methods = make(map[string]*methodLoggerConfig)
+	}
+	l.methods[method] = ml
+	return nil
+}
+
+// Set blacklist method for "-service/method".
+func (l *logger) setBlacklist(method string) error {
+	if _, ok := l.blacklist[method]; ok {
+		return fmt.Errorf("conflicting rules for method %v found", method)
+	}
+	if _, ok := l.methods[method]; ok {
+		return fmt.Errorf("conflicting rules for method %v found", method)
+	}
+	if l.blacklist == nil {
+		l.blacklist = make(map[string]struct{})
+	}
+	l.blacklist[method] = struct{}{}
+	return nil
+}
+
+// getMethodLogger returns the methodLogger for the given methodName.
+//
+// methodName should be in the format of "/service/method".
+//
+// Each methodLogger returned by this method is a new instance. This is to
+// generate sequence id within the call.
+func (l *logger) getMethodLogger(methodName string) *MethodLogger {
+	s, m, err := parseMethodName(methodName)
+	if err != nil {
+		grpclog.Infof("binarylogging: failed to parse %q: %v", methodName, err)
+		return nil
+	}
+	if ml, ok := l.methods[s+"/"+m]; ok {
+		return newMethodLogger(ml.hdr, ml.msg)
+	}
+	if _, ok := l.blacklist[s+"/"+m]; ok {
+		return nil
+	}
+	if ml, ok := l.services[s]; ok {
+		return newMethodLogger(ml.hdr, ml.msg)
+	}
+	if l.all == nil {
+		return nil
+	}
+	return newMethodLogger(l.all.hdr, l.all.msg)
+}
diff --git a/vendor/google.golang.org/grpc/internal/binarylog/binarylog_testutil.go b/vendor/google.golang.org/grpc/internal/binarylog/binarylog_testutil.go
new file mode 100644
index 00000000..1ee00a39
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/binarylog/binarylog_testutil.go
@@ -0,0 +1,42 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// This file contains exported variables/functions that are exported for testing
+// only.
+//
+// An ideal way for this would be to put those in a *_test.go but in binarylog
+// package. But this doesn't work with staticcheck with go module. Error was:
+// "MdToMetadataProto not declared by package binarylog". This could be caused
+// by the way staticcheck looks for files for a certain package, which doesn't
+// support *_test.go files.
+//
+// Move those to binary_test.go when staticcheck is fixed.
+
+package binarylog
+
+var (
+	// AllLogger is a logger that logs all headers/messages for all RPCs. It's
+	// for testing only.
+	AllLogger = NewLoggerFromConfigString("*")
+	// MdToMetadataProto converts metadata to a binary logging proto message.
+	// It's for testing only.
+	MdToMetadataProto = mdToMetadataProto
+	// AddrToProto converts an address to a binary logging proto message. It's
+	// for testing only.
+	AddrToProto = addrToProto
+)
diff --git a/vendor/google.golang.org/grpc/internal/binarylog/env_config.go b/vendor/google.golang.org/grpc/internal/binarylog/env_config.go
new file mode 100644
index 00000000..4cc2525d
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/binarylog/env_config.go
@@ -0,0 +1,210 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package binarylog
+
+import (
+	"errors"
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+// NewLoggerFromConfigString reads the string and build a logger. It can be used
+// to build a new logger and assign it to binarylog.Logger.
+//
+// Example filter config strings:
+//  - "" Nothing will be logged
+//  - "*" All headers and messages will be fully logged.
+//  - "*{h}" Only headers will be logged.
+//  - "*{m:256}" Only the first 256 bytes of each message will be logged.
+//  - "Foo/*" Logs every method in service Foo
+//  - "Foo/*,-Foo/Bar" Logs every method in service Foo except method /Foo/Bar
+//  - "Foo/*,Foo/Bar{m:256}" Logs the first 256 bytes of each message in method
+//    /Foo/Bar, logs all headers and messages in every other method in service
+//    Foo.
+//
+// If two configs exist for one certain method or service, the one specified
+// later overrides the privous config.
+func NewLoggerFromConfigString(s string) Logger {
+	if s == "" {
+		return nil
+	}
+	l := newEmptyLogger()
+	methods := strings.Split(s, ",")
+	for _, method := range methods {
+		if err := l.fillMethodLoggerWithConfigString(method); err != nil {
+			grpclog.Warningf("failed to parse binary log config: %v", err)
+			return nil
+		}
+	}
+	return l
+}
+
+// fillMethodLoggerWithConfigString parses config, creates methodLogger and adds
+// it to the right map in the logger.
+func (l *logger) fillMethodLoggerWithConfigString(config string) error {
+	// "" is invalid.
+	if config == "" {
+		return errors.New("empty string is not a valid method binary logging config")
+	}
+
+	// "-service/method", blacklist, no * or {} allowed.
+	if config[0] == '-' {
+		s, m, suffix, err := parseMethodConfigAndSuffix(config[1:])
+		if err != nil {
+			return fmt.Errorf("invalid config: %q, %v", config, err)
+		}
+		if m == "*" {
+			return fmt.Errorf("invalid config: %q, %v", config, "* not allowd in blacklist config")
+		}
+		if suffix != "" {
+			return fmt.Errorf("invalid config: %q, %v", config, "header/message limit not allowed in blacklist config")
+		}
+		if err := l.setBlacklist(s + "/" + m); err != nil {
+			return fmt.Errorf("invalid config: %v", err)
+		}
+		return nil
+	}
+
+	// "*{h:256;m:256}"
+	if config[0] == '*' {
+		hdr, msg, err := parseHeaderMessageLengthConfig(config[1:])
+		if err != nil {
+			return fmt.Errorf("invalid config: %q, %v", config, err)
+		}
+		if err := l.setDefaultMethodLogger(&methodLoggerConfig{hdr: hdr, msg: msg}); err != nil {
+			return fmt.Errorf("invalid config: %v", err)
+		}
+		return nil
+	}
+
+	s, m, suffix, err := parseMethodConfigAndSuffix(config)
+	if err != nil {
+		return fmt.Errorf("invalid config: %q, %v", config, err)
+	}
+	hdr, msg, err := parseHeaderMessageLengthConfig(suffix)
+	if err != nil {
+		return fmt.Errorf("invalid header/message length config: %q, %v", suffix, err)
+	}
+	if m == "*" {
+		if err := l.setServiceMethodLogger(s, &methodLoggerConfig{hdr: hdr, msg: msg}); err != nil {
+			return fmt.Errorf("invalid config: %v", err)
+		}
+	} else {
+		if err := l.setMethodMethodLogger(s+"/"+m, &methodLoggerConfig{hdr: hdr, msg: msg}); err != nil {
+			return fmt.Errorf("invalid config: %v", err)
+		}
+	}
+	return nil
+}
+
+const (
+	// TODO: this const is only used by env_config now. But could be useful for
+	// other config. Move to binarylog.go if necessary.
+	maxUInt = ^uint64(0)
+
+	// For "p.s/m" plus any suffix. Suffix will be parsed again. See test for
+	// expected output.
+	longMethodConfigRegexpStr = `^([\w./]+)/((?:\w+)|[*])(.+)?$`
+
+	// For suffix from above, "{h:123,m:123}". See test for expected output.
+	optionalLengthRegexpStr      = `(?::(\d+))?` // Optional ":123".
+	headerConfigRegexpStr        = `^{h` + optionalLengthRegexpStr + `}$`
+	messageConfigRegexpStr       = `^{m` + optionalLengthRegexpStr + `}$`
+	headerMessageConfigRegexpStr = `^{h` + optionalLengthRegexpStr + `;m` + optionalLengthRegexpStr + `}$`
+)
+
+var (
+	longMethodConfigRegexp    = regexp.MustCompile(longMethodConfigRegexpStr)
+	headerConfigRegexp        = regexp.MustCompile(headerConfigRegexpStr)
+	messageConfigRegexp       = regexp.MustCompile(messageConfigRegexpStr)
+	headerMessageConfigRegexp = regexp.MustCompile(headerMessageConfigRegexpStr)
+)
+
+// Turn "service/method{h;m}" into "service", "method", "{h;m}".
+func parseMethodConfigAndSuffix(c string) (service, method, suffix string, _ error) {
+	// Regexp result:
+	//
+	// in:  "p.s/m{h:123,m:123}",
+	// out: []string{"p.s/m{h:123,m:123}", "p.s", "m", "{h:123,m:123}"},
+	match := longMethodConfigRegexp.FindStringSubmatch(c)
+	if match == nil {
+		return "", "", "", fmt.Errorf("%q contains invalid substring", c)
+	}
+	service = match[1]
+	method = match[2]
+	suffix = match[3]
+	return
+}
+
+// Turn "{h:123;m:345}" into 123, 345.
+//
+// Return maxUInt if length is unspecified.
+func parseHeaderMessageLengthConfig(c string) (hdrLenStr, msgLenStr uint64, err error) {
+	if c == "" {
+		return maxUInt, maxUInt, nil
+	}
+	// Header config only.
+	if match := headerConfigRegexp.FindStringSubmatch(c); match != nil {
+		if s := match[1]; s != "" {
+			hdrLenStr, err = strconv.ParseUint(s, 10, 64)
+			if err != nil {
+				return 0, 0, fmt.Errorf("failed to convert %q to uint", s)
+			}
+			return hdrLenStr, 0, nil
+		}
+		return maxUInt, 0, nil
+	}
+
+	// Message config only.
+	if match := messageConfigRegexp.FindStringSubmatch(c); match != nil {
+		if s := match[1]; s != "" {
+			msgLenStr, err = strconv.ParseUint(s, 10, 64)
+			if err != nil {
+				return 0, 0, fmt.Errorf("failed to convert %q to uint", s)
+			}
+			return 0, msgLenStr, nil
+		}
+		return 0, maxUInt, nil
+	}
+
+	// Header and message config both.
+	if match := headerMessageConfigRegexp.FindStringSubmatch(c); match != nil {
+		// Both hdr and msg are specified, but one or two of them might be empty.
+		hdrLenStr = maxUInt
+		msgLenStr = maxUInt
+		if s := match[1]; s != "" {
+			hdrLenStr, err = strconv.ParseUint(s, 10, 64)
+			if err != nil {
+				return 0, 0, fmt.Errorf("failed to convert %q to uint", s)
+			}
+		}
+		if s := match[2]; s != "" {
+			msgLenStr, err = strconv.ParseUint(s, 10, 64)
+			if err != nil {
+				return 0, 0, fmt.Errorf("failed to convert %q to uint", s)
+			}
+		}
+		return hdrLenStr, msgLenStr, nil
+	}
+	return 0, 0, fmt.Errorf("%q contains invalid substring", c)
+}
diff --git a/vendor/google.golang.org/grpc/internal/binarylog/method_logger.go b/vendor/google.golang.org/grpc/internal/binarylog/method_logger.go
new file mode 100644
index 00000000..160f6e86
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/binarylog/method_logger.go
@@ -0,0 +1,423 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package binarylog
+
+import (
+	"net"
+	"strings"
+	"sync/atomic"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/golang/protobuf/ptypes"
+	pb "google.golang.org/grpc/binarylog/grpc_binarylog_v1"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/status"
+)
+
+type callIDGenerator struct {
+	id uint64
+}
+
+func (g *callIDGenerator) next() uint64 {
+	id := atomic.AddUint64(&g.id, 1)
+	return id
+}
+
+// reset is for testing only, and doesn't need to be thread safe.
+func (g *callIDGenerator) reset() {
+	g.id = 0
+}
+
+var idGen callIDGenerator
+
+// MethodLogger is the sub-logger for each method.
+type MethodLogger struct {
+	headerMaxLen, messageMaxLen uint64
+
+	callID          uint64
+	idWithinCallGen *callIDGenerator
+
+	sink Sink // TODO(blog): make this plugable.
+}
+
+func newMethodLogger(h, m uint64) *MethodLogger {
+	return &MethodLogger{
+		headerMaxLen:  h,
+		messageMaxLen: m,
+
+		callID:          idGen.next(),
+		idWithinCallGen: &callIDGenerator{},
+
+		sink: defaultSink, // TODO(blog): make it plugable.
+	}
+}
+
+// Log creates a proto binary log entry, and logs it to the sink.
+func (ml *MethodLogger) Log(c LogEntryConfig) {
+	m := c.toProto()
+	timestamp, _ := ptypes.TimestampProto(time.Now())
+	m.Timestamp = timestamp
+	m.CallId = ml.callID
+	m.SequenceIdWithinCall = ml.idWithinCallGen.next()
+
+	switch pay := m.Payload.(type) {
+	case *pb.GrpcLogEntry_ClientHeader:
+		m.PayloadTruncated = ml.truncateMetadata(pay.ClientHeader.GetMetadata())
+	case *pb.GrpcLogEntry_ServerHeader:
+		m.PayloadTruncated = ml.truncateMetadata(pay.ServerHeader.GetMetadata())
+	case *pb.GrpcLogEntry_Message:
+		m.PayloadTruncated = ml.truncateMessage(pay.Message)
+	}
+
+	ml.sink.Write(m)
+}
+
+func (ml *MethodLogger) truncateMetadata(mdPb *pb.Metadata) (truncated bool) {
+	if ml.headerMaxLen == maxUInt {
+		return false
+	}
+	var (
+		bytesLimit = ml.headerMaxLen
+		index      int
+	)
+	// At the end of the loop, index will be the first entry where the total
+	// size is greater than the limit:
+	//
+	// len(entry[:index]) <= ml.hdr && len(entry[:index+1]) > ml.hdr.
+	for ; index < len(mdPb.Entry); index++ {
+		entry := mdPb.Entry[index]
+		if entry.Key == "grpc-trace-bin" {
+			// "grpc-trace-bin" is a special key. It's kept in the log entry,
+			// but not counted towards the size limit.
+			continue
+		}
+		currentEntryLen := uint64(len(entry.Value))
+		if currentEntryLen > bytesLimit {
+			break
+		}
+		bytesLimit -= currentEntryLen
+	}
+	truncated = index < len(mdPb.Entry)
+	mdPb.Entry = mdPb.Entry[:index]
+	return truncated
+}
+
+func (ml *MethodLogger) truncateMessage(msgPb *pb.Message) (truncated bool) {
+	if ml.messageMaxLen == maxUInt {
+		return false
+	}
+	if ml.messageMaxLen >= uint64(len(msgPb.Data)) {
+		return false
+	}
+	msgPb.Data = msgPb.Data[:ml.messageMaxLen]
+	return true
+}
+
+// LogEntryConfig represents the configuration for binary log entry.
+type LogEntryConfig interface {
+	toProto() *pb.GrpcLogEntry
+}
+
+// ClientHeader configs the binary log entry to be a ClientHeader entry.
+type ClientHeader struct {
+	OnClientSide bool
+	Header       metadata.MD
+	MethodName   string
+	Authority    string
+	Timeout      time.Duration
+	// PeerAddr is required only when it's on server side.
+	PeerAddr net.Addr
+}
+
+func (c *ClientHeader) toProto() *pb.GrpcLogEntry {
+	// This function doesn't need to set all the fields (e.g. seq ID). The Log
+	// function will set the fields when necessary.
+	clientHeader := &pb.ClientHeader{
+		Metadata:   mdToMetadataProto(c.Header),
+		MethodName: c.MethodName,
+		Authority:  c.Authority,
+	}
+	if c.Timeout > 0 {
+		clientHeader.Timeout = ptypes.DurationProto(c.Timeout)
+	}
+	ret := &pb.GrpcLogEntry{
+		Type: pb.GrpcLogEntry_EVENT_TYPE_CLIENT_HEADER,
+		Payload: &pb.GrpcLogEntry_ClientHeader{
+			ClientHeader: clientHeader,
+		},
+	}
+	if c.OnClientSide {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_CLIENT
+	} else {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_SERVER
+	}
+	if c.PeerAddr != nil {
+		ret.Peer = addrToProto(c.PeerAddr)
+	}
+	return ret
+}
+
+// ServerHeader configs the binary log entry to be a ServerHeader entry.
+type ServerHeader struct {
+	OnClientSide bool
+	Header       metadata.MD
+	// PeerAddr is required only when it's on client side.
+	PeerAddr net.Addr
+}
+
+func (c *ServerHeader) toProto() *pb.GrpcLogEntry {
+	ret := &pb.GrpcLogEntry{
+		Type: pb.GrpcLogEntry_EVENT_TYPE_SERVER_HEADER,
+		Payload: &pb.GrpcLogEntry_ServerHeader{
+			ServerHeader: &pb.ServerHeader{
+				Metadata: mdToMetadataProto(c.Header),
+			},
+		},
+	}
+	if c.OnClientSide {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_CLIENT
+	} else {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_SERVER
+	}
+	if c.PeerAddr != nil {
+		ret.Peer = addrToProto(c.PeerAddr)
+	}
+	return ret
+}
+
+// ClientMessage configs the binary log entry to be a ClientMessage entry.
+type ClientMessage struct {
+	OnClientSide bool
+	// Message can be a proto.Message or []byte. Other messages formats are not
+	// supported.
+	Message interface{}
+}
+
+func (c *ClientMessage) toProto() *pb.GrpcLogEntry {
+	var (
+		data []byte
+		err  error
+	)
+	if m, ok := c.Message.(proto.Message); ok {
+		data, err = proto.Marshal(m)
+		if err != nil {
+			grpclog.Infof("binarylogging: failed to marshal proto message: %v", err)
+		}
+	} else if b, ok := c.Message.([]byte); ok {
+		data = b
+	} else {
+		grpclog.Infof("binarylogging: message to log is neither proto.message nor []byte")
+	}
+	ret := &pb.GrpcLogEntry{
+		Type: pb.GrpcLogEntry_EVENT_TYPE_CLIENT_MESSAGE,
+		Payload: &pb.GrpcLogEntry_Message{
+			Message: &pb.Message{
+				Length: uint32(len(data)),
+				Data:   data,
+			},
+		},
+	}
+	if c.OnClientSide {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_CLIENT
+	} else {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_SERVER
+	}
+	return ret
+}
+
+// ServerMessage configs the binary log entry to be a ServerMessage entry.
+type ServerMessage struct {
+	OnClientSide bool
+	// Message can be a proto.Message or []byte. Other messages formats are not
+	// supported.
+	Message interface{}
+}
+
+func (c *ServerMessage) toProto() *pb.GrpcLogEntry {
+	var (
+		data []byte
+		err  error
+	)
+	if m, ok := c.Message.(proto.Message); ok {
+		data, err = proto.Marshal(m)
+		if err != nil {
+			grpclog.Infof("binarylogging: failed to marshal proto message: %v", err)
+		}
+	} else if b, ok := c.Message.([]byte); ok {
+		data = b
+	} else {
+		grpclog.Infof("binarylogging: message to log is neither proto.message nor []byte")
+	}
+	ret := &pb.GrpcLogEntry{
+		Type: pb.GrpcLogEntry_EVENT_TYPE_SERVER_MESSAGE,
+		Payload: &pb.GrpcLogEntry_Message{
+			Message: &pb.Message{
+				Length: uint32(len(data)),
+				Data:   data,
+			},
+		},
+	}
+	if c.OnClientSide {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_CLIENT
+	} else {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_SERVER
+	}
+	return ret
+}
+
+// ClientHalfClose configs the binary log entry to be a ClientHalfClose entry.
+type ClientHalfClose struct {
+	OnClientSide bool
+}
+
+func (c *ClientHalfClose) toProto() *pb.GrpcLogEntry {
+	ret := &pb.GrpcLogEntry{
+		Type:    pb.GrpcLogEntry_EVENT_TYPE_CLIENT_HALF_CLOSE,
+		Payload: nil, // No payload here.
+	}
+	if c.OnClientSide {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_CLIENT
+	} else {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_SERVER
+	}
+	return ret
+}
+
+// ServerTrailer configs the binary log entry to be a ServerTrailer entry.
+type ServerTrailer struct {
+	OnClientSide bool
+	Trailer      metadata.MD
+	// Err is the status error.
+	Err error
+	// PeerAddr is required only when it's on client side and the RPC is trailer
+	// only.
+	PeerAddr net.Addr
+}
+
+func (c *ServerTrailer) toProto() *pb.GrpcLogEntry {
+	st, ok := status.FromError(c.Err)
+	if !ok {
+		grpclog.Info("binarylogging: error in trailer is not a status error")
+	}
+	var (
+		detailsBytes []byte
+		err          error
+	)
+	stProto := st.Proto()
+	if stProto != nil && len(stProto.Details) != 0 {
+		detailsBytes, err = proto.Marshal(stProto)
+		if err != nil {
+			grpclog.Infof("binarylogging: failed to marshal status proto: %v", err)
+		}
+	}
+	ret := &pb.GrpcLogEntry{
+		Type: pb.GrpcLogEntry_EVENT_TYPE_SERVER_TRAILER,
+		Payload: &pb.GrpcLogEntry_Trailer{
+			Trailer: &pb.Trailer{
+				Metadata:      mdToMetadataProto(c.Trailer),
+				StatusCode:    uint32(st.Code()),
+				StatusMessage: st.Message(),
+				StatusDetails: detailsBytes,
+			},
+		},
+	}
+	if c.OnClientSide {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_CLIENT
+	} else {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_SERVER
+	}
+	if c.PeerAddr != nil {
+		ret.Peer = addrToProto(c.PeerAddr)
+	}
+	return ret
+}
+
+// Cancel configs the binary log entry to be a Cancel entry.
+type Cancel struct {
+	OnClientSide bool
+}
+
+func (c *Cancel) toProto() *pb.GrpcLogEntry {
+	ret := &pb.GrpcLogEntry{
+		Type:    pb.GrpcLogEntry_EVENT_TYPE_CANCEL,
+		Payload: nil,
+	}
+	if c.OnClientSide {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_CLIENT
+	} else {
+		ret.Logger = pb.GrpcLogEntry_LOGGER_SERVER
+	}
+	return ret
+}
+
+// metadataKeyOmit returns whether the metadata entry with this key should be
+// omitted.
+func metadataKeyOmit(key string) bool {
+	switch key {
+	case "lb-token", ":path", ":authority", "content-encoding", "content-type", "user-agent", "te":
+		return true
+	case "grpc-trace-bin": // grpc-trace-bin is special because it's visiable to users.
+		return false
+	}
+	return strings.HasPrefix(key, "grpc-")
+}
+
+func mdToMetadataProto(md metadata.MD) *pb.Metadata {
+	ret := &pb.Metadata{}
+	for k, vv := range md {
+		if metadataKeyOmit(k) {
+			continue
+		}
+		for _, v := range vv {
+			ret.Entry = append(ret.Entry,
+				&pb.MetadataEntry{
+					Key:   k,
+					Value: []byte(v),
+				},
+			)
+		}
+	}
+	return ret
+}
+
+func addrToProto(addr net.Addr) *pb.Address {
+	ret := &pb.Address{}
+	switch a := addr.(type) {
+	case *net.TCPAddr:
+		if a.IP.To4() != nil {
+			ret.Type = pb.Address_TYPE_IPV4
+		} else if a.IP.To16() != nil {
+			ret.Type = pb.Address_TYPE_IPV6
+		} else {
+			ret.Type = pb.Address_TYPE_UNKNOWN
+			// Do not set address and port fields.
+			break
+		}
+		ret.Address = a.IP.String()
+		ret.IpPort = uint32(a.Port)
+	case *net.UnixAddr:
+		ret.Type = pb.Address_TYPE_UNIX
+		ret.Address = a.String()
+	default:
+		ret.Type = pb.Address_TYPE_UNKNOWN
+	}
+	return ret
+}
diff --git a/vendor/google.golang.org/grpc/internal/binarylog/regenerate.sh b/vendor/google.golang.org/grpc/internal/binarylog/regenerate.sh
new file mode 100755
index 00000000..113d40cb
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/binarylog/regenerate.sh
@@ -0,0 +1,33 @@
+#!/bin/bash
+# Copyright 2018 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -eux -o pipefail
+
+TMP=$(mktemp -d)
+
+function finish {
+  rm -rf "$TMP"
+}
+trap finish EXIT
+
+pushd "$TMP"
+mkdir -p grpc/binarylog/grpc_binarylog_v1
+curl https://raw.githubusercontent.com/grpc/grpc-proto/master/grpc/binlog/v1/binarylog.proto > grpc/binarylog/grpc_binarylog_v1/binarylog.proto
+
+protoc --go_out=plugins=grpc,paths=source_relative:. -I. grpc/binarylog/grpc_binarylog_v1/*.proto
+popd
+rm -f ./grpc_binarylog_v1/*.pb.go
+cp "$TMP"/grpc/binarylog/grpc_binarylog_v1/*.pb.go ../../binarylog/grpc_binarylog_v1/
+
diff --git a/vendor/google.golang.org/grpc/internal/binarylog/sink.go b/vendor/google.golang.org/grpc/internal/binarylog/sink.go
new file mode 100644
index 00000000..20d044f0
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/binarylog/sink.go
@@ -0,0 +1,162 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package binarylog
+
+import (
+	"bufio"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"sync"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+	pb "google.golang.org/grpc/binarylog/grpc_binarylog_v1"
+	"google.golang.org/grpc/grpclog"
+)
+
+var (
+	defaultSink Sink = &noopSink{} // TODO(blog): change this default (file in /tmp).
+)
+
+// SetDefaultSink sets the sink where binary logs will be written to.
+//
+// Not thread safe. Only set during initialization.
+func SetDefaultSink(s Sink) {
+	if defaultSink != nil {
+		defaultSink.Close()
+	}
+	defaultSink = s
+}
+
+// Sink writes log entry into the binary log sink.
+type Sink interface {
+	// Write will be called to write the log entry into the sink.
+	//
+	// It should be thread-safe so it can be called in parallel.
+	Write(*pb.GrpcLogEntry) error
+	// Close will be called when the Sink is replaced by a new Sink.
+	Close() error
+}
+
+type noopSink struct{}
+
+func (ns *noopSink) Write(*pb.GrpcLogEntry) error { return nil }
+func (ns *noopSink) Close() error                 { return nil }
+
+// newWriterSink creates a binary log sink with the given writer.
+//
+// Write() marshalls the proto message and writes it to the given writer. Each
+// message is prefixed with a 4 byte big endian unsigned integer as the length.
+//
+// No buffer is done, Close() doesn't try to close the writer.
+func newWriterSink(w io.Writer) *writerSink {
+	return &writerSink{out: w}
+}
+
+type writerSink struct {
+	out io.Writer
+}
+
+func (ws *writerSink) Write(e *pb.GrpcLogEntry) error {
+	b, err := proto.Marshal(e)
+	if err != nil {
+		grpclog.Infof("binary logging: failed to marshal proto message: %v", err)
+	}
+	hdr := make([]byte, 4)
+	binary.BigEndian.PutUint32(hdr, uint32(len(b)))
+	if _, err := ws.out.Write(hdr); err != nil {
+		return err
+	}
+	if _, err := ws.out.Write(b); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (ws *writerSink) Close() error { return nil }
+
+type bufWriteCloserSink struct {
+	mu     sync.Mutex
+	closer io.Closer
+	out    *writerSink   // out is built on buf.
+	buf    *bufio.Writer // buf is kept for flush.
+
+	writeStartOnce sync.Once
+	writeTicker    *time.Ticker
+}
+
+func (fs *bufWriteCloserSink) Write(e *pb.GrpcLogEntry) error {
+	// Start the write loop when Write is called.
+	fs.writeStartOnce.Do(fs.startFlushGoroutine)
+	fs.mu.Lock()
+	if err := fs.out.Write(e); err != nil {
+		fs.mu.Unlock()
+		return err
+	}
+	fs.mu.Unlock()
+	return nil
+}
+
+const (
+	bufFlushDuration = 60 * time.Second
+)
+
+func (fs *bufWriteCloserSink) startFlushGoroutine() {
+	fs.writeTicker = time.NewTicker(bufFlushDuration)
+	go func() {
+		for range fs.writeTicker.C {
+			fs.mu.Lock()
+			fs.buf.Flush()
+			fs.mu.Unlock()
+		}
+	}()
+}
+
+func (fs *bufWriteCloserSink) Close() error {
+	if fs.writeTicker != nil {
+		fs.writeTicker.Stop()
+	}
+	fs.mu.Lock()
+	fs.buf.Flush()
+	fs.closer.Close()
+	fs.out.Close()
+	fs.mu.Unlock()
+	return nil
+}
+
+func newBufWriteCloserSink(o io.WriteCloser) Sink {
+	bufW := bufio.NewWriter(o)
+	return &bufWriteCloserSink{
+		closer: o,
+		out:    newWriterSink(bufW),
+		buf:    bufW,
+	}
+}
+
+// NewTempFileSink creates a temp file and returns a Sink that writes to this
+// file.
+func NewTempFileSink() (Sink, error) {
+	tempFile, err := ioutil.TempFile("/tmp", "grpcgo_binarylog_*.txt")
+	if err != nil {
+		return nil, fmt.Errorf("failed to create temp file: %v", err)
+	}
+	return newBufWriteCloserSink(tempFile), nil
+}
diff --git a/vendor/google.golang.org/grpc/status/go16.go b/vendor/google.golang.org/grpc/internal/binarylog/util.go
similarity index 51%
rename from vendor/google.golang.org/grpc/status/go16.go
rename to vendor/google.golang.org/grpc/internal/binarylog/util.go
index e59b53e8..15dc7803 100644
--- a/vendor/google.golang.org/grpc/status/go16.go
+++ b/vendor/google.golang.org/grpc/internal/binarylog/util.go
@@ -1,5 +1,3 @@
-// +build go1.6,!go1.7
-
 /*
  *
  * Copyright 2018 gRPC authors.
@@ -18,25 +16,26 @@
  *
  */
 
-package status
+package binarylog
 
 import (
-	"golang.org/x/net/context"
-	"google.golang.org/grpc/codes"
+	"errors"
+	"strings"
 )
 
-// FromContextError converts a context error into a Status.  It returns a
-// Status with codes.OK if err is nil, or a Status with codes.Unknown if err is
-// non-nil and not a context error.
-func FromContextError(err error) *Status {
-	switch err {
-	case nil:
-		return New(codes.OK, "")
-	case context.DeadlineExceeded:
-		return New(codes.DeadlineExceeded, err.Error())
-	case context.Canceled:
-		return New(codes.Canceled, err.Error())
-	default:
-		return New(codes.Unknown, err.Error())
+// parseMethodName splits service and method from the input. It expects format
+// "/service/method".
+//
+// TODO: move to internal/grpcutil.
+func parseMethodName(methodName string) (service, method string, _ error) {
+	if !strings.HasPrefix(methodName, "/") {
+		return "", "", errors.New("invalid method name: should start with /")
+	}
+	methodName = methodName[1:]
+
+	pos := strings.LastIndex(methodName, "/")
+	if pos < 0 {
+		return "", "", errors.New("invalid method name: suffix /method is missing")
 	}
+	return methodName[:pos], methodName[pos+1:], nil
 }
diff --git a/vendor/google.golang.org/grpc/internal/channelz/funcs.go b/vendor/google.golang.org/grpc/internal/channelz/funcs.go
index 586a0336..f0744f99 100644
--- a/vendor/google.golang.org/grpc/internal/channelz/funcs.go
+++ b/vendor/google.golang.org/grpc/internal/channelz/funcs.go
@@ -24,19 +24,26 @@
 package channelz
 
 import (
+	"fmt"
 	"sort"
 	"sync"
 	"sync/atomic"
+	"time"
 
 	"google.golang.org/grpc/grpclog"
 )
 
+const (
+	defaultMaxTraceEntry int32 = 30
+)
+
 var (
 	db    dbWrapper
 	idGen idGenerator
 	// EntryPerPage defines the number of channelz entries to be shown on a web page.
-	EntryPerPage = 50
-	curState     int32
+	EntryPerPage  = int64(50)
+	curState      int32
+	maxTraceEntry = defaultMaxTraceEntry
 )
 
 // TurnOn turns on channelz data collection.
@@ -52,6 +59,22 @@ func IsOn() bool {
 	return atomic.CompareAndSwapInt32(&curState, 1, 1)
 }
 
+// SetMaxTraceEntry sets maximum number of trace entry per entity (i.e. channel/subchannel).
+// Setting it to 0 will disable channel tracing.
+func SetMaxTraceEntry(i int32) {
+	atomic.StoreInt32(&maxTraceEntry, i)
+}
+
+// ResetMaxTraceEntryToDefault resets the maximum number of trace entry per entity to default.
+func ResetMaxTraceEntryToDefault() {
+	atomic.StoreInt32(&maxTraceEntry, defaultMaxTraceEntry)
+}
+
+func getMaxTraceEntry() int {
+	i := atomic.LoadInt32(&maxTraceEntry)
+	return int(i)
+}
+
 // dbWarpper wraps around a reference to internal channelz data storage, and
 // provide synchronized functionality to set and get the reference.
 type dbWrapper struct {
@@ -73,9 +96,14 @@ func (d *dbWrapper) get() *channelMap {
 
 // NewChannelzStorage initializes channelz data storage and id generator.
 //
+// This function returns a cleanup function to wait for all channelz state to be reset by the
+// grpc goroutines when those entities get closed. By using this cleanup function, we make sure tests
+// don't mess up each other, i.e. lingering goroutine from previous test doing entity removal happen
+// to remove some entity just register by the new test, since the id space is the same.
+//
 // Note: This function is exported for testing purpose only. User should not call
 // it in most cases.
-func NewChannelzStorage() {
+func NewChannelzStorage() (cleanup func() error) {
 	db.set(&channelMap{
 		topLevelChannels: make(map[int64]struct{}),
 		channels:         make(map[int64]*channel),
@@ -85,26 +113,48 @@ func NewChannelzStorage() {
 		subChannels:      make(map[int64]*subChannel),
 	})
 	idGen.reset()
+	return func() error {
+		var err error
+		cm := db.get()
+		if cm == nil {
+			return nil
+		}
+		for i := 0; i < 1000; i++ {
+			cm.mu.Lock()
+			if len(cm.topLevelChannels) == 0 && len(cm.servers) == 0 && len(cm.channels) == 0 && len(cm.subChannels) == 0 && len(cm.listenSockets) == 0 && len(cm.normalSockets) == 0 {
+				cm.mu.Unlock()
+				// all things stored in the channelz map have been cleared.
+				return nil
+			}
+			cm.mu.Unlock()
+			time.Sleep(10 * time.Millisecond)
+		}
+
+		cm.mu.Lock()
+		err = fmt.Errorf("after 10s the channelz map has not been cleaned up yet, topchannels: %d, servers: %d, channels: %d, subchannels: %d, listen sockets: %d, normal sockets: %d", len(cm.topLevelChannels), len(cm.servers), len(cm.channels), len(cm.subChannels), len(cm.listenSockets), len(cm.normalSockets))
+		cm.mu.Unlock()
+		return err
+	}
 }
 
 // GetTopChannels returns a slice of top channel's ChannelMetric, along with a
 // boolean indicating whether there's more top channels to be queried for.
 //
 // The arg id specifies that only top channel with id at or above it will be included
-// in the result. The returned slice is up to a length of EntryPerPage, and is
-// sorted in ascending id order.
-func GetTopChannels(id int64) ([]*ChannelMetric, bool) {
-	return db.get().GetTopChannels(id)
+// in the result. The returned slice is up to a length of the arg maxResults or
+// EntryPerPage if maxResults is zero, and is sorted in ascending id order.
+func GetTopChannels(id int64, maxResults int64) ([]*ChannelMetric, bool) {
+	return db.get().GetTopChannels(id, maxResults)
 }
 
 // GetServers returns a slice of server's ServerMetric, along with a
 // boolean indicating whether there's more servers to be queried for.
 //
 // The arg id specifies that only server with id at or above it will be included
-// in the result. The returned slice is up to a length of EntryPerPage, and is
-// sorted in ascending id order.
-func GetServers(id int64) ([]*ServerMetric, bool) {
-	return db.get().GetServers(id)
+// in the result. The returned slice is up to a length of the arg maxResults or
+// EntryPerPage if maxResults is zero, and is sorted in ascending id order.
+func GetServers(id int64, maxResults int64) ([]*ServerMetric, bool) {
+	return db.get().GetServers(id, maxResults)
 }
 
 // GetServerSockets returns a slice of server's (identified by id) normal socket's
@@ -112,10 +162,10 @@ func GetServers(id int64) ([]*ServerMetric, bool) {
 // be queried for.
 //
 // The arg startID specifies that only sockets with id at or above it will be
-// included in the result. The returned slice is up to a length of EntryPerPage,
-// and is sorted in ascending id order.
-func GetServerSockets(id int64, startID int64) ([]*SocketMetric, bool) {
-	return db.get().GetServerSockets(id, startID)
+// included in the result. The returned slice is up to a length of the arg maxResults
+// or EntryPerPage if maxResults is zero, and is sorted in ascending id order.
+func GetServerSockets(id int64, startID int64, maxResults int64) ([]*SocketMetric, bool) {
+	return db.get().GetServerSockets(id, startID, maxResults)
 }
 
 // GetChannel returns the ChannelMetric for the channel (identified by id).
@@ -133,6 +183,11 @@ func GetSocket(id int64) *SocketMetric {
 	return db.get().GetSocket(id)
 }
 
+// GetServer returns the ServerMetric for the server (identified by id).
+func GetServer(id int64) *ServerMetric {
+	return db.get().GetServer(id)
+}
+
 // RegisterChannel registers the given channel c in channelz database with ref
 // as its reference name, and add it to the child list of its parent (identified
 // by pid). pid = 0 means no parent. It returns the unique channelz tracking id
@@ -146,6 +201,7 @@ func RegisterChannel(c Channel, pid int64, ref string) int64 {
 		nestedChans: make(map[int64]string),
 		id:          id,
 		pid:         pid,
+		trace:       &channelTrace{createdTime: time.Now(), events: make([]*TraceEvent, 0, getMaxTraceEntry())},
 	}
 	if pid == 0 {
 		db.get().addChannel(id, cn, true, pid, ref)
@@ -170,6 +226,7 @@ func RegisterSubChannel(c Channel, pid int64, ref string) int64 {
 		sockets: make(map[int64]string),
 		id:      id,
 		pid:     pid,
+		trace:   &channelTrace{createdTime: time.Now(), events: make([]*TraceEvent, 0, getMaxTraceEntry())},
 	}
 	db.get().addSubChannel(id, sc, pid, ref)
 	return id
@@ -226,6 +283,24 @@ func RemoveEntry(id int64) {
 	db.get().removeEntry(id)
 }
 
+// TraceEventDesc is what the caller of AddTraceEvent should provide to describe the event to be added
+// to the channel trace.
+// The Parent field is optional. It is used for event that will be recorded in the entity's parent
+// trace also.
+type TraceEventDesc struct {
+	Desc     string
+	Severity Severity
+	Parent   *TraceEventDesc
+}
+
+// AddTraceEvent adds trace related to the entity with specified id, using the provided TraceEventDesc.
+func AddTraceEvent(id int64, desc *TraceEventDesc) {
+	if getMaxTraceEntry() == 0 {
+		return
+	}
+	db.get().traceEvent(id, desc)
+}
+
 // channelMap is the storage data structure for channelz.
 // Methods of channelMap can be divided in two two categories with respect to locking.
 // 1. Methods acquire the global lock.
@@ -251,6 +326,7 @@ func (c *channelMap) addServer(id int64, s *server) {
 func (c *channelMap) addChannel(id int64, cn *channel, isTopChannel bool, pid int64, ref string) {
 	c.mu.Lock()
 	cn.cm = c
+	cn.trace.cm = c
 	c.channels[id] = cn
 	if isTopChannel {
 		c.topLevelChannels[id] = struct{}{}
@@ -263,6 +339,7 @@ func (c *channelMap) addChannel(id int64, cn *channel, isTopChannel bool, pid in
 func (c *channelMap) addSubChannel(id int64, sc *subChannel, pid int64, ref string) {
 	c.mu.Lock()
 	sc.cm = c
+	sc.trace.cm = c
 	c.subChannels[id] = sc
 	c.findEntry(pid).addChild(id, sc)
 	c.mu.Unlock()
@@ -284,16 +361,25 @@ func (c *channelMap) addNormalSocket(id int64, ns *normalSocket, pid int64, ref
 	c.mu.Unlock()
 }
 
-// removeEntry triggers the removal of an entry, which may not indeed delete the
-// entry, if it has to wait on the deletion of its children, or may lead to a chain
-// of entry deletion. For example, deleting the last socket of a gracefully shutting
-// down server will lead to the server being also deleted.
+// removeEntry triggers the removal of an entry, which may not indeed delete the entry, if it has to
+// wait on the deletion of its children and until no other entity's channel trace references it.
+// It may lead to a chain of entry deletion. For example, deleting the last socket of a gracefully
+// shutting down server will lead to the server being also deleted.
 func (c *channelMap) removeEntry(id int64) {
 	c.mu.Lock()
 	c.findEntry(id).triggerDelete()
 	c.mu.Unlock()
 }
 
+// c.mu must be held by the caller
+func (c *channelMap) decrTraceRefCount(id int64) {
+	e := c.findEntry(id)
+	if v, ok := e.(tracedChannel); ok {
+		v.decrTraceRefCount()
+		e.deleteSelfIfReady()
+	}
+}
+
 // c.mu must be held by the caller.
 func (c *channelMap) findEntry(id int64) entry {
 	var v entry
@@ -347,6 +433,39 @@ func (c *channelMap) deleteEntry(id int64) {
 	}
 }
 
+func (c *channelMap) traceEvent(id int64, desc *TraceEventDesc) {
+	c.mu.Lock()
+	child := c.findEntry(id)
+	childTC, ok := child.(tracedChannel)
+	if !ok {
+		c.mu.Unlock()
+		return
+	}
+	childTC.getChannelTrace().append(&TraceEvent{Desc: desc.Desc, Severity: desc.Severity, Timestamp: time.Now()})
+	if desc.Parent != nil {
+		parent := c.findEntry(child.getParentID())
+		var chanType RefChannelType
+		switch child.(type) {
+		case *channel:
+			chanType = RefChannel
+		case *subChannel:
+			chanType = RefSubChannel
+		}
+		if parentTC, ok := parent.(tracedChannel); ok {
+			parentTC.getChannelTrace().append(&TraceEvent{
+				Desc:      desc.Parent.Desc,
+				Severity:  desc.Parent.Severity,
+				Timestamp: time.Now(),
+				RefID:     id,
+				RefName:   childTC.getRefName(),
+				RefType:   chanType,
+			})
+			childTC.incrTraceRefCount()
+		}
+	}
+	c.mu.Unlock()
+}
+
 type int64Slice []int64
 
 func (s int64Slice) Len() int           { return len(s) }
@@ -361,29 +480,32 @@ func copyMap(m map[int64]string) map[int64]string {
 	return n
 }
 
-func min(a, b int) int {
+func min(a, b int64) int64 {
 	if a < b {
 		return a
 	}
 	return b
 }
 
-func (c *channelMap) GetTopChannels(id int64) ([]*ChannelMetric, bool) {
+func (c *channelMap) GetTopChannels(id int64, maxResults int64) ([]*ChannelMetric, bool) {
+	if maxResults <= 0 {
+		maxResults = EntryPerPage
+	}
 	c.mu.RLock()
-	l := len(c.topLevelChannels)
+	l := int64(len(c.topLevelChannels))
 	ids := make([]int64, 0, l)
-	cns := make([]*channel, 0, min(l, EntryPerPage))
+	cns := make([]*channel, 0, min(l, maxResults))
 
 	for k := range c.topLevelChannels {
 		ids = append(ids, k)
 	}
 	sort.Sort(int64Slice(ids))
 	idx := sort.Search(len(ids), func(i int) bool { return ids[i] >= id })
-	count := 0
+	count := int64(0)
 	var end bool
 	var t []*ChannelMetric
 	for i, v := range ids[idx:] {
-		if count == EntryPerPage {
+		if count == maxResults {
 			break
 		}
 		if cn, ok := c.channels[v]; ok {
@@ -408,25 +530,29 @@ func (c *channelMap) GetTopChannels(id int64) ([]*ChannelMetric, bool) {
 		t[i].ChannelData = cn.c.ChannelzMetric()
 		t[i].ID = cn.id
 		t[i].RefName = cn.refName
+		t[i].Trace = cn.trace.dumpData()
 	}
 	return t, end
 }
 
-func (c *channelMap) GetServers(id int64) ([]*ServerMetric, bool) {
+func (c *channelMap) GetServers(id, maxResults int64) ([]*ServerMetric, bool) {
+	if maxResults <= 0 {
+		maxResults = EntryPerPage
+	}
 	c.mu.RLock()
-	l := len(c.servers)
+	l := int64(len(c.servers))
 	ids := make([]int64, 0, l)
-	ss := make([]*server, 0, min(l, EntryPerPage))
+	ss := make([]*server, 0, min(l, maxResults))
 	for k := range c.servers {
 		ids = append(ids, k)
 	}
 	sort.Sort(int64Slice(ids))
 	idx := sort.Search(len(ids), func(i int) bool { return ids[i] >= id })
-	count := 0
+	count := int64(0)
 	var end bool
 	var s []*ServerMetric
 	for i, v := range ids[idx:] {
-		if count == EntryPerPage {
+		if count == maxResults {
 			break
 		}
 		if svr, ok := c.servers[v]; ok {
@@ -454,7 +580,10 @@ func (c *channelMap) GetServers(id int64) ([]*ServerMetric, bool) {
 	return s, end
 }
 
-func (c *channelMap) GetServerSockets(id int64, startID int64) ([]*SocketMetric, bool) {
+func (c *channelMap) GetServerSockets(id int64, startID int64, maxResults int64) ([]*SocketMetric, bool) {
+	if maxResults <= 0 {
+		maxResults = EntryPerPage
+	}
 	var svr *server
 	var ok bool
 	c.mu.RLock()
@@ -464,18 +593,18 @@ func (c *channelMap) GetServerSockets(id int64, startID int64) ([]*SocketMetric,
 		return nil, true
 	}
 	svrskts := svr.sockets
-	l := len(svrskts)
+	l := int64(len(svrskts))
 	ids := make([]int64, 0, l)
-	sks := make([]*normalSocket, 0, min(l, EntryPerPage))
+	sks := make([]*normalSocket, 0, min(l, maxResults))
 	for k := range svrskts {
 		ids = append(ids, k)
 	}
-	sort.Sort((int64Slice(ids)))
-	idx := sort.Search(len(ids), func(i int) bool { return ids[i] >= id })
-	count := 0
+	sort.Sort(int64Slice(ids))
+	idx := sort.Search(len(ids), func(i int) bool { return ids[i] >= startID })
+	count := int64(0)
 	var end bool
 	for i, v := range ids[idx:] {
-		if count == EntryPerPage {
+		if count == maxResults {
 			break
 		}
 		if ns, ok := c.normalSockets[v]; ok {
@@ -514,10 +643,14 @@ func (c *channelMap) GetChannel(id int64) *ChannelMetric {
 	}
 	cm.NestedChans = copyMap(cn.nestedChans)
 	cm.SubChans = copyMap(cn.subChans)
+	// cn.c can be set to &dummyChannel{} when deleteSelfFromMap is called. Save a copy of cn.c when
+	// holding the lock to prevent potential data race.
+	chanCopy := cn.c
 	c.mu.RUnlock()
-	cm.ChannelData = cn.c.ChannelzMetric()
+	cm.ChannelData = chanCopy.ChannelzMetric()
 	cm.ID = cn.id
 	cm.RefName = cn.refName
+	cm.Trace = cn.trace.dumpData()
 	return cm
 }
 
@@ -532,10 +665,14 @@ func (c *channelMap) GetSubChannel(id int64) *SubChannelMetric {
 		return nil
 	}
 	cm.Sockets = copyMap(sc.sockets)
+	// sc.c can be set to &dummyChannel{} when deleteSelfFromMap is called. Save a copy of sc.c when
+	// holding the lock to prevent potential data race.
+	chanCopy := sc.c
 	c.mu.RUnlock()
-	cm.ChannelData = sc.c.ChannelzMetric()
+	cm.ChannelData = chanCopy.ChannelzMetric()
 	cm.ID = sc.id
 	cm.RefName = sc.refName
+	cm.Trace = sc.trace.dumpData()
 	return cm
 }
 
@@ -560,6 +697,23 @@ func (c *channelMap) GetSocket(id int64) *SocketMetric {
 	return nil
 }
 
+func (c *channelMap) GetServer(id int64) *ServerMetric {
+	sm := &ServerMetric{}
+	var svr *server
+	var ok bool
+	c.mu.RLock()
+	if svr, ok = c.servers[id]; !ok {
+		c.mu.RUnlock()
+		return nil
+	}
+	sm.ListenSockets = copyMap(svr.listenSockets)
+	c.mu.RUnlock()
+	sm.ID = svr.id
+	sm.RefName = svr.refName
+	sm.ServerData = svr.s.ChannelzMetric()
+	return sm
+}
+
 type idGenerator struct {
 	id int64
 }
diff --git a/vendor/google.golang.org/grpc/internal/channelz/types.go b/vendor/google.golang.org/grpc/internal/channelz/types.go
index 6fd6bb38..17c2274c 100644
--- a/vendor/google.golang.org/grpc/internal/channelz/types.go
+++ b/vendor/google.golang.org/grpc/internal/channelz/types.go
@@ -20,6 +20,8 @@ package channelz
 
 import (
 	"net"
+	"sync"
+	"sync/atomic"
 	"time"
 
 	"google.golang.org/grpc/connectivity"
@@ -40,6 +42,8 @@ type entry interface {
 	// deleteSelfIfReady check whether triggerDelete() has been called before, and whether child
 	// list is now empty. If both conditions are met, then delete self from database.
 	deleteSelfIfReady()
+	// getParentID returns parent ID of the entry. 0 value parent ID means no parent.
+	getParentID() int64
 }
 
 // dummyEntry is a fake entry to handle entry not found case.
@@ -73,6 +77,10 @@ func (*dummyEntry) deleteSelfIfReady() {
 	// code should not reach here. deleteSelfIfReady is always called on an existing entry.
 }
 
+func (*dummyEntry) getParentID() int64 {
+	return 0
+}
+
 // ChannelMetric defines the info channelz provides for a specific Channel, which
 // includes ChannelInternalMetric and channelz-specific data, such as channelz id,
 // child list, etc.
@@ -95,6 +103,8 @@ type ChannelMetric struct {
 	// Note current grpc implementation doesn't allow channel having sockets directly,
 	// therefore, this is field is unused.
 	Sockets map[int64]string
+	// Trace contains the most recent traced events.
+	Trace *ChannelTrace
 }
 
 // SubChannelMetric defines the info channelz provides for a specific SubChannel,
@@ -121,6 +131,8 @@ type SubChannelMetric struct {
 	// Sockets tracks the socket type children of this subchannel in the format of a map
 	// from socket channelz id to corresponding reference string.
 	Sockets map[int64]string
+	// Trace contains the most recent traced events.
+	Trace *ChannelTrace
 }
 
 // ChannelInternalMetric defines the struct that the implementor of Channel interface
@@ -138,7 +150,35 @@ type ChannelInternalMetric struct {
 	CallsFailed int64
 	// The last time a call was started on the channel.
 	LastCallStartedTimestamp time.Time
-	//TODO: trace
+}
+
+// ChannelTrace stores traced events on a channel/subchannel and related info.
+type ChannelTrace struct {
+	// EventNum is the number of events that ever got traced (i.e. including those that have been deleted)
+	EventNum int64
+	// CreationTime is the creation time of the trace.
+	CreationTime time.Time
+	// Events stores the most recent trace events (up to $maxTraceEntry, newer event will overwrite the
+	// oldest one)
+	Events []*TraceEvent
+}
+
+// TraceEvent represent a single trace event
+type TraceEvent struct {
+	// Desc is a simple description of the trace event.
+	Desc string
+	// Severity states the severity of this trace event.
+	Severity Severity
+	// Timestamp is the event time.
+	Timestamp time.Time
+	// RefID is the id of the entity that gets referenced in the event. RefID is 0 if no other entity is
+	// involved in this event.
+	// e.g. SubChannel (id: 4[]) Created. --> RefID = 4, RefName = "" (inside [])
+	RefID int64
+	// RefName is the reference name for the entity that gets referenced in the event.
+	RefName string
+	// RefType indicates the referenced entity type, i.e Channel or SubChannel.
+	RefType RefChannelType
 }
 
 // Channel is the interface that should be satisfied in order to be tracked by
@@ -147,6 +187,12 @@ type Channel interface {
 	ChannelzMetric() *ChannelInternalMetric
 }
 
+type dummyChannel struct{}
+
+func (d *dummyChannel) ChannelzMetric() *ChannelInternalMetric {
+	return &ChannelInternalMetric{}
+}
+
 type channel struct {
 	refName     string
 	c           Channel
@@ -156,6 +202,10 @@ type channel struct {
 	id          int64
 	pid         int64
 	cm          *channelMap
+	trace       *channelTrace
+	// traceRefCount is the number of trace events that reference this channel.
+	// Non-zero traceRefCount means the trace of this channel cannot be deleted.
+	traceRefCount int32
 }
 
 func (c *channel) addChild(id int64, e entry) {
@@ -180,25 +230,96 @@ func (c *channel) triggerDelete() {
 	c.deleteSelfIfReady()
 }
 
-func (c *channel) deleteSelfIfReady() {
+func (c *channel) getParentID() int64 {
+	return c.pid
+}
+
+// deleteSelfFromTree tries to delete the channel from the channelz entry relation tree, which means
+// deleting the channel reference from its parent's child list.
+//
+// In order for a channel to be deleted from the tree, it must meet the criteria that, removal of the
+// corresponding grpc object has been invoked, and the channel does not have any children left.
+//
+// The returned boolean value indicates whether the channel has been successfully deleted from tree.
+func (c *channel) deleteSelfFromTree() (deleted bool) {
 	if !c.closeCalled || len(c.subChans)+len(c.nestedChans) != 0 {
-		return
+		return false
 	}
-	c.cm.deleteEntry(c.id)
 	// not top channel
 	if c.pid != 0 {
 		c.cm.findEntry(c.pid).deleteChild(c.id)
 	}
+	return true
+}
+
+// deleteSelfFromMap checks whether it is valid to delete the channel from the map, which means
+// deleting the channel from channelz's tracking entirely. Users can no longer use id to query the
+// channel, and its memory will be garbage collected.
+//
+// The trace reference count of the channel must be 0 in order to be deleted from the map. This is
+// specified in the channel tracing gRFC that as long as some other trace has reference to an entity,
+// the trace of the referenced entity must not be deleted. In order to release the resource allocated
+// by grpc, the reference to the grpc object is reset to a dummy object.
+//
+// deleteSelfFromMap must be called after deleteSelfFromTree returns true.
+//
+// It returns a bool to indicate whether the channel can be safely deleted from map.
+func (c *channel) deleteSelfFromMap() (delete bool) {
+	if c.getTraceRefCount() != 0 {
+		c.c = &dummyChannel{}
+		return false
+	}
+	return true
+}
+
+// deleteSelfIfReady tries to delete the channel itself from the channelz database.
+// The delete process includes two steps:
+// 1. delete the channel from the entry relation tree, i.e. delete the channel reference from its
+//    parent's child list.
+// 2. delete the channel from the map, i.e. delete the channel entirely from channelz. Lookup by id
+//    will return entry not found error.
+func (c *channel) deleteSelfIfReady() {
+	if !c.deleteSelfFromTree() {
+		return
+	}
+	if !c.deleteSelfFromMap() {
+		return
+	}
+	c.cm.deleteEntry(c.id)
+	c.trace.clear()
+}
+
+func (c *channel) getChannelTrace() *channelTrace {
+	return c.trace
+}
+
+func (c *channel) incrTraceRefCount() {
+	atomic.AddInt32(&c.traceRefCount, 1)
+}
+
+func (c *channel) decrTraceRefCount() {
+	atomic.AddInt32(&c.traceRefCount, -1)
+}
+
+func (c *channel) getTraceRefCount() int {
+	i := atomic.LoadInt32(&c.traceRefCount)
+	return int(i)
+}
+
+func (c *channel) getRefName() string {
+	return c.refName
 }
 
 type subChannel struct {
-	refName     string
-	c           Channel
-	closeCalled bool
-	sockets     map[int64]string
-	id          int64
-	pid         int64
-	cm          *channelMap
+	refName       string
+	c             Channel
+	closeCalled   bool
+	sockets       map[int64]string
+	id            int64
+	pid           int64
+	cm            *channelMap
+	trace         *channelTrace
+	traceRefCount int32
 }
 
 func (sc *subChannel) addChild(id int64, e entry) {
@@ -219,12 +340,82 @@ func (sc *subChannel) triggerDelete() {
 	sc.deleteSelfIfReady()
 }
 
-func (sc *subChannel) deleteSelfIfReady() {
+func (sc *subChannel) getParentID() int64 {
+	return sc.pid
+}
+
+// deleteSelfFromTree tries to delete the subchannel from the channelz entry relation tree, which
+// means deleting the subchannel reference from its parent's child list.
+//
+// In order for a subchannel to be deleted from the tree, it must meet the criteria that, removal of
+// the corresponding grpc object has been invoked, and the subchannel does not have any children left.
+//
+// The returned boolean value indicates whether the channel has been successfully deleted from tree.
+func (sc *subChannel) deleteSelfFromTree() (deleted bool) {
 	if !sc.closeCalled || len(sc.sockets) != 0 {
+		return false
+	}
+	sc.cm.findEntry(sc.pid).deleteChild(sc.id)
+	return true
+}
+
+// deleteSelfFromMap checks whether it is valid to delete the subchannel from the map, which means
+// deleting the subchannel from channelz's tracking entirely. Users can no longer use id to query
+// the subchannel, and its memory will be garbage collected.
+//
+// The trace reference count of the subchannel must be 0 in order to be deleted from the map. This is
+// specified in the channel tracing gRFC that as long as some other trace has reference to an entity,
+// the trace of the referenced entity must not be deleted. In order to release the resource allocated
+// by grpc, the reference to the grpc object is reset to a dummy object.
+//
+// deleteSelfFromMap must be called after deleteSelfFromTree returns true.
+//
+// It returns a bool to indicate whether the channel can be safely deleted from map.
+func (sc *subChannel) deleteSelfFromMap() (delete bool) {
+	if sc.getTraceRefCount() != 0 {
+		// free the grpc struct (i.e. addrConn)
+		sc.c = &dummyChannel{}
+		return false
+	}
+	return true
+}
+
+// deleteSelfIfReady tries to delete the subchannel itself from the channelz database.
+// The delete process includes two steps:
+// 1. delete the subchannel from the entry relation tree, i.e. delete the subchannel reference from
+//    its parent's child list.
+// 2. delete the subchannel from the map, i.e. delete the subchannel entirely from channelz. Lookup
+//    by id will return entry not found error.
+func (sc *subChannel) deleteSelfIfReady() {
+	if !sc.deleteSelfFromTree() {
+		return
+	}
+	if !sc.deleteSelfFromMap() {
 		return
 	}
 	sc.cm.deleteEntry(sc.id)
-	sc.cm.findEntry(sc.pid).deleteChild(sc.id)
+	sc.trace.clear()
+}
+
+func (sc *subChannel) getChannelTrace() *channelTrace {
+	return sc.trace
+}
+
+func (sc *subChannel) incrTraceRefCount() {
+	atomic.AddInt32(&sc.traceRefCount, 1)
+}
+
+func (sc *subChannel) decrTraceRefCount() {
+	atomic.AddInt32(&sc.traceRefCount, -1)
+}
+
+func (sc *subChannel) getTraceRefCount() int {
+	i := atomic.LoadInt32(&sc.traceRefCount)
+	return int(i)
+}
+
+func (sc *subChannel) getRefName() string {
+	return sc.refName
 }
 
 // SocketMetric defines the info channelz provides for a specific Socket, which
@@ -318,6 +509,10 @@ func (ls *listenSocket) deleteSelfIfReady() {
 	grpclog.Errorf("cannot call deleteSelfIfReady on a listen socket")
 }
 
+func (ls *listenSocket) getParentID() int64 {
+	return ls.pid
+}
+
 type normalSocket struct {
 	refName string
 	s       Socket
@@ -343,6 +538,10 @@ func (ns *normalSocket) deleteSelfIfReady() {
 	grpclog.Errorf("cannot call deleteSelfIfReady on a normal socket")
 }
 
+func (ns *normalSocket) getParentID() int64 {
+	return ns.pid
+}
+
 // ServerMetric defines the info channelz provides for a specific Server, which
 // includes ServerInternalMetric and channelz-specific data, such as channelz id,
 // child list, etc.
@@ -370,7 +569,6 @@ type ServerInternalMetric struct {
 	CallsFailed int64
 	// The last time a call was started on the server.
 	LastCallStartedTimestamp time.Time
-	//TODO: trace
 }
 
 // Server is the interface to be satisfied in order to be tracked by channelz as
@@ -417,3 +615,88 @@ func (s *server) deleteSelfIfReady() {
 	}
 	s.cm.deleteEntry(s.id)
 }
+
+func (s *server) getParentID() int64 {
+	return 0
+}
+
+type tracedChannel interface {
+	getChannelTrace() *channelTrace
+	incrTraceRefCount()
+	decrTraceRefCount()
+	getRefName() string
+}
+
+type channelTrace struct {
+	cm          *channelMap
+	createdTime time.Time
+	eventCount  int64
+	mu          sync.Mutex
+	events      []*TraceEvent
+}
+
+func (c *channelTrace) append(e *TraceEvent) {
+	c.mu.Lock()
+	if len(c.events) == getMaxTraceEntry() {
+		del := c.events[0]
+		c.events = c.events[1:]
+		if del.RefID != 0 {
+			// start recursive cleanup in a goroutine to not block the call originated from grpc.
+			go func() {
+				// need to acquire c.cm.mu lock to call the unlocked attemptCleanup func.
+				c.cm.mu.Lock()
+				c.cm.decrTraceRefCount(del.RefID)
+				c.cm.mu.Unlock()
+			}()
+		}
+	}
+	e.Timestamp = time.Now()
+	c.events = append(c.events, e)
+	c.eventCount++
+	c.mu.Unlock()
+}
+
+func (c *channelTrace) clear() {
+	c.mu.Lock()
+	for _, e := range c.events {
+		if e.RefID != 0 {
+			// caller should have already held the c.cm.mu lock.
+			c.cm.decrTraceRefCount(e.RefID)
+		}
+	}
+	c.mu.Unlock()
+}
+
+// Severity is the severity level of a trace event.
+// The canonical enumeration of all valid values is here:
+// https://github.com/grpc/grpc-proto/blob/9b13d199cc0d4703c7ea26c9c330ba695866eb23/grpc/channelz/v1/channelz.proto#L126.
+type Severity int
+
+const (
+	// CtUNKNOWN indicates unknown severity of a trace event.
+	CtUNKNOWN Severity = iota
+	// CtINFO indicates info level severity of a trace event.
+	CtINFO
+	// CtWarning indicates warning level severity of a trace event.
+	CtWarning
+	// CtError indicates error level severity of a trace event.
+	CtError
+)
+
+// RefChannelType is the type of the entity being referenced in a trace event.
+type RefChannelType int
+
+const (
+	// RefChannel indicates the referenced entity is a Channel.
+	RefChannel RefChannelType = iota
+	// RefSubChannel indicates the referenced entity is a SubChannel.
+	RefSubChannel
+)
+
+func (c *channelTrace) dumpData() *ChannelTrace {
+	c.mu.Lock()
+	ct := &ChannelTrace{EventNum: c.eventCount, CreationTime: c.createdTime}
+	ct.Events = c.events[:len(c.events)]
+	c.mu.Unlock()
+	return ct
+}
diff --git a/vendor/google.golang.org/grpc/internal/channelz/types_linux.go b/vendor/google.golang.org/grpc/internal/channelz/types_linux.go
index 9801c3e2..692dd618 100644
--- a/vendor/google.golang.org/grpc/internal/channelz/types_linux.go
+++ b/vendor/google.golang.org/grpc/internal/channelz/types_linux.go
@@ -1,4 +1,4 @@
-// +build !appengine,go1.7
+// +build !appengine
 
 /*
  *
@@ -50,5 +50,4 @@ func (s *SocketOptionData) Getsockopt(fd uintptr) {
 	if v, err := unix.GetsockoptTCPInfo(int(fd), syscall.SOL_TCP, syscall.TCP_INFO); err == nil {
 		s.TCPInfo = v
 	}
-	return
 }
diff --git a/vendor/google.golang.org/grpc/internal/channelz/types_nonlinux.go b/vendor/google.golang.org/grpc/internal/channelz/types_nonlinux.go
index 884910c4..79edbefc 100644
--- a/vendor/google.golang.org/grpc/internal/channelz/types_nonlinux.go
+++ b/vendor/google.golang.org/grpc/internal/channelz/types_nonlinux.go
@@ -1,4 +1,4 @@
-// +build !linux appengine !go1.7
+// +build !linux appengine
 
 /*
  *
@@ -20,11 +20,13 @@
 
 package channelz
 
-import "google.golang.org/grpc/grpclog"
+import (
+	"sync"
 
-func init() {
-	grpclog.Infof("Channelz: socket options are not supported on non-linux os and appengine.")
-}
+	"google.golang.org/grpc/grpclog"
+)
+
+var once sync.Once
 
 // SocketOptionData defines the struct to hold socket option data, and related
 // getter function to obtain info from fd.
@@ -35,4 +37,8 @@ type SocketOptionData struct {
 // Getsockopt defines the function to get socket options requested by channelz.
 // It is to be passed to syscall.RawConn.Control().
 // Windows OS doesn't support Socket Option
-func (s *SocketOptionData) Getsockopt(fd uintptr) {}
+func (s *SocketOptionData) Getsockopt(fd uintptr) {
+	once.Do(func() {
+		grpclog.Warningln("Channelz: socket options are not supported on non-linux os and appengine.")
+	})
+}
diff --git a/vendor/google.golang.org/grpc/internal/channelz/util_linux_go19.go b/vendor/google.golang.org/grpc/internal/channelz/util_linux.go
similarity index 96%
rename from vendor/google.golang.org/grpc/internal/channelz/util_linux_go19.go
rename to vendor/google.golang.org/grpc/internal/channelz/util_linux.go
index e1e9e32d..fdf409d5 100644
--- a/vendor/google.golang.org/grpc/internal/channelz/util_linux_go19.go
+++ b/vendor/google.golang.org/grpc/internal/channelz/util_linux.go
@@ -1,4 +1,4 @@
-// +build linux,go1.9,!appengine
+// +build linux,!appengine
 
 /*
  *
diff --git a/vendor/google.golang.org/grpc/internal/channelz/util_nonlinux_pre_go19.go b/vendor/google.golang.org/grpc/internal/channelz/util_nonlinux.go
similarity index 95%
rename from vendor/google.golang.org/grpc/internal/channelz/util_nonlinux_pre_go19.go
rename to vendor/google.golang.org/grpc/internal/channelz/util_nonlinux.go
index 1d4da952..8864a081 100644
--- a/vendor/google.golang.org/grpc/internal/channelz/util_nonlinux_pre_go19.go
+++ b/vendor/google.golang.org/grpc/internal/channelz/util_nonlinux.go
@@ -1,4 +1,4 @@
-// +build !linux !go1.9 appengine
+// +build !linux appengine
 
 /*
  *
diff --git a/vendor/google.golang.org/grpc/internal/grpcsync/event.go b/vendor/google.golang.org/grpc/internal/grpcsync/event.go
new file mode 100644
index 00000000..fbe697c3
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/grpcsync/event.go
@@ -0,0 +1,61 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package grpcsync implements additional synchronization primitives built upon
+// the sync package.
+package grpcsync
+
+import (
+	"sync"
+	"sync/atomic"
+)
+
+// Event represents a one-time event that may occur in the future.
+type Event struct {
+	fired int32
+	c     chan struct{}
+	o     sync.Once
+}
+
+// Fire causes e to complete.  It is safe to call multiple times, and
+// concurrently.  It returns true iff this call to Fire caused the signaling
+// channel returned by Done to close.
+func (e *Event) Fire() bool {
+	ret := false
+	e.o.Do(func() {
+		atomic.StoreInt32(&e.fired, 1)
+		close(e.c)
+		ret = true
+	})
+	return ret
+}
+
+// Done returns a channel that will be closed when Fire is called.
+func (e *Event) Done() <-chan struct{} {
+	return e.c
+}
+
+// HasFired returns true if Fire has been called.
+func (e *Event) HasFired() bool {
+	return atomic.LoadInt32(&e.fired) == 1
+}
+
+// NewEvent returns a new, ready-to-use Event.
+func NewEvent() *Event {
+	return &Event{c: make(chan struct{})}
+}
diff --git a/vendor/google.golang.org/grpc/internal/internal.go b/vendor/google.golang.org/grpc/internal/internal.go
index cd34267f..bc1f99ac 100644
--- a/vendor/google.golang.org/grpc/internal/internal.go
+++ b/vendor/google.golang.org/grpc/internal/internal.go
@@ -20,17 +20,52 @@
 // symbols to avoid circular dependencies.
 package internal
 
-var (
+import (
+	"context"
+	"time"
 
-	// TestingUseHandlerImpl enables the http.Handler-based server implementation.
-	// It must be called before Serve and requires TLS credentials.
-	//
-	// The provided grpcServer must be of type *grpc.Server. It is untyped
-	// for circular dependency reasons.
-	TestingUseHandlerImpl func(grpcServer interface{})
+	"google.golang.org/grpc/connectivity"
+)
 
-	// WithContextDialer is exported by clientconn.go
-	WithContextDialer interface{} // func(context.Context, string) (net.Conn, error) grpc.DialOption
-	// WithResolverBuilder is exported by clientconn.go
+var (
+	// WithResolverBuilder is exported by dialoptions.go
 	WithResolverBuilder interface{} // func (resolver.Builder) grpc.DialOption
+	// WithHealthCheckFunc is not exported by dialoptions.go
+	WithHealthCheckFunc interface{} // func (HealthChecker) DialOption
+	// HealthCheckFunc is used to provide client-side LB channel health checking
+	HealthCheckFunc HealthChecker
+	// BalancerUnregister is exported by package balancer to unregister a balancer.
+	BalancerUnregister func(name string)
+	// KeepaliveMinPingTime is the minimum ping interval.  This must be 10s by
+	// default, but tests may wish to set it lower for convenience.
+	KeepaliveMinPingTime = 10 * time.Second
+	// ParseServiceConfig is a function to parse JSON service configs into
+	// opaque data structures.
+	ParseServiceConfig func(sc string) (interface{}, error)
+	// StatusRawProto is exported by status/status.go. This func returns a
+	// pointer to the wrapped Status proto for a given status.Status without a
+	// call to proto.Clone(). The returned Status proto should not be mutated by
+	// the caller.
+	StatusRawProto interface{} // func (*status.Status) *spb.Status
+)
+
+// HealthChecker defines the signature of the client-side LB channel health checking function.
+//
+// The implementation is expected to create a health checking RPC stream by
+// calling newStream(), watch for the health status of serviceName, and report
+// it's health back by calling setConnectivityState().
+//
+// The health checking protocol is defined at:
+// https://github.com/grpc/grpc/blob/master/doc/health-checking.md
+type HealthChecker func(ctx context.Context, newStream func(string) (interface{}, error), setConnectivityState func(connectivity.State), serviceName string) error
+
+const (
+	// CredsBundleModeFallback switches GoogleDefaultCreds to fallback mode.
+	CredsBundleModeFallback = "fallback"
+	// CredsBundleModeBalancer switches GoogleDefaultCreds to grpclb balancer
+	// mode.
+	CredsBundleModeBalancer = "balancer"
+	// CredsBundleModeBackendFromBalancer switches GoogleDefaultCreds to mode
+	// that supports backend returned by grpclb balancer.
+	CredsBundleModeBackendFromBalancer = "backend-from-balancer"
 )
diff --git a/vendor/google.golang.org/grpc/internal/syscall/syscall_linux.go b/vendor/google.golang.org/grpc/internal/syscall/syscall_linux.go
new file mode 100644
index 00000000..43281a3e
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/syscall/syscall_linux.go
@@ -0,0 +1,114 @@
+// +build !appengine
+
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package syscall provides functionalities that grpc uses to get low-level operating system
+// stats/info.
+package syscall
+
+import (
+	"fmt"
+	"net"
+	"syscall"
+	"time"
+
+	"golang.org/x/sys/unix"
+	"google.golang.org/grpc/grpclog"
+)
+
+// GetCPUTime returns the how much CPU time has passed since the start of this process.
+func GetCPUTime() int64 {
+	var ts unix.Timespec
+	if err := unix.ClockGettime(unix.CLOCK_PROCESS_CPUTIME_ID, &ts); err != nil {
+		grpclog.Fatal(err)
+	}
+	return ts.Nano()
+}
+
+// Rusage is an alias for syscall.Rusage under linux non-appengine environment.
+type Rusage syscall.Rusage
+
+// GetRusage returns the resource usage of current process.
+func GetRusage() (rusage *Rusage) {
+	rusage = new(Rusage)
+	syscall.Getrusage(syscall.RUSAGE_SELF, (*syscall.Rusage)(rusage))
+	return
+}
+
+// CPUTimeDiff returns the differences of user CPU time and system CPU time used
+// between two Rusage structs.
+func CPUTimeDiff(first *Rusage, latest *Rusage) (float64, float64) {
+	f := (*syscall.Rusage)(first)
+	l := (*syscall.Rusage)(latest)
+	var (
+		utimeDiffs  = l.Utime.Sec - f.Utime.Sec
+		utimeDiffus = l.Utime.Usec - f.Utime.Usec
+		stimeDiffs  = l.Stime.Sec - f.Stime.Sec
+		stimeDiffus = l.Stime.Usec - f.Stime.Usec
+	)
+
+	uTimeElapsed := float64(utimeDiffs) + float64(utimeDiffus)*1.0e-6
+	sTimeElapsed := float64(stimeDiffs) + float64(stimeDiffus)*1.0e-6
+
+	return uTimeElapsed, sTimeElapsed
+}
+
+// SetTCPUserTimeout sets the TCP user timeout on a connection's socket
+func SetTCPUserTimeout(conn net.Conn, timeout time.Duration) error {
+	tcpconn, ok := conn.(*net.TCPConn)
+	if !ok {
+		// not a TCP connection. exit early
+		return nil
+	}
+	rawConn, err := tcpconn.SyscallConn()
+	if err != nil {
+		return fmt.Errorf("error getting raw connection: %v", err)
+	}
+	err = rawConn.Control(func(fd uintptr) {
+		err = syscall.SetsockoptInt(int(fd), syscall.IPPROTO_TCP, unix.TCP_USER_TIMEOUT, int(timeout/time.Millisecond))
+	})
+	if err != nil {
+		return fmt.Errorf("error setting option on socket: %v", err)
+	}
+
+	return nil
+}
+
+// GetTCPUserTimeout gets the TCP user timeout on a connection's socket
+func GetTCPUserTimeout(conn net.Conn) (opt int, err error) {
+	tcpconn, ok := conn.(*net.TCPConn)
+	if !ok {
+		err = fmt.Errorf("conn is not *net.TCPConn. got %T", conn)
+		return
+	}
+	rawConn, err := tcpconn.SyscallConn()
+	if err != nil {
+		err = fmt.Errorf("error getting raw connection: %v", err)
+		return
+	}
+	err = rawConn.Control(func(fd uintptr) {
+		opt, err = syscall.GetsockoptInt(int(fd), syscall.IPPROTO_TCP, unix.TCP_USER_TIMEOUT)
+	})
+	if err != nil {
+		err = fmt.Errorf("error getting option on socket: %v", err)
+		return
+	}
+
+	return
+}
diff --git a/vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go b/vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go
new file mode 100644
index 00000000..d3fd9dab
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go
@@ -0,0 +1,73 @@
+// +build !linux appengine
+
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package syscall
+
+import (
+	"net"
+	"sync"
+	"time"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+var once sync.Once
+
+func log() {
+	once.Do(func() {
+		grpclog.Info("CPU time info is unavailable on non-linux or appengine environment.")
+	})
+}
+
+// GetCPUTime returns the how much CPU time has passed since the start of this process.
+// It always returns 0 under non-linux or appengine environment.
+func GetCPUTime() int64 {
+	log()
+	return 0
+}
+
+// Rusage is an empty struct under non-linux or appengine environment.
+type Rusage struct{}
+
+// GetRusage is a no-op function under non-linux or appengine environment.
+func GetRusage() (rusage *Rusage) {
+	log()
+	return nil
+}
+
+// CPUTimeDiff returns the differences of user CPU time and system CPU time used
+// between two Rusage structs. It a no-op function for non-linux or appengine environment.
+func CPUTimeDiff(first *Rusage, latest *Rusage) (float64, float64) {
+	log()
+	return 0, 0
+}
+
+// SetTCPUserTimeout is a no-op function under non-linux or appengine environments
+func SetTCPUserTimeout(conn net.Conn, timeout time.Duration) error {
+	log()
+	return nil
+}
+
+// GetTCPUserTimeout is a no-op function under non-linux or appengine environments
+// a negative return value indicates the operation is not supported
+func GetTCPUserTimeout(conn net.Conn) (int, error) {
+	log()
+	return -1, nil
+}
diff --git a/vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go b/vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go
index 63cd2627..070680ed 100644
--- a/vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go
+++ b/vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go
@@ -24,9 +24,10 @@ import (
 )
 
 const (
-	// bdpLimit is the maximum value the flow control windows
-	// will be increased to.
-	bdpLimit = (1 << 20) * 4
+	// bdpLimit is the maximum value the flow control windows will be increased
+	// to.  TCP typically limits this to 4MB, but some systems go up to 16MB.
+	// Since this is only a limit, it is safe to make it optimistic.
+	bdpLimit = (1 << 20) * 16
 	// alpha is a constant factor used to keep a moving average
 	// of RTTs.
 	alpha = 0.9
diff --git a/vendor/google.golang.org/grpc/internal/transport/controlbuf.go b/vendor/google.golang.org/grpc/internal/transport/controlbuf.go
index ce135c4d..b8e0aa4d 100644
--- a/vendor/google.golang.org/grpc/internal/transport/controlbuf.go
+++ b/vendor/google.golang.org/grpc/internal/transport/controlbuf.go
@@ -23,6 +23,7 @@ import (
 	"fmt"
 	"runtime"
 	"sync"
+	"sync/atomic"
 
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
@@ -84,12 +85,24 @@ func (il *itemList) isEmpty() bool {
 // the control buffer of transport. They represent different aspects of
 // control tasks, e.g., flow control, settings, streaming resetting, etc.
 
+// maxQueuedTransportResponseFrames is the most queued "transport response"
+// frames we will buffer before preventing new reads from occurring on the
+// transport.  These are control frames sent in response to client requests,
+// such as RST_STREAM due to bad headers or settings acks.
+const maxQueuedTransportResponseFrames = 50
+
+type cbItem interface {
+	isTransportResponseFrame() bool
+}
+
 // registerStream is used to register an incoming stream with loopy writer.
 type registerStream struct {
 	streamID uint32
 	wq       *writeQuota
 }
 
+func (*registerStream) isTransportResponseFrame() bool { return false }
+
 // headerFrame is also used to register stream on the client-side.
 type headerFrame struct {
 	streamID   uint32
@@ -102,14 +115,19 @@ type headerFrame struct {
 	onOrphaned func(error)    // Valid on client-side
 }
 
+func (h *headerFrame) isTransportResponseFrame() bool {
+	return h.cleanup != nil && h.cleanup.rst // Results in a RST_STREAM
+}
+
 type cleanupStream struct {
 	streamID uint32
-	idPtr    *uint32
 	rst      bool
 	rstCode  http2.ErrCode
 	onWrite  func()
 }
 
+func (c *cleanupStream) isTransportResponseFrame() bool { return c.rst } // Results in a RST_STREAM
+
 type dataFrame struct {
 	streamID  uint32
 	endStream bool
@@ -120,30 +138,41 @@ type dataFrame struct {
 	onEachWrite func()
 }
 
+func (*dataFrame) isTransportResponseFrame() bool { return false }
+
 type incomingWindowUpdate struct {
 	streamID  uint32
 	increment uint32
 }
 
+func (*incomingWindowUpdate) isTransportResponseFrame() bool { return false }
+
 type outgoingWindowUpdate struct {
 	streamID  uint32
 	increment uint32
 }
 
+func (*outgoingWindowUpdate) isTransportResponseFrame() bool {
+	return false // window updates are throttled by thresholds
+}
+
 type incomingSettings struct {
 	ss []http2.Setting
 }
 
+func (*incomingSettings) isTransportResponseFrame() bool { return true } // Results in a settings ACK
+
 type outgoingSettings struct {
 	ss []http2.Setting
 }
 
-type settingsAck struct {
-}
+func (*outgoingSettings) isTransportResponseFrame() bool { return false }
 
 type incomingGoAway struct {
 }
 
+func (*incomingGoAway) isTransportResponseFrame() bool { return false }
+
 type goAway struct {
 	code      http2.ErrCode
 	debugData []byte
@@ -151,15 +180,21 @@ type goAway struct {
 	closeConn bool
 }
 
+func (*goAway) isTransportResponseFrame() bool { return false }
+
 type ping struct {
 	ack  bool
 	data [8]byte
 }
 
+func (*ping) isTransportResponseFrame() bool { return true }
+
 type outFlowControlSizeRequest struct {
 	resp chan uint32
 }
 
+func (*outFlowControlSizeRequest) isTransportResponseFrame() bool { return false }
+
 type outStreamState int
 
 const (
@@ -242,6 +277,14 @@ type controlBuffer struct {
 	consumerWaiting bool
 	list            *itemList
 	err             error
+
+	// transportResponseFrames counts the number of queued items that represent
+	// the response of an action initiated by the peer.  trfChan is created
+	// when transportResponseFrames >= maxQueuedTransportResponseFrames and is
+	// closed and nilled when transportResponseFrames drops below the
+	// threshold.  Both fields are protected by mu.
+	transportResponseFrames int
+	trfChan                 atomic.Value // *chan struct{}
 }
 
 func newControlBuffer(done <-chan struct{}) *controlBuffer {
@@ -252,12 +295,24 @@ func newControlBuffer(done <-chan struct{}) *controlBuffer {
 	}
 }
 
-func (c *controlBuffer) put(it interface{}) error {
+// throttle blocks if there are too many incomingSettings/cleanupStreams in the
+// controlbuf.
+func (c *controlBuffer) throttle() {
+	ch, _ := c.trfChan.Load().(*chan struct{})
+	if ch != nil {
+		select {
+		case <-*ch:
+		case <-c.done:
+		}
+	}
+}
+
+func (c *controlBuffer) put(it cbItem) error {
 	_, err := c.executeAndPut(nil, it)
 	return err
 }
 
-func (c *controlBuffer) executeAndPut(f func(it interface{}) bool, it interface{}) (bool, error) {
+func (c *controlBuffer) executeAndPut(f func(it interface{}) bool, it cbItem) (bool, error) {
 	var wakeUp bool
 	c.mu.Lock()
 	if c.err != nil {
@@ -275,6 +330,15 @@ func (c *controlBuffer) executeAndPut(f func(it interface{}) bool, it interface{
 		c.consumerWaiting = false
 	}
 	c.list.enqueue(it)
+	if it.isTransportResponseFrame() {
+		c.transportResponseFrames++
+		if c.transportResponseFrames == maxQueuedTransportResponseFrames {
+			// We are adding the frame that puts us over the threshold; create
+			// a throttling channel.
+			ch := make(chan struct{})
+			c.trfChan.Store(&ch)
+		}
+	}
 	c.mu.Unlock()
 	if wakeUp {
 		select {
@@ -308,7 +372,17 @@ func (c *controlBuffer) get(block bool) (interface{}, error) {
 			return nil, c.err
 		}
 		if !c.list.isEmpty() {
-			h := c.list.dequeue()
+			h := c.list.dequeue().(cbItem)
+			if h.isTransportResponseFrame() {
+				if c.transportResponseFrames == maxQueuedTransportResponseFrames {
+					// We are removing the frame that put us over the
+					// threshold; close and clear the throttling channel.
+					ch := c.trfChan.Load().(*chan struct{})
+					close(*ch)
+					c.trfChan.Store((*chan struct{})(nil))
+				}
+				c.transportResponseFrames--
+			}
 			c.mu.Unlock()
 			return h, nil
 		}
diff --git a/vendor/google.golang.org/grpc/internal/transport/flowcontrol.go b/vendor/google.golang.org/grpc/internal/transport/flowcontrol.go
index 5ea997a7..f262edd8 100644
--- a/vendor/google.golang.org/grpc/internal/transport/flowcontrol.go
+++ b/vendor/google.golang.org/grpc/internal/transport/flowcontrol.go
@@ -149,6 +149,7 @@ func (f *inFlow) maybeAdjust(n uint32) uint32 {
 		n = uint32(math.MaxInt32)
 	}
 	f.mu.Lock()
+	defer f.mu.Unlock()
 	// estSenderQuota is the receiver's view of the maximum number of bytes the sender
 	// can send without a window update.
 	estSenderQuota := int32(f.limit - (f.pendingData + f.pendingUpdate))
@@ -169,10 +170,8 @@ func (f *inFlow) maybeAdjust(n uint32) uint32 {
 			// is padded; We will fallback on the current available window(at least a 1/4th of the limit).
 			f.delta = n
 		}
-		f.mu.Unlock()
 		return f.delta
 	}
-	f.mu.Unlock()
 	return 0
 }
 
diff --git a/vendor/google.golang.org/grpc/internal/transport/go16.go b/vendor/google.golang.org/grpc/internal/transport/go16.go
deleted file mode 100644
index e0d00115..00000000
--- a/vendor/google.golang.org/grpc/internal/transport/go16.go
+++ /dev/null
@@ -1,52 +0,0 @@
-// +build go1.6,!go1.7
-
-/*
- *
- * Copyright 2016 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package transport
-
-import (
-	"net"
-	"net/http"
-
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/status"
-
-	"golang.org/x/net/context"
-)
-
-// dialContext connects to the address on the named network.
-func dialContext(ctx context.Context, network, address string) (net.Conn, error) {
-	return (&net.Dialer{Cancel: ctx.Done()}).Dial(network, address)
-}
-
-// ContextErr converts the error from context package into a status error.
-func ContextErr(err error) error {
-	switch err {
-	case context.DeadlineExceeded:
-		return status.Error(codes.DeadlineExceeded, err.Error())
-	case context.Canceled:
-		return status.Error(codes.Canceled, err.Error())
-	}
-	return status.Errorf(codes.Internal, "Unexpected error from context packet: %v", err)
-}
-
-// contextFromRequest returns a background context.
-func contextFromRequest(r *http.Request) context.Context {
-	return context.Background()
-}
diff --git a/vendor/google.golang.org/grpc/internal/transport/go17.go b/vendor/google.golang.org/grpc/internal/transport/go17.go
deleted file mode 100644
index 4d515b00..00000000
--- a/vendor/google.golang.org/grpc/internal/transport/go17.go
+++ /dev/null
@@ -1,53 +0,0 @@
-// +build go1.7
-
-/*
- *
- * Copyright 2016 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package transport
-
-import (
-	"context"
-	"net"
-	"net/http"
-
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/status"
-
-	netctx "golang.org/x/net/context"
-)
-
-// dialContext connects to the address on the named network.
-func dialContext(ctx context.Context, network, address string) (net.Conn, error) {
-	return (&net.Dialer{}).DialContext(ctx, network, address)
-}
-
-// ContextErr converts the error from context package into a status error.
-func ContextErr(err error) error {
-	switch err {
-	case context.DeadlineExceeded, netctx.DeadlineExceeded:
-		return status.Error(codes.DeadlineExceeded, err.Error())
-	case context.Canceled, netctx.Canceled:
-		return status.Error(codes.Canceled, err.Error())
-	}
-	return status.Errorf(codes.Internal, "Unexpected error from context packet: %v", err)
-}
-
-// contextFromRequest returns a context from the HTTP Request.
-func contextFromRequest(r *http.Request) context.Context {
-	return r.Context()
-}
diff --git a/vendor/google.golang.org/grpc/internal/transport/handler_server.go b/vendor/google.golang.org/grpc/internal/transport/handler_server.go
index bc856434..78f9ddc3 100644
--- a/vendor/google.golang.org/grpc/internal/transport/handler_server.go
+++ b/vendor/google.golang.org/grpc/internal/transport/handler_server.go
@@ -24,6 +24,8 @@
 package transport
 
 import (
+	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -34,7 +36,6 @@ import (
 	"time"
 
 	"github.com/golang/protobuf/proto"
-	"golang.org/x/net/context"
 	"golang.org/x/net/http2"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
@@ -63,9 +64,6 @@ func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats sta
 	if _, ok := w.(http.Flusher); !ok {
 		return nil, errors.New("gRPC requires a ResponseWriter supporting http.Flusher")
 	}
-	if _, ok := w.(http.CloseNotifier); !ok {
-		return nil, errors.New("gRPC requires a ResponseWriter supporting http.CloseNotifier")
-	}
 
 	st := &serverHandlerTransport{
 		rw:             w,
@@ -176,17 +174,11 @@ func (a strAddr) String() string { return string(a) }
 
 // do runs fn in the ServeHTTP goroutine.
 func (ht *serverHandlerTransport) do(fn func()) error {
-	// Avoid a panic writing to closed channel. Imperfect but maybe good enough.
 	select {
 	case <-ht.closedCh:
 		return ErrConnClosing
-	default:
-		select {
-		case ht.writes <- fn:
-			return nil
-		case <-ht.closedCh:
-			return ErrConnClosing
-		}
+	case ht.writes <- fn:
+		return nil
 	}
 }
 
@@ -237,9 +229,8 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) erro
 		if ht.stats != nil {
 			ht.stats.HandleRPC(s.Context(), &stats.OutTrailer{})
 		}
-		ht.Close()
-		close(ht.writes)
 	}
+	ht.Close()
 	return err
 }
 
@@ -307,7 +298,7 @@ func (ht *serverHandlerTransport) WriteHeader(s *Stream, md metadata.MD) error {
 func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), traceCtx func(context.Context, string) context.Context) {
 	// With this transport type there will be exactly 1 stream: this HTTP request.
 
-	ctx := contextFromRequest(ht.req)
+	ctx := ht.req.Context()
 	var cancel context.CancelFunc
 	if ht.timeoutSet {
 		ctx, cancel = context.WithTimeout(ctx, ht.timeout)
@@ -315,22 +306,16 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 		ctx, cancel = context.WithCancel(ctx)
 	}
 
-	// requestOver is closed when either the request's context is done
-	// or the status has been written via WriteStatus.
+	// requestOver is closed when the status has been written via WriteStatus.
 	requestOver := make(chan struct{})
-
-	// clientGone receives a single value if peer is gone, either
-	// because the underlying connection is dead or because the
-	// peer sends an http2 RST_STREAM.
-	clientGone := ht.rw.(http.CloseNotifier).CloseNotify()
 	go func() {
 		select {
 		case <-requestOver:
-			return
 		case <-ht.closedCh:
-		case <-clientGone:
+		case <-ht.req.Context().Done():
 		}
 		cancel()
+		ht.Close()
 	}()
 
 	req := ht.req
@@ -363,7 +348,7 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 		ht.stats.HandleRPC(s.ctx, inHeader)
 	}
 	s.trReader = &transportReader{
-		reader:        &recvBufferReader{ctx: s.ctx, ctxDone: s.ctx.Done(), recv: s.buf},
+		reader:        &recvBufferReader{ctx: s.ctx, ctxDone: s.ctx.Done(), recv: s.buf, freeBuffer: func(*bytes.Buffer) {}},
 		windowHandler: func(int) {},
 	}
 
@@ -377,7 +362,7 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 		for buf := make([]byte, readSize); ; {
 			n, err := req.Body.Read(buf)
 			if n > 0 {
-				s.buf.put(recvMsg{data: buf[:n:n]})
+				s.buf.put(recvMsg{buffer: bytes.NewBuffer(buf[:n:n])})
 				buf = buf[n:]
 			}
 			if err != nil {
@@ -407,10 +392,7 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 func (ht *serverHandlerTransport) runStream() {
 	for {
 		select {
-		case fn, ok := <-ht.writes:
-			if !ok {
-				return
-			}
+		case fn := <-ht.writes:
 			fn()
 		case <-ht.closedCh:
 			return
@@ -442,5 +424,8 @@ func mapRecvMsgError(err error) error {
 			return status.Error(code, se.Error())
 		}
 	}
+	if strings.Contains(err.Error(), "body closed by handler") {
+		return status.Error(codes.Canceled, err.Error())
+	}
 	return connectionErrorf(true, err, err.Error())
 }
diff --git a/vendor/google.golang.org/grpc/internal/transport/http2_client.go b/vendor/google.golang.org/grpc/internal/transport/http2_client.go
index 88d1c161..41a79c56 100644
--- a/vendor/google.golang.org/grpc/internal/transport/http2_client.go
+++ b/vendor/google.golang.org/grpc/internal/transport/http2_client.go
@@ -19,6 +19,8 @@
 package transport
 
 import (
+	"context"
+	"fmt"
 	"io"
 	"math"
 	"net"
@@ -28,13 +30,13 @@ import (
 	"sync/atomic"
 	"time"
 
-	"golang.org/x/net/context"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
 
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/internal/syscall"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
@@ -73,7 +75,7 @@ type http2Client struct {
 
 	isSecure bool
 
-	creds []credentials.PerRPCCredentials
+	perRPCCreds []credentials.PerRPCCredentials
 
 	// Boolean to keep track of reading activity on transport.
 	// 1 is true and 0 is false.
@@ -89,10 +91,10 @@ type http2Client struct {
 	maxSendHeaderListSize *uint32
 
 	bdpEst *bdpEstimator
-	// onSuccess is a callback that client transport calls upon
+	// onPrefaceReceipt is a callback that client transport calls upon
 	// receiving server preface to signal that a succefull HTTP2
 	// connection was established.
-	onSuccess func()
+	onPrefaceReceipt func()
 
 	maxConcurrentStreams  uint32
 	streamQuota           int64
@@ -111,26 +113,19 @@ type http2Client struct {
 
 	// Fields below are for channelz metric collection.
 	channelzID int64 // channelz unique identification number
-	czmu       sync.RWMutex
-	kpCount    int64
-	// The number of streams that have started, including already finished ones.
-	streamsStarted int64
-	// The number of streams that have ended successfully by receiving EoS bit set
-	// frame from server.
-	streamsSucceeded  int64
-	streamsFailed     int64
-	lastStreamCreated time.Time
-	msgSent           int64
-	msgRecv           int64
-	lastMsgSent       time.Time
-	lastMsgRecv       time.Time
+	czData     *channelzData
+
+	onGoAway func(GoAwayReason)
+	onClose  func()
+
+	bufferPool *bufferPool
 }
 
 func dial(ctx context.Context, fn func(context.Context, string) (net.Conn, error), addr string) (net.Conn, error) {
 	if fn != nil {
 		return fn(ctx, addr)
 	}
-	return dialContext(ctx, "tcp", addr)
+	return (&net.Dialer{}).DialContext(ctx, "tcp", addr)
 }
 
 func isTemporary(err error) bool {
@@ -152,7 +147,7 @@ func isTemporary(err error) bool {
 // newHTTP2Client constructs a connected ClientTransport to addr based on HTTP2
 // and starts to receive messages on it. Non-nil error returns if construction
 // fails.
-func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts ConnectOptions, onSuccess func()) (_ *http2Client, err error) {
+func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts ConnectOptions, onPrefaceReceipt func(), onGoAway func(GoAwayReason), onClose func()) (_ *http2Client, err error) {
 	scheme := "http"
 	ctx, cancel := context.WithCancel(ctx)
 	defer func() {
@@ -174,26 +169,44 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 			conn.Close()
 		}
 	}(conn)
+	kp := opts.KeepaliveParams
+	// Validate keepalive parameters.
+	if kp.Time == 0 {
+		kp.Time = defaultClientKeepaliveTime
+	}
+	if kp.Timeout == 0 {
+		kp.Timeout = defaultClientKeepaliveTimeout
+	}
+	keepaliveEnabled := false
+	if kp.Time != infinity {
+		if err = syscall.SetTCPUserTimeout(conn, kp.Timeout); err != nil {
+			return nil, connectionErrorf(false, err, "transport: failed to set TCP_USER_TIMEOUT: %v", err)
+		}
+		keepaliveEnabled = true
+	}
 	var (
 		isSecure bool
 		authInfo credentials.AuthInfo
 	)
-	if creds := opts.TransportCredentials; creds != nil {
+	transportCreds := opts.TransportCredentials
+	perRPCCreds := opts.PerRPCCredentials
+
+	if b := opts.CredsBundle; b != nil {
+		if t := b.TransportCredentials(); t != nil {
+			transportCreds = t
+		}
+		if t := b.PerRPCCredentials(); t != nil {
+			perRPCCreds = append(perRPCCreds, t)
+		}
+	}
+	if transportCreds != nil {
 		scheme = "https"
-		conn, authInfo, err = creds.ClientHandshake(connectCtx, addr.Authority, conn)
+		conn, authInfo, err = transportCreds.ClientHandshake(connectCtx, addr.Authority, conn)
 		if err != nil {
 			return nil, connectionErrorf(isTemporary(err), err, "transport: authentication handshake failed: %v", err)
 		}
 		isSecure = true
 	}
-	kp := opts.KeepaliveParams
-	// Validate keepalive parameters.
-	if kp.Time == 0 {
-		kp.Time = defaultClientKeepaliveTime
-	}
-	if kp.Timeout == 0 {
-		kp.Timeout = defaultClientKeepaliveTimeout
-	}
 	dynamicWindow := true
 	icwz := int32(initialWindowSize)
 	if opts.InitialConnWindowSize >= defaultWindowSize {
@@ -225,15 +238,20 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 		scheme:                scheme,
 		activeStreams:         make(map[uint32]*Stream),
 		isSecure:              isSecure,
-		creds:                 opts.PerRPCCredentials,
+		perRPCCreds:           perRPCCreds,
 		kp:                    kp,
 		statsHandler:          opts.StatsHandler,
 		initialWindowSize:     initialWindowSize,
-		onSuccess:             onSuccess,
+		onPrefaceReceipt:      onPrefaceReceipt,
 		nextID:                1,
 		maxConcurrentStreams:  defaultMaxStreamsClient,
 		streamQuota:           defaultMaxStreamsClient,
 		streamsQuotaAvailable: make(chan struct{}, 1),
+		czData:                new(channelzData),
+		onGoAway:              onGoAway,
+		onClose:               onClose,
+		keepaliveEnabled:      keepaliveEnabled,
+		bufferPool:            newBufferPool(),
 	}
 	t.controlBuf = newControlBuffer(t.ctxDone)
 	if opts.InitialWindowSize >= defaultWindowSize {
@@ -260,16 +278,16 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 		t.statsHandler.HandleConn(t.ctx, connBegin)
 	}
 	if channelz.IsOn() {
-		t.channelzID = channelz.RegisterNormalSocket(t, opts.ChannelzParentID, "")
+		t.channelzID = channelz.RegisterNormalSocket(t, opts.ChannelzParentID, fmt.Sprintf("%s -> %s", t.localAddr, t.remoteAddr))
 	}
-	if t.kp.Time != infinity {
-		t.keepaliveEnabled = true
+	if t.keepaliveEnabled {
 		go t.keepalive()
 	}
 	// Start the reader goroutine for incoming message. Each transport has
 	// a dedicated goroutine which reads HTTP2 frame from network. Then it
 	// dispatches the frame to the corresponding stream entity.
 	go t.reader()
+
 	// Send connection preface to server.
 	n, err := t.conn.Write(clientPreface)
 	if err != nil {
@@ -306,7 +324,10 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 			return nil, connectionErrorf(true, err, "transport: failed to write window update: %v", err)
 		}
 	}
-	t.framer.writer.Flush()
+
+	if err := t.framer.writer.Flush(); err != nil {
+		return nil, err
+	}
 	go func() {
 		t.loopy = newLoopyWriter(clientSide, t.framer, t.controlBuf, t.bdpEst)
 		err := t.loopy.run()
@@ -346,6 +367,10 @@ func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr) *Stream {
 			ctx:     s.ctx,
 			ctxDone: s.ctx.Done(),
 			recv:    s.buf,
+			closeStream: func(err error) {
+				t.CloseStream(s, err)
+			},
+			freeBuffer: t.bufferPool.put,
 		},
 		windowHandler: func(n int) {
 			t.updateWindow(s, uint32(n))
@@ -398,7 +423,7 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 	if dl, ok := ctx.Deadline(); ok {
 		// Send out timeout regardless its value. The server can detect timeout context by itself.
 		// TODO(mmukhi): Perhaps this field should be updated when actually writing out to the wire.
-		timeout := dl.Sub(time.Now())
+		timeout := time.Until(dl)
 		headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-timeout", Value: encodeTimeout(timeout)})
 	}
 	for k, v := range authData {
@@ -416,6 +441,15 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 
 	if md, added, ok := metadata.FromOutgoingContextRaw(ctx); ok {
 		var k string
+		for k, vv := range md {
+			// HTTP doesn't allow you to set pseudoheaders after non pseudoheaders were set.
+			if isReservedHeader(k) {
+				continue
+			}
+			for _, v := range vv {
+				headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
+			}
+		}
 		for _, vv := range added {
 			for i, v := range vv {
 				if i%2 == 0 {
@@ -429,15 +463,6 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 				headerFields = append(headerFields, hpack.HeaderField{Name: strings.ToLower(k), Value: encodeMetadataHeader(k, v)})
 			}
 		}
-		for k, vv := range md {
-			// HTTP doesn't allow you to set pseudoheaders after non pseudoheaders were set.
-			if isReservedHeader(k) {
-				continue
-			}
-			for _, v := range vv {
-				headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
-			}
-		}
 	}
 	if md, ok := t.md.(*metadata.MD); ok {
 		for k, vv := range *md {
@@ -454,7 +479,7 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 
 func (t *http2Client) createAudience(callHdr *CallHdr) string {
 	// Create an audience string only if needed.
-	if len(t.creds) == 0 && callHdr.Creds == nil {
+	if len(t.perRPCCreds) == 0 && callHdr.Creds == nil {
 		return ""
 	}
 	// Construct URI required to get auth request metadata.
@@ -468,8 +493,11 @@ func (t *http2Client) createAudience(callHdr *CallHdr) string {
 }
 
 func (t *http2Client) getTrAuthData(ctx context.Context, audience string) (map[string]string, error) {
+	if len(t.perRPCCreds) == 0 {
+		return nil, nil
+	}
 	authData := map[string]string{}
-	for _, c := range t.creds {
+	for _, c := range t.perRPCCreds {
 		data, err := c.GetRequestMetadata(ctx, audience)
 		if err != nil {
 			if _, ok := status.FromError(err); ok {
@@ -488,7 +516,7 @@ func (t *http2Client) getTrAuthData(ctx context.Context, audience string) (map[s
 }
 
 func (t *http2Client) getCallAuthData(ctx context.Context, audience string, callHdr *CallHdr) (map[string]string, error) {
-	callAuthData := map[string]string{}
+	var callAuthData map[string]string
 	// Check if credentials.PerRPCCredentials were provided via call options.
 	// Note: if these credentials are provided both via dial options and call
 	// options, then both sets of credentials will be applied.
@@ -500,6 +528,7 @@ func (t *http2Client) getCallAuthData(ctx context.Context, audience string, call
 		if err != nil {
 			return nil, status.Errorf(codes.Internal, "transport: %v", err)
 		}
+		callAuthData = make(map[string]string, len(data))
 		for k, v := range data {
 			// Capital header names are illegal in HTTP/2
 			k = strings.ToLower(k)
@@ -528,10 +557,9 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		s.write(recvMsg{err: err})
 		close(s.done)
 		// If headerChan isn't closed, then close it.
-		if atomic.SwapUint32(&s.headerDone, 1) == 0 {
+		if atomic.CompareAndSwapUint32(&s.headerChanClosed, 0, 1) {
 			close(s.headerChan)
 		}
-
 	}
 	hdr := &headerFrame{
 		hf:        headerFields,
@@ -550,10 +578,8 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 			}
 			t.activeStreams[id] = s
 			if channelz.IsOn() {
-				t.czmu.Lock()
-				t.streamsStarted++
-				t.lastStreamCreated = time.Now()
-				t.czmu.Unlock()
+				atomic.AddInt64(&t.czData.streamsStarted, 1)
+				atomic.StoreInt64(&t.czData.lastStreamCreatedTime, time.Now().UnixNano())
 			}
 			var sendPing bool
 			// If the number of active streams change from 0 to 1, then check if keepalive
@@ -677,7 +703,9 @@ func (t *http2Client) CloseStream(s *Stream, err error) {
 func (t *http2Client) closeStream(s *Stream, err error, rst bool, rstCode http2.ErrCode, st *status.Status, mdata map[string][]string, eosReceived bool) {
 	// Set stream status to done.
 	if s.swapState(streamDone) == streamDone {
-		// If it was already done, return.
+		// If it was already done, return.  If multiple closeStream calls
+		// happen simultaneously, wait for the first to finish.
+		<-s.done
 		return
 	}
 	// status and trailers can be updated here without any synchronization because the stream goroutine will
@@ -691,10 +719,8 @@ func (t *http2Client) closeStream(s *Stream, err error, rst bool, rstCode http2.
 		// This will unblock reads eventually.
 		s.write(recvMsg{err: err})
 	}
-	// This will unblock write.
-	close(s.done)
 	// If headerChan isn't closed, then close it.
-	if atomic.SwapUint32(&s.headerDone, 1) == 0 {
+	if atomic.CompareAndSwapUint32(&s.headerChanClosed, 0, 1) {
 		s.noHeaders = true
 		close(s.headerChan)
 	}
@@ -707,13 +733,11 @@ func (t *http2Client) closeStream(s *Stream, err error, rst bool, rstCode http2.
 			}
 			t.mu.Unlock()
 			if channelz.IsOn() {
-				t.czmu.Lock()
 				if eosReceived {
-					t.streamsSucceeded++
+					atomic.AddInt64(&t.czData.streamsSucceeded, 1)
 				} else {
-					t.streamsFailed++
+					atomic.AddInt64(&t.czData.streamsFailed, 1)
 				}
-				t.czmu.Unlock()
 			}
 		},
 		rst:     rst,
@@ -730,11 +754,17 @@ func (t *http2Client) closeStream(s *Stream, err error, rst bool, rstCode http2.
 		return true
 	}
 	t.controlBuf.executeAndPut(addBackStreamQuota, cleanup)
+	// This will unblock write.
+	close(s.done)
 }
 
 // Close kicks off the shutdown process of the transport. This should be called
 // only once on a transport. Once it is called, the transport should not be
 // accessed any more.
+//
+// This method blocks until the addrConn that initiated this transport is
+// re-connected. This happens because t.onClose() begins reconnect logic at the
+// addrConn level and blocks until the addrConn is successfully connected.
 func (t *http2Client) Close() error {
 	t.mu.Lock()
 	// Make sure we only Close once.
@@ -742,6 +772,9 @@ func (t *http2Client) Close() error {
 		t.mu.Unlock()
 		return nil
 	}
+	// Call t.onClose before setting the state to closing to prevent the client
+	// from attempting to create new streams ASAP.
+	t.onClose()
 	t.state = closing
 	streams := t.activeStreams
 	t.activeStreams = nil
@@ -770,21 +803,21 @@ func (t *http2Client) Close() error {
 // stream is closed.  If there are no active streams, the transport is closed
 // immediately.  This does nothing if the transport is already draining or
 // closing.
-func (t *http2Client) GracefulClose() error {
+func (t *http2Client) GracefulClose() {
 	t.mu.Lock()
 	// Make sure we move to draining only from active.
 	if t.state == draining || t.state == closing {
 		t.mu.Unlock()
-		return nil
+		return
 	}
 	t.state = draining
 	active := len(t.activeStreams)
 	t.mu.Unlock()
 	if active == 0 {
-		return t.Close()
+		t.Close()
+		return
 	}
 	t.controlBuf.put(&incomingGoAway{})
-	return nil
 }
 
 // Write formats the data into HTTP2 data frame(s) and sends it out. The caller
@@ -922,9 +955,10 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 		// guarantee f.Data() is consumed before the arrival of next frame.
 		// Can this copy be eliminated?
 		if len(f.Data()) > 0 {
-			data := make([]byte, len(f.Data()))
-			copy(data, f.Data())
-			s.write(recvMsg{data: data})
+			buffer := t.bufferPool.get()
+			buffer.Reset()
+			buffer.Write(f.Data())
+			s.write(recvMsg{buffer: buffer})
 		}
 	}
 	// The server has closed the stream without sending trailers.  Record that
@@ -949,9 +983,9 @@ func (t *http2Client) handleRSTStream(f *http2.RSTStreamFrame) {
 		statusCode = codes.Unknown
 	}
 	if statusCode == codes.Canceled {
-		// Our deadline was already exceeded, and that was likely the cause of
-		// this cancelation.  Alter the status code accordingly.
-		if d, ok := s.ctx.Deadline(); ok && d.After(time.Now()) {
+		if d, ok := s.ctx.Deadline(); ok && !d.After(time.Now()) {
+			// Our deadline was already exceeded, and that was likely the cause
+			// of this cancelation.  Alter the status code accordingly.
 			statusCode = codes.DeadlineExceeded
 		}
 	}
@@ -1056,8 +1090,12 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 	default:
 		t.setGoAwayReason(f)
 		close(t.goAway)
-		t.state = draining
 		t.controlBuf.put(&incomingGoAway{})
+		// Notify the clientconn about the GOAWAY before we set the state to
+		// draining, to allow the client to stop attempting to create streams
+		// before disallowing new streams on this connection.
+		t.onGoAway(t.goAwayReason)
+		t.state = draining
 	}
 	// All streams with IDs greater than the GoAwayId
 	// and smaller than the previous GoAway ID should be killed.
@@ -1113,16 +1151,26 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 	if !ok {
 		return
 	}
+	endStream := frame.StreamEnded()
 	atomic.StoreUint32(&s.bytesReceived, 1)
-	var state decodeState
+	initialHeader := atomic.LoadUint32(&s.headerChanClosed) == 0
+
+	if !initialHeader && !endStream {
+		// As specified by gRPC over HTTP2, a HEADERS frame (and associated CONTINUATION frames) can only appear at the start or end of a stream. Therefore, second HEADERS frame must have EOS bit set.
+		st := status.New(codes.Internal, "a HEADERS frame cannot appear in the middle of a stream")
+		t.closeStream(s, st.Err(), true, http2.ErrCodeProtocol, st, nil, false)
+		return
+	}
+
+	state := &decodeState{}
+	// Initialize isGRPC value to be !initialHeader, since if a gRPC Response-Headers has already been received, then it means that the peer is speaking gRPC and we are in gRPC mode.
+	state.data.isGRPC = !initialHeader
 	if err := state.decodeHeader(frame); err != nil {
-		t.closeStream(s, err, true, http2.ErrCodeProtocol, status.New(codes.Internal, err.Error()), nil, false)
-		// Something wrong. Stops reading even when there is remaining.
+		t.closeStream(s, err, true, http2.ErrCodeProtocol, status.Convert(err), nil, endStream)
 		return
 	}
 
-	endStream := frame.StreamEnded()
-	var isHeader bool
+	isHeader := false
 	defer func() {
 		if t.statsHandler != nil {
 			if isHeader {
@@ -1140,27 +1188,33 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 			}
 		}
 	}()
-	// If headers haven't been received yet.
-	if atomic.SwapUint32(&s.headerDone, 1) == 0 {
+
+	// If headerChan hasn't been closed yet
+	if atomic.CompareAndSwapUint32(&s.headerChanClosed, 0, 1) {
 		if !endStream {
-			// Headers frame is not actually a trailers-only frame.
+			// HEADERS frame block carries a Response-Headers.
 			isHeader = true
 			// These values can be set without any synchronization because
 			// stream goroutine will read it only after seeing a closed
 			// headerChan which we'll close after setting this.
-			s.recvCompress = state.encoding
-			if len(state.mdata) > 0 {
-				s.header = state.mdata
+			s.recvCompress = state.data.encoding
+			if len(state.data.mdata) > 0 {
+				s.header = state.data.mdata
 			}
 		} else {
+			// HEADERS frame block carries a Trailers-Only.
 			s.noHeaders = true
 		}
 		close(s.headerChan)
 	}
+
 	if !endStream {
 		return
 	}
-	t.closeStream(s, io.EOF, false, http2.ErrCodeNo, state.status(), state.mdata, true)
+
+	// if client received END_STREAM from server while stream was still active, send RST_STREAM
+	rst := s.getState() == streamActive
+	t.closeStream(s, io.EOF, rst, http2.ErrCodeNo, state.status(), state.data.mdata, true)
 }
 
 // reader runs as a separate goroutine in charge of reading data from network
@@ -1174,22 +1228,24 @@ func (t *http2Client) reader() {
 	// Check the validity of server preface.
 	frame, err := t.framer.fr.ReadFrame()
 	if err != nil {
-		t.Close()
+		t.Close() // this kicks off resetTransport, so must be last before return
 		return
 	}
+	t.conn.SetReadDeadline(time.Time{}) // reset deadline once we get the settings frame (we didn't time out, yay!)
 	if t.keepaliveEnabled {
 		atomic.CompareAndSwapUint32(&t.activity, 0, 1)
 	}
 	sf, ok := frame.(*http2.SettingsFrame)
 	if !ok {
-		t.Close()
+		t.Close() // this kicks off resetTransport, so must be last before return
 		return
 	}
-	t.onSuccess()
+	t.onPrefaceReceipt()
 	t.handleSettings(sf, true)
 
 	// loop to keep reading incoming messages on this transport.
 	for {
+		t.controlBuf.throttle()
 		frame, err := t.framer.fr.ReadFrame()
 		if t.keepaliveEnabled {
 			atomic.CompareAndSwapUint32(&t.activity, 0, 1)
@@ -1263,9 +1319,7 @@ func (t *http2Client) keepalive() {
 			} else {
 				t.mu.Unlock()
 				if channelz.IsOn() {
-					t.czmu.Lock()
-					t.kpCount++
-					t.czmu.Unlock()
+					atomic.AddInt64(&t.czData.kpCount, 1)
 				}
 				// Send ping.
 				t.controlBuf.put(p)
@@ -1279,6 +1333,7 @@ func (t *http2Client) keepalive() {
 					timer.Reset(t.kp.Time)
 					continue
 				}
+				infof("transport: closing client transport due to idleness.")
 				t.Close()
 				return
 			case <-t.ctx.Done():
@@ -1305,17 +1360,16 @@ func (t *http2Client) GoAway() <-chan struct{} {
 }
 
 func (t *http2Client) ChannelzMetric() *channelz.SocketInternalMetric {
-	t.czmu.RLock()
 	s := channelz.SocketInternalMetric{
-		StreamsStarted:                  t.streamsStarted,
-		StreamsSucceeded:                t.streamsSucceeded,
-		StreamsFailed:                   t.streamsFailed,
-		MessagesSent:                    t.msgSent,
-		MessagesReceived:                t.msgRecv,
-		KeepAlivesSent:                  t.kpCount,
-		LastLocalStreamCreatedTimestamp: t.lastStreamCreated,
-		LastMessageSentTimestamp:        t.lastMsgSent,
-		LastMessageReceivedTimestamp:    t.lastMsgRecv,
+		StreamsStarted:                  atomic.LoadInt64(&t.czData.streamsStarted),
+		StreamsSucceeded:                atomic.LoadInt64(&t.czData.streamsSucceeded),
+		StreamsFailed:                   atomic.LoadInt64(&t.czData.streamsFailed),
+		MessagesSent:                    atomic.LoadInt64(&t.czData.msgSent),
+		MessagesReceived:                atomic.LoadInt64(&t.czData.msgRecv),
+		KeepAlivesSent:                  atomic.LoadInt64(&t.czData.kpCount),
+		LastLocalStreamCreatedTimestamp: time.Unix(0, atomic.LoadInt64(&t.czData.lastStreamCreatedTime)),
+		LastMessageSentTimestamp:        time.Unix(0, atomic.LoadInt64(&t.czData.lastMsgSentTime)),
+		LastMessageReceivedTimestamp:    time.Unix(0, atomic.LoadInt64(&t.czData.lastMsgRecvTime)),
 		LocalFlowControlWindow:          int64(t.fc.getSize()),
 		SocketOptions:                   channelz.GetSocketOption(t.conn),
 		LocalAddr:                       t.localAddr,
@@ -1325,23 +1379,20 @@ func (t *http2Client) ChannelzMetric() *channelz.SocketInternalMetric {
 	if au, ok := t.authInfo.(credentials.ChannelzSecurityInfo); ok {
 		s.Security = au.GetSecurityValue()
 	}
-	t.czmu.RUnlock()
 	s.RemoteFlowControlWindow = t.getOutFlowWindow()
 	return &s
 }
 
+func (t *http2Client) RemoteAddr() net.Addr { return t.remoteAddr }
+
 func (t *http2Client) IncrMsgSent() {
-	t.czmu.Lock()
-	t.msgSent++
-	t.lastMsgSent = time.Now()
-	t.czmu.Unlock()
+	atomic.AddInt64(&t.czData.msgSent, 1)
+	atomic.StoreInt64(&t.czData.lastMsgSentTime, time.Now().UnixNano())
 }
 
 func (t *http2Client) IncrMsgRecv() {
-	t.czmu.Lock()
-	t.msgRecv++
-	t.lastMsgRecv = time.Now()
-	t.czmu.Unlock()
+	atomic.AddInt64(&t.czData.msgRecv, 1)
+	atomic.StoreInt64(&t.czData.lastMsgRecvTime, time.Now().UnixNano())
 }
 
 func (t *http2Client) getOutFlowWindow() int64 {
diff --git a/vendor/google.golang.org/grpc/internal/transport/http2_server.go b/vendor/google.golang.org/grpc/internal/transport/http2_server.go
index a8a09270..83439b56 100644
--- a/vendor/google.golang.org/grpc/internal/transport/http2_server.go
+++ b/vendor/google.golang.org/grpc/internal/transport/http2_server.go
@@ -20,6 +20,7 @@ package transport
 
 import (
 	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -31,13 +32,14 @@ import (
 	"time"
 
 	"github.com/golang/protobuf/proto"
-	"golang.org/x/net/context"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
 
+	spb "google.golang.org/genproto/googleapis/rpc/status"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal"
 	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/internal/grpcrand"
 	"google.golang.org/grpc/keepalive"
@@ -55,6 +57,9 @@ var (
 	// ErrHeaderListSizeLimitViolation indicates that the header list size is larger
 	// than the limit set by peer.
 	ErrHeaderListSizeLimitViolation = errors.New("transport: trying to send header list size larger than the limit set by peer")
+	// statusRawProto is a function to get to the raw status proto wrapped in a
+	// status.Status without a proto.Clone().
+	statusRawProto = internal.StatusRawProto.(func(*status.Status) *spb.Status)
 )
 
 // http2Server implements the ServerTransport interface with HTTP2.
@@ -118,19 +123,8 @@ type http2Server struct {
 
 	// Fields below are for channelz metric collection.
 	channelzID int64 // channelz unique identification number
-	czmu       sync.RWMutex
-	kpCount    int64
-	// The number of streams that have started, including already finished ones.
-	streamsStarted int64
-	// The number of streams that have ended successfully by sending frame with
-	// EoS bit set.
-	streamsSucceeded  int64
-	streamsFailed     int64
-	lastStreamCreated time.Time
-	msgSent           int64
-	msgRecv           int64
-	lastMsgSent       time.Time
-	lastMsgRecv       time.Time
+	czData     *channelzData
+	bufferPool *bufferPool
 }
 
 // newHTTP2Server constructs a ServerTransport based on HTTP2. ConnectionError is
@@ -231,6 +225,8 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 		idle:              time.Now(),
 		kep:               kep,
 		initialWindowSize: iwz,
+		czData:            new(channelzData),
+		bufferPool:        newBufferPool(),
 	}
 	t.controlBuf = newControlBuffer(t.ctxDone)
 	if dynamicWindow {
@@ -248,7 +244,7 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 		t.stats.HandleConn(t.ctx, connBegin)
 	}
 	if channelz.IsOn() {
-		t.channelzID = channelz.RegisterNormalSocket(t, config.ChannelzParentID, "")
+		t.channelzID = channelz.RegisterNormalSocket(t, config.ChannelzParentID, fmt.Sprintf("%s -> %s", t.remoteAddr, t.localAddr))
 	}
 	t.framer.writer.Flush()
 
@@ -295,9 +291,11 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 }
 
 // operateHeader takes action on the decoded headers.
-func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (close bool) {
+func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (fatal bool) {
 	streamID := frame.Header().StreamID
-	state := decodeState{serverSide: true}
+	state := &decodeState{
+		serverSide: true,
+	}
 	if err := state.decodeHeader(frame); err != nil {
 		if se, ok := status.FromError(err); ok {
 			t.controlBuf.put(&cleanupStream{
@@ -307,7 +305,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 				onWrite:  func() {},
 			})
 		}
-		return
+		return false
 	}
 
 	buf := newRecvBuffer()
@@ -316,16 +314,16 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 		st:             t,
 		buf:            buf,
 		fc:             &inFlow{limit: uint32(t.initialWindowSize)},
-		recvCompress:   state.encoding,
-		method:         state.method,
-		contentSubtype: state.contentSubtype,
+		recvCompress:   state.data.encoding,
+		method:         state.data.method,
+		contentSubtype: state.data.contentSubtype,
 	}
 	if frame.StreamEnded() {
 		// s is just created by the caller. No lock needed.
 		s.state = streamReadDone
 	}
-	if state.timeoutSet {
-		s.ctx, s.cancel = context.WithTimeout(t.ctx, state.timeout)
+	if state.data.timeoutSet {
+		s.ctx, s.cancel = context.WithTimeout(t.ctx, state.data.timeout)
 	} else {
 		s.ctx, s.cancel = context.WithCancel(t.ctx)
 	}
@@ -338,19 +336,19 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	}
 	s.ctx = peer.NewContext(s.ctx, pr)
 	// Attach the received metadata to the context.
-	if len(state.mdata) > 0 {
-		s.ctx = metadata.NewIncomingContext(s.ctx, state.mdata)
+	if len(state.data.mdata) > 0 {
+		s.ctx = metadata.NewIncomingContext(s.ctx, state.data.mdata)
 	}
-	if state.statsTags != nil {
-		s.ctx = stats.SetIncomingTags(s.ctx, state.statsTags)
+	if state.data.statsTags != nil {
+		s.ctx = stats.SetIncomingTags(s.ctx, state.data.statsTags)
 	}
-	if state.statsTrace != nil {
-		s.ctx = stats.SetIncomingTrace(s.ctx, state.statsTrace)
+	if state.data.statsTrace != nil {
+		s.ctx = stats.SetIncomingTrace(s.ctx, state.data.statsTrace)
 	}
 	if t.inTapHandle != nil {
 		var err error
 		info := &tap.Info{
-			FullMethodName: state.method,
+			FullMethodName: state.data.method,
 		}
 		s.ctx, err = t.inTapHandle(s.ctx, info)
 		if err != nil {
@@ -361,13 +359,13 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 				rstCode:  http2.ErrCodeRefusedStream,
 				onWrite:  func() {},
 			})
-			return
+			return false
 		}
 	}
 	t.mu.Lock()
 	if t.state != reachable {
 		t.mu.Unlock()
-		return
+		return false
 	}
 	if uint32(len(t.activeStreams)) >= t.maxStreams {
 		t.mu.Unlock()
@@ -377,7 +375,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 			rstCode:  http2.ErrCodeRefusedStream,
 			onWrite:  func() {},
 		})
-		return
+		return false
 	}
 	if streamID%2 != 1 || streamID <= t.maxStreamID {
 		t.mu.Unlock()
@@ -392,10 +390,8 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	}
 	t.mu.Unlock()
 	if channelz.IsOn() {
-		t.czmu.Lock()
-		t.streamsStarted++
-		t.lastStreamCreated = time.Now()
-		t.czmu.Unlock()
+		atomic.AddInt64(&t.czData.streamsStarted, 1)
+		atomic.StoreInt64(&t.czData.lastStreamCreatedTime, time.Now().UnixNano())
 	}
 	s.requestRead = func(n int) {
 		t.adjustWindow(s, uint32(n))
@@ -416,9 +412,10 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	s.wq = newWriteQuota(defaultWriteQuota, s.ctxDone)
 	s.trReader = &transportReader{
 		reader: &recvBufferReader{
-			ctx:     s.ctx,
-			ctxDone: s.ctxDone,
-			recv:    s.buf,
+			ctx:        s.ctx,
+			ctxDone:    s.ctxDone,
+			recv:       s.buf,
+			freeBuffer: t.bufferPool.put,
 		},
 		windowHandler: func(n int) {
 			t.updateWindow(s, uint32(n))
@@ -430,7 +427,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 		wq:       s.wq,
 	})
 	handle(s)
-	return
+	return false
 }
 
 // HandleStreams receives incoming streams using the given handler. This is
@@ -439,6 +436,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.Context, string) context.Context) {
 	defer close(t.readerDone)
 	for {
+		t.controlBuf.throttle()
 		frame, err := t.framer.fr.ReadFrame()
 		atomic.StoreUint32(&t.activity, 1)
 		if err != nil {
@@ -448,7 +446,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 				s := t.activeStreams[se.StreamID]
 				t.mu.Unlock()
 				if s != nil {
-					t.closeStream(s, true, se.Code, nil, false)
+					t.closeStream(s, true, se.Code, false)
 				} else {
 					t.controlBuf.put(&cleanupStream{
 						streamID: se.StreamID,
@@ -590,7 +588,7 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 	}
 	if size > 0 {
 		if err := s.fc.onData(size); err != nil {
-			t.closeStream(s, true, http2.ErrCodeFlowControl, nil, false)
+			t.closeStream(s, true, http2.ErrCodeFlowControl, false)
 			return
 		}
 		if f.Header().Flags.Has(http2.FlagDataPadded) {
@@ -602,9 +600,10 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 		// guarantee f.Data() is consumed before the arrival of next frame.
 		// Can this copy be eliminated?
 		if len(f.Data()) > 0 {
-			data := make([]byte, len(f.Data()))
-			copy(data, f.Data())
-			s.write(recvMsg{data: data})
+			buffer := t.bufferPool.get()
+			buffer.Reset()
+			buffer.Write(f.Data())
+			s.write(recvMsg{buffer: buffer})
 		}
 	}
 	if f.Header().Flags.Has(http2.FlagDataEndStream) {
@@ -615,11 +614,18 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 }
 
 func (t *http2Server) handleRSTStream(f *http2.RSTStreamFrame) {
-	s, ok := t.getStream(f)
-	if !ok {
+	// If the stream is not deleted from the transport's active streams map, then do a regular close stream.
+	if s, ok := t.getStream(f); ok {
+		t.closeStream(s, false, 0, false)
 		return
 	}
-	t.closeStream(s, false, 0, nil, false)
+	// If the stream is already deleted from the active streams map, then put a cleanupStream item into controlbuf to delete the stream from loopy writer's established streams map.
+	t.controlBuf.put(&cleanupStream{
+		streamID: f.Header().StreamID,
+		rst:      false,
+		rstCode:  0,
+		onWrite:  func() {},
+	})
 }
 
 func (t *http2Server) handleSettings(f *http2.SettingsFrame) {
@@ -761,6 +767,10 @@ func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
 	return nil
 }
 
+func (t *http2Server) setResetPingStrikes() {
+	atomic.StoreUint32(&t.resetPingStrikes, 1)
+}
+
 func (t *http2Server) writeHeaderLocked(s *Stream) error {
 	// TODO(mmukhi): Benchmark if the performance gets better if count the metadata and other header fields
 	// first and create a slice of that exact size.
@@ -775,15 +785,13 @@ func (t *http2Server) writeHeaderLocked(s *Stream) error {
 		streamID:  s.id,
 		hf:        headerFields,
 		endStream: false,
-		onWrite: func() {
-			atomic.StoreUint32(&t.resetPingStrikes, 1)
-		},
+		onWrite:   t.setResetPingStrikes,
 	})
 	if !success {
 		if err != nil {
 			return err
 		}
-		t.closeStream(s, true, http2.ErrCodeInternal, nil, false)
+		t.closeStream(s, true, http2.ErrCodeInternal, false)
 		return ErrHeaderListSizeLimitViolation
 	}
 	if t.stats != nil {
@@ -821,7 +829,7 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 	headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-status", Value: strconv.Itoa(int(st.Code()))})
 	headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(st.Message())})
 
-	if p := st.Proto(); p != nil && len(p.Details) > 0 {
+	if p := statusRawProto(st); p != nil && len(p.Details) > 0 {
 		stBytes, err := proto.Marshal(p)
 		if err != nil {
 			// TODO: return error instead, when callers are able to handle it.
@@ -837,9 +845,7 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 		streamID:  s.id,
 		hf:        headerFields,
 		endStream: true,
-		onWrite: func() {
-			atomic.StoreUint32(&t.resetPingStrikes, 1)
-		},
+		onWrite:   t.setResetPingStrikes,
 	}
 	s.hdrMu.Unlock()
 	success, err := t.controlBuf.execute(t.checkForHeaderListSize, trailingHeader)
@@ -847,10 +853,12 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 		if err != nil {
 			return err
 		}
-		t.closeStream(s, true, http2.ErrCodeInternal, nil, false)
+		t.closeStream(s, true, http2.ErrCodeInternal, false)
 		return ErrHeaderListSizeLimitViolation
 	}
-	t.closeStream(s, false, 0, trailingHeader, true)
+	// Send a RST_STREAM after the trailers if the client has not already half-closed.
+	rst := s.getState() == streamActive
+	t.finishStream(s, rst, http2.ErrCodeNo, trailingHeader, true)
 	if t.stats != nil {
 		t.stats.HandleRPC(s.Context(), &stats.OutTrailer{})
 	}
@@ -862,6 +870,9 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 func (t *http2Server) Write(s *Stream, hdr []byte, data []byte, opts *Options) error {
 	if !s.isHeaderSent() { // Headers haven't been written yet.
 		if err := t.WriteHeader(s, nil); err != nil {
+			if _, ok := err.(ConnectionError); ok {
+				return err
+			}
 			// TODO(mmukhi, dfawley): Make sure this is the right code to return.
 			return status.Errorf(codes.Internal, "transport: %v", err)
 		}
@@ -886,12 +897,10 @@ func (t *http2Server) Write(s *Stream, hdr []byte, data []byte, opts *Options) e
 	hdr = append(hdr, data[:emptyLen]...)
 	data = data[emptyLen:]
 	df := &dataFrame{
-		streamID: s.id,
-		h:        hdr,
-		d:        data,
-		onEachWrite: func() {
-			atomic.StoreUint32(&t.resetPingStrikes, 1)
-		},
+		streamID:    s.id,
+		h:           hdr,
+		d:           data,
+		onEachWrite: t.setResetPingStrikes,
 	}
 	if err := s.wq.get(int32(len(hdr) + len(data))); err != nil {
 		select {
@@ -957,6 +966,7 @@ func (t *http2Server) keepalive() {
 			select {
 			case <-maxAge.C:
 				// Close the connection after grace period.
+				infof("transport: closing server transport due to maximum connection age.")
 				t.Close()
 				// Resetting the timer so that the clean-up doesn't deadlock.
 				maxAge.Reset(infinity)
@@ -970,6 +980,7 @@ func (t *http2Server) keepalive() {
 				continue
 			}
 			if pingSent {
+				infof("transport: closing server transport due to idleness.")
 				t.Close()
 				// Resetting the timer so that the clean-up doesn't deadlock.
 				keepalive.Reset(infinity)
@@ -977,9 +988,7 @@ func (t *http2Server) keepalive() {
 			}
 			pingSent = true
 			if channelz.IsOn() {
-				t.czmu.Lock()
-				t.kpCount++
-				t.czmu.Unlock()
+				atomic.AddInt64(&t.czData.kpCount, 1)
 			}
 			t.controlBuf.put(p)
 			keepalive.Reset(t.kp.Timeout)
@@ -1019,47 +1028,61 @@ func (t *http2Server) Close() error {
 	return err
 }
 
-// closeStream clears the footprint of a stream when the stream is not needed
-// any more.
-func (t *http2Server) closeStream(s *Stream, rst bool, rstCode http2.ErrCode, hdr *headerFrame, eosReceived bool) {
-	if s.swapState(streamDone) == streamDone {
-		// If the stream was already done, return.
-		return
-	}
+// deleteStream deletes the stream s from transport's active streams.
+func (t *http2Server) deleteStream(s *Stream, eosReceived bool) {
 	// In case stream sending and receiving are invoked in separate
 	// goroutines (e.g., bi-directional streaming), cancel needs to be
 	// called to interrupt the potential blocking on other goroutines.
 	s.cancel()
-	cleanup := &cleanupStream{
+
+	t.mu.Lock()
+	if _, ok := t.activeStreams[s.id]; ok {
+		delete(t.activeStreams, s.id)
+		if len(t.activeStreams) == 0 {
+			t.idle = time.Now()
+		}
+	}
+	t.mu.Unlock()
+
+	if channelz.IsOn() {
+		if eosReceived {
+			atomic.AddInt64(&t.czData.streamsSucceeded, 1)
+		} else {
+			atomic.AddInt64(&t.czData.streamsFailed, 1)
+		}
+	}
+}
+
+// finishStream closes the stream and puts the trailing headerFrame into controlbuf.
+func (t *http2Server) finishStream(s *Stream, rst bool, rstCode http2.ErrCode, hdr *headerFrame, eosReceived bool) {
+	oldState := s.swapState(streamDone)
+	if oldState == streamDone {
+		// If the stream was already done, return.
+		return
+	}
+
+	hdr.cleanup = &cleanupStream{
 		streamID: s.id,
 		rst:      rst,
 		rstCode:  rstCode,
 		onWrite: func() {
-			t.mu.Lock()
-			if t.activeStreams != nil {
-				delete(t.activeStreams, s.id)
-				if len(t.activeStreams) == 0 {
-					t.idle = time.Now()
-				}
-			}
-			t.mu.Unlock()
-			if channelz.IsOn() {
-				t.czmu.Lock()
-				if eosReceived {
-					t.streamsSucceeded++
-				} else {
-					t.streamsFailed++
-				}
-				t.czmu.Unlock()
-			}
+			t.deleteStream(s, eosReceived)
 		},
 	}
-	if hdr != nil {
-		hdr.cleanup = cleanup
-		t.controlBuf.put(hdr)
-	} else {
-		t.controlBuf.put(cleanup)
-	}
+	t.controlBuf.put(hdr)
+}
+
+// closeStream clears the footprint of a stream when the stream is not needed any more.
+func (t *http2Server) closeStream(s *Stream, rst bool, rstCode http2.ErrCode, eosReceived bool) {
+	s.swapState(streamDone)
+	t.deleteStream(s, eosReceived)
+
+	t.controlBuf.put(&cleanupStream{
+		streamID: s.id,
+		rst:      rst,
+		rstCode:  rstCode,
+		onWrite:  func() {},
+	})
 }
 
 func (t *http2Server) RemoteAddr() net.Addr {
@@ -1138,17 +1161,16 @@ func (t *http2Server) outgoingGoAwayHandler(g *goAway) (bool, error) {
 }
 
 func (t *http2Server) ChannelzMetric() *channelz.SocketInternalMetric {
-	t.czmu.RLock()
 	s := channelz.SocketInternalMetric{
-		StreamsStarted:                   t.streamsStarted,
-		StreamsSucceeded:                 t.streamsSucceeded,
-		StreamsFailed:                    t.streamsFailed,
-		MessagesSent:                     t.msgSent,
-		MessagesReceived:                 t.msgRecv,
-		KeepAlivesSent:                   t.kpCount,
-		LastRemoteStreamCreatedTimestamp: t.lastStreamCreated,
-		LastMessageSentTimestamp:         t.lastMsgSent,
-		LastMessageReceivedTimestamp:     t.lastMsgRecv,
+		StreamsStarted:                   atomic.LoadInt64(&t.czData.streamsStarted),
+		StreamsSucceeded:                 atomic.LoadInt64(&t.czData.streamsSucceeded),
+		StreamsFailed:                    atomic.LoadInt64(&t.czData.streamsFailed),
+		MessagesSent:                     atomic.LoadInt64(&t.czData.msgSent),
+		MessagesReceived:                 atomic.LoadInt64(&t.czData.msgRecv),
+		KeepAlivesSent:                   atomic.LoadInt64(&t.czData.kpCount),
+		LastRemoteStreamCreatedTimestamp: time.Unix(0, atomic.LoadInt64(&t.czData.lastStreamCreatedTime)),
+		LastMessageSentTimestamp:         time.Unix(0, atomic.LoadInt64(&t.czData.lastMsgSentTime)),
+		LastMessageReceivedTimestamp:     time.Unix(0, atomic.LoadInt64(&t.czData.lastMsgRecvTime)),
 		LocalFlowControlWindow:           int64(t.fc.getSize()),
 		SocketOptions:                    channelz.GetSocketOption(t.conn),
 		LocalAddr:                        t.localAddr,
@@ -1158,27 +1180,22 @@ func (t *http2Server) ChannelzMetric() *channelz.SocketInternalMetric {
 	if au, ok := t.authInfo.(credentials.ChannelzSecurityInfo); ok {
 		s.Security = au.GetSecurityValue()
 	}
-	t.czmu.RUnlock()
 	s.RemoteFlowControlWindow = t.getOutFlowWindow()
 	return &s
 }
 
 func (t *http2Server) IncrMsgSent() {
-	t.czmu.Lock()
-	t.msgSent++
-	t.lastMsgSent = time.Now()
-	t.czmu.Unlock()
+	atomic.AddInt64(&t.czData.msgSent, 1)
+	atomic.StoreInt64(&t.czData.lastMsgSentTime, time.Now().UnixNano())
 }
 
 func (t *http2Server) IncrMsgRecv() {
-	t.czmu.Lock()
-	t.msgRecv++
-	t.lastMsgRecv = time.Now()
-	t.czmu.Unlock()
+	atomic.AddInt64(&t.czData.msgRecv, 1)
+	atomic.StoreInt64(&t.czData.lastMsgRecvTime, time.Now().UnixNano())
 }
 
 func (t *http2Server) getOutFlowWindow() int64 {
-	resp := make(chan uint32)
+	resp := make(chan uint32, 1)
 	timer := time.NewTimer(time.Second)
 	defer timer.Stop()
 	t.controlBuf.put(&outFlowControlSizeRequest{resp})
diff --git a/vendor/google.golang.org/grpc/internal/transport/http_util.go b/vendor/google.golang.org/grpc/internal/transport/http_util.go
index 21da6e80..9d212867 100644
--- a/vendor/google.golang.org/grpc/internal/transport/http_util.go
+++ b/vendor/google.golang.org/grpc/internal/transport/http_util.go
@@ -24,6 +24,7 @@ import (
 	"encoding/base64"
 	"fmt"
 	"io"
+	"math"
 	"net"
 	"net/http"
 	"strconv"
@@ -77,7 +78,8 @@ var (
 		codes.ResourceExhausted: http2.ErrCodeEnhanceYourCalm,
 		codes.PermissionDenied:  http2.ErrCodeInadequateSecurity,
 	}
-	httpStatusConvTab = map[int]codes.Code{
+	// HTTPStatusConvTab is the HTTP status code to gRPC error code conversion table.
+	HTTPStatusConvTab = map[int]codes.Code{
 		// 400 Bad Request - INTERNAL.
 		http.StatusBadRequest: codes.Internal,
 		// 401 Unauthorized  - UNAUTHENTICATED.
@@ -97,9 +99,7 @@ var (
 	}
 )
 
-// Records the states during HPACK decoding. Must be reset once the
-// decoding of the entire headers are finished.
-type decodeState struct {
+type parsedHeaderData struct {
 	encoding string
 	// statusGen caches the stream status received from the trailer the server
 	// sent.  Client side only.  Do not access directly.  After all trailers are
@@ -119,8 +119,30 @@ type decodeState struct {
 	statsTags      []byte
 	statsTrace     []byte
 	contentSubtype string
+
+	// isGRPC field indicates whether the peer is speaking gRPC (otherwise HTTP).
+	//
+	// We are in gRPC mode (peer speaking gRPC) if:
+	// 	* We are client side and have already received a HEADER frame that indicates gRPC peer.
+	//  * The header contains valid  a content-type, i.e. a string starts with "application/grpc"
+	// And we should handle error specific to gRPC.
+	//
+	// Otherwise (i.e. a content-type string starts without "application/grpc", or does not exist), we
+	// are in HTTP fallback mode, and should handle error specific to HTTP.
+	isGRPC         bool
+	grpcErr        error
+	httpErr        error
+	contentTypeErr string
+}
+
+// decodeState configures decoding criteria and records the decoded data.
+type decodeState struct {
 	// whether decoding on server side or not
 	serverSide bool
+
+	// Records the states during HPACK decoding. It will be filled with info parsed from HTTP HEADERS
+	// frame once decodeHeader function has been invoked and returned.
+	data parsedHeaderData
 }
 
 // isReservedHeader checks whether hdr belongs to HTTP2 headers
@@ -201,11 +223,11 @@ func contentType(contentSubtype string) string {
 }
 
 func (d *decodeState) status() *status.Status {
-	if d.statusGen == nil {
+	if d.data.statusGen == nil {
 		// No status-details were provided; generate status using code/msg.
-		d.statusGen = status.New(codes.Code(int32(*(d.rawStatusCode))), d.rawStatusMsg)
+		d.data.statusGen = status.New(codes.Code(int32(*(d.data.rawStatusCode))), d.data.rawStatusMsg)
 	}
-	return d.statusGen
+	return d.data.statusGen
 }
 
 const binHdrSuffix = "-bin"
@@ -243,113 +265,146 @@ func (d *decodeState) decodeHeader(frame *http2.MetaHeadersFrame) error {
 	if frame.Truncated {
 		return status.Error(codes.Internal, "peer header list size exceeded limit")
 	}
+
 	for _, hf := range frame.Fields {
-		if err := d.processHeaderField(hf); err != nil {
-			return err
-		}
+		d.processHeaderField(hf)
 	}
 
-	if d.serverSide {
+	if d.data.isGRPC {
+		if d.data.grpcErr != nil {
+			return d.data.grpcErr
+		}
+		if d.serverSide {
+			return nil
+		}
+		if d.data.rawStatusCode == nil && d.data.statusGen == nil {
+			// gRPC status doesn't exist.
+			// Set rawStatusCode to be unknown and return nil error.
+			// So that, if the stream has ended this Unknown status
+			// will be propagated to the user.
+			// Otherwise, it will be ignored. In which case, status from
+			// a later trailer, that has StreamEnded flag set, is propagated.
+			code := int(codes.Unknown)
+			d.data.rawStatusCode = &code
+		}
 		return nil
 	}
 
-	// If grpc status exists, no need to check further.
-	if d.rawStatusCode != nil || d.statusGen != nil {
-		return nil
+	// HTTP fallback mode
+	if d.data.httpErr != nil {
+		return d.data.httpErr
 	}
 
-	// If grpc status doesn't exist and http status doesn't exist,
-	// then it's a malformed header.
-	if d.httpStatus == nil {
-		return status.Error(codes.Internal, "malformed header: doesn't contain status(gRPC or HTTP)")
-	}
+	var (
+		code = codes.Internal // when header does not include HTTP status, return INTERNAL
+		ok   bool
+	)
 
-	if *(d.httpStatus) != http.StatusOK {
-		code, ok := httpStatusConvTab[*(d.httpStatus)]
+	if d.data.httpStatus != nil {
+		code, ok = HTTPStatusConvTab[*(d.data.httpStatus)]
 		if !ok {
 			code = codes.Unknown
 		}
-		return status.Error(code, http.StatusText(*(d.httpStatus)))
-	}
-
-	// gRPC status doesn't exist and http status is OK.
-	// Set rawStatusCode to be unknown and return nil error.
-	// So that, if the stream has ended this Unknown status
-	// will be propagated to the user.
-	// Otherwise, it will be ignored. In which case, status from
-	// a later trailer, that has StreamEnded flag set, is propagated.
-	code := int(codes.Unknown)
-	d.rawStatusCode = &code
-	return nil
+	}
+
+	return status.Error(code, d.constructHTTPErrMsg())
+}
+
+// constructErrMsg constructs error message to be returned in HTTP fallback mode.
+// Format: HTTP status code and its corresponding message + content-type error message.
+func (d *decodeState) constructHTTPErrMsg() string {
+	var errMsgs []string
+
+	if d.data.httpStatus == nil {
+		errMsgs = append(errMsgs, "malformed header: missing HTTP status")
+	} else {
+		errMsgs = append(errMsgs, fmt.Sprintf("%s: HTTP status code %d", http.StatusText(*(d.data.httpStatus)), *d.data.httpStatus))
+	}
+
+	if d.data.contentTypeErr == "" {
+		errMsgs = append(errMsgs, "transport: missing content-type field")
+	} else {
+		errMsgs = append(errMsgs, d.data.contentTypeErr)
+	}
+
+	return strings.Join(errMsgs, "; ")
 }
 
 func (d *decodeState) addMetadata(k, v string) {
-	if d.mdata == nil {
-		d.mdata = make(map[string][]string)
+	if d.data.mdata == nil {
+		d.data.mdata = make(map[string][]string)
 	}
-	d.mdata[k] = append(d.mdata[k], v)
+	d.data.mdata[k] = append(d.data.mdata[k], v)
 }
 
-func (d *decodeState) processHeaderField(f hpack.HeaderField) error {
+func (d *decodeState) processHeaderField(f hpack.HeaderField) {
 	switch f.Name {
 	case "content-type":
 		contentSubtype, validContentType := contentSubtype(f.Value)
 		if !validContentType {
-			return status.Errorf(codes.Internal, "transport: received the unexpected content-type %q", f.Value)
+			d.data.contentTypeErr = fmt.Sprintf("transport: received the unexpected content-type %q", f.Value)
+			return
 		}
-		d.contentSubtype = contentSubtype
+		d.data.contentSubtype = contentSubtype
 		// TODO: do we want to propagate the whole content-type in the metadata,
 		// or come up with a way to just propagate the content-subtype if it was set?
 		// ie {"content-type": "application/grpc+proto"} or {"content-subtype": "proto"}
 		// in the metadata?
 		d.addMetadata(f.Name, f.Value)
+		d.data.isGRPC = true
 	case "grpc-encoding":
-		d.encoding = f.Value
+		d.data.encoding = f.Value
 	case "grpc-status":
 		code, err := strconv.Atoi(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-status: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status: %v", err)
+			return
 		}
-		d.rawStatusCode = &code
+		d.data.rawStatusCode = &code
 	case "grpc-message":
-		d.rawStatusMsg = decodeGrpcMessage(f.Value)
+		d.data.rawStatusMsg = decodeGrpcMessage(f.Value)
 	case "grpc-status-details-bin":
 		v, err := decodeBinHeader(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+			return
 		}
 		s := &spb.Status{}
 		if err := proto.Unmarshal(v, s); err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+			return
 		}
-		d.statusGen = status.FromProto(s)
+		d.data.statusGen = status.FromProto(s)
 	case "grpc-timeout":
-		d.timeoutSet = true
+		d.data.timeoutSet = true
 		var err error
-		if d.timeout, err = decodeTimeout(f.Value); err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed time-out: %v", err)
+		if d.data.timeout, err = decodeTimeout(f.Value); err != nil {
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed time-out: %v", err)
 		}
 	case ":path":
-		d.method = f.Value
+		d.data.method = f.Value
 	case ":status":
 		code, err := strconv.Atoi(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed http-status: %v", err)
+			d.data.httpErr = status.Errorf(codes.Internal, "transport: malformed http-status: %v", err)
+			return
 		}
-		d.httpStatus = &code
+		d.data.httpStatus = &code
 	case "grpc-tags-bin":
 		v, err := decodeBinHeader(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-tags-bin: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-tags-bin: %v", err)
+			return
 		}
-		d.statsTags = v
+		d.data.statsTags = v
 		d.addMetadata(f.Name, string(v))
 	case "grpc-trace-bin":
 		v, err := decodeBinHeader(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-trace-bin: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-trace-bin: %v", err)
+			return
 		}
-		d.statsTrace = v
+		d.data.statsTrace = v
 		d.addMetadata(f.Name, string(v))
 	default:
 		if isReservedHeader(f.Name) && !isWhitelistedHeader(f.Name) {
@@ -358,11 +413,10 @@ func (d *decodeState) processHeaderField(f hpack.HeaderField) error {
 		v, err := decodeMetadataHeader(f.Name, f.Value)
 		if err != nil {
 			errorf("Failed to decode metadata header (%q, %q): %v", f.Name, f.Value, err)
-			return nil
+			return
 		}
 		d.addMetadata(f.Name, v)
 	}
-	return nil
 }
 
 type timeoutUnit uint8
@@ -435,6 +489,10 @@ func decodeTimeout(s string) (time.Duration, error) {
 	if size < 2 {
 		return 0, fmt.Errorf("transport: timeout string is too short: %q", s)
 	}
+	if size > 9 {
+		// Spec allows for 8 digits plus the unit.
+		return 0, fmt.Errorf("transport: timeout string is too long: %q", s)
+	}
 	unit := timeoutUnit(s[size-1])
 	d, ok := timeoutUnitToDuration(unit)
 	if !ok {
@@ -444,6 +502,11 @@ func decodeTimeout(s string) (time.Duration, error) {
 	if err != nil {
 		return 0, err
 	}
+	const maxHours = math.MaxInt64 / int64(time.Hour)
+	if d == time.Hour && t > maxHours {
+		// This timeout would overflow math.MaxInt64; clamp it.
+		return time.Duration(math.MaxInt64), nil
+	}
 	return d * time.Duration(t), nil
 }
 
diff --git a/vendor/google.golang.org/grpc/internal/transport/log.go b/vendor/google.golang.org/grpc/internal/transport/log.go
index ac8e358c..879df80c 100644
--- a/vendor/google.golang.org/grpc/internal/transport/log.go
+++ b/vendor/google.golang.org/grpc/internal/transport/log.go
@@ -42,9 +42,3 @@ func errorf(format string, args ...interface{}) {
 		grpclog.Errorf(format, args...)
 	}
 }
-
-func fatalf(format string, args ...interface{}) {
-	if grpclog.V(logLevel) {
-		grpclog.Fatalf(format, args...)
-	}
-}
diff --git a/vendor/google.golang.org/grpc/internal/transport/transport.go b/vendor/google.golang.org/grpc/internal/transport/transport.go
index 9775eeb8..1c1d1067 100644
--- a/vendor/google.golang.org/grpc/internal/transport/transport.go
+++ b/vendor/google.golang.org/grpc/internal/transport/transport.go
@@ -22,6 +22,8 @@
 package transport
 
 import (
+	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -29,7 +31,6 @@ import (
 	"sync"
 	"sync/atomic"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/keepalive"
@@ -39,10 +40,32 @@ import (
 	"google.golang.org/grpc/tap"
 )
 
+type bufferPool struct {
+	pool sync.Pool
+}
+
+func newBufferPool() *bufferPool {
+	return &bufferPool{
+		pool: sync.Pool{
+			New: func() interface{} {
+				return new(bytes.Buffer)
+			},
+		},
+	}
+}
+
+func (p *bufferPool) get() *bytes.Buffer {
+	return p.pool.Get().(*bytes.Buffer)
+}
+
+func (p *bufferPool) put(b *bytes.Buffer) {
+	p.pool.Put(b)
+}
+
 // recvMsg represents the received msg from the transport. All transport
 // protocol specific info has been removed.
 type recvMsg struct {
-	data []byte
+	buffer *bytes.Buffer
 	// nil: received some data
 	// io.EOF: stream is completed. data is nil.
 	// other non-nil error: transport failure. data is nil.
@@ -110,15 +133,16 @@ func (b *recvBuffer) get() <-chan recvMsg {
 	return b.c
 }
 
-//
 // recvBufferReader implements io.Reader interface to read the data from
 // recvBuffer.
 type recvBufferReader struct {
-	ctx     context.Context
-	ctxDone <-chan struct{} // cache of ctx.Done() (for performance).
-	recv    *recvBuffer
-	last    []byte // Stores the remaining data in the previous calls.
-	err     error
+	closeStream func(error) // Closes the client transport stream with the given error and nil trailer metadata.
+	ctx         context.Context
+	ctxDone     <-chan struct{} // cache of ctx.Done() (for performance).
+	recv        *recvBuffer
+	last        *bytes.Buffer // Stores the remaining data in the previous calls.
+	err         error
+	freeBuffer  func(*bytes.Buffer)
 }
 
 // Read reads the next len(p) bytes from last. If last is drained, it tries to
@@ -128,31 +152,74 @@ func (r *recvBufferReader) Read(p []byte) (n int, err error) {
 	if r.err != nil {
 		return 0, r.err
 	}
-	n, r.err = r.read(p)
+	if r.last != nil {
+		// Read remaining data left in last call.
+		copied, _ := r.last.Read(p)
+		if r.last.Len() == 0 {
+			r.freeBuffer(r.last)
+			r.last = nil
+		}
+		return copied, nil
+	}
+	if r.closeStream != nil {
+		n, r.err = r.readClient(p)
+	} else {
+		n, r.err = r.read(p)
+	}
 	return n, r.err
 }
 
 func (r *recvBufferReader) read(p []byte) (n int, err error) {
-	if r.last != nil && len(r.last) > 0 {
-		// Read remaining data left in last call.
-		copied := copy(p, r.last)
-		r.last = r.last[copied:]
-		return copied, nil
-	}
 	select {
 	case <-r.ctxDone:
 		return 0, ContextErr(r.ctx.Err())
 	case m := <-r.recv.get():
-		r.recv.load()
-		if m.err != nil {
-			return 0, m.err
-		}
-		copied := copy(p, m.data)
-		r.last = m.data[copied:]
-		return copied, nil
+		return r.readAdditional(m, p)
+	}
+}
+
+func (r *recvBufferReader) readClient(p []byte) (n int, err error) {
+	// If the context is canceled, then closes the stream with nil metadata.
+	// closeStream writes its error parameter to r.recv as a recvMsg.
+	// r.readAdditional acts on that message and returns the necessary error.
+	select {
+	case <-r.ctxDone:
+		// Note that this adds the ctx error to the end of recv buffer, and
+		// reads from the head. This will delay the error until recv buffer is
+		// empty, thus will delay ctx cancellation in Recv().
+		//
+		// It's done this way to fix a race between ctx cancel and trailer. The
+		// race was, stream.Recv() may return ctx error if ctxDone wins the
+		// race, but stream.Trailer() may return a non-nil md because the stream
+		// was not marked as done when trailer is received. This closeStream
+		// call will mark stream as done, thus fix the race.
+		//
+		// TODO: delaying ctx error seems like a unnecessary side effect. What
+		// we really want is to mark the stream as done, and return ctx error
+		// faster.
+		r.closeStream(ContextErr(r.ctx.Err()))
+		m := <-r.recv.get()
+		return r.readAdditional(m, p)
+	case m := <-r.recv.get():
+		return r.readAdditional(m, p)
 	}
 }
 
+func (r *recvBufferReader) readAdditional(m recvMsg, p []byte) (n int, err error) {
+	r.recv.load()
+	if m.err != nil {
+		return 0, m.err
+	}
+	copied, _ := m.buffer.Read(p)
+	if m.buffer.Len() == 0 {
+		r.freeBuffer(m.buffer)
+		r.last = nil
+	} else {
+		r.last = m.buffer
+	}
+	return copied, nil
+}
+
 type streamState uint32
 
 const (
@@ -176,19 +243,22 @@ type Stream struct {
 	buf          *recvBuffer
 	trReader     io.Reader
 	fc           *inFlow
-	recvQuota    uint32
 	wq           *writeQuota
 
 	// Callback to state application's intentions to read data. This
 	// is used to adjust flow control, if needed.
 	requestRead func(int)
 
-	headerChan chan struct{} // closed to indicate the end of header metadata.
-	headerDone uint32        // set when headerChan is closed. Used to avoid closing headerChan multiple times.
+	headerChan       chan struct{} // closed to indicate the end of header metadata.
+	headerChanClosed uint32        // set when headerChan is closed. Used to avoid closing headerChan multiple times.
 
 	// hdrMu protects header and trailer metadata on the server-side.
-	hdrMu   sync.Mutex
-	header  metadata.MD // the received header metadata.
+	hdrMu sync.Mutex
+	// On client side, header keeps the received header metadata.
+	//
+	// On server side, header keeps the header set by SetHeader(). The complete
+	// header will merged into this after t.WriteHeader() is called.
+	header  metadata.MD
 	trailer metadata.MD // the key-value map of trailer metadata.
 
 	noHeaders bool // set if the client never received headers (set only after the stream is done).
@@ -241,6 +311,14 @@ func (s *Stream) waitOnHeader() error {
 	}
 	select {
 	case <-s.ctx.Done():
+		// We prefer success over failure when reading messages because we delay
+		// context error in stream.Read(). To keep behavior consistent, we also
+		// prefer success here.
+		select {
+		case <-s.headerChan:
+			return nil
+		default:
+		}
 		return ContextErr(s.ctx.Err())
 	case <-s.headerChan:
 		return nil
@@ -267,10 +345,19 @@ func (s *Stream) Done() <-chan struct{} {
 	return s.done
 }
 
-// Header acquires the key-value pairs of header metadata once it
-// is available. It blocks until i) the metadata is ready or ii) there is no
-// header metadata or iii) the stream is canceled/expired.
+// Header returns the header metadata of the stream.
+//
+// On client side, it acquires the key-value pairs of header metadata once it is
+// available. It blocks until i) the metadata is ready or ii) there is no header
+// metadata or iii) the stream is canceled/expired.
+//
+// On server side, it returns the out header after t.WriteHeader is called.
 func (s *Stream) Header() (metadata.MD, error) {
+	if s.headerChan == nil && s.header != nil {
+		// On server side, return the header in stream. It will be the out
+		// header after t.WriteHeader is called.
+		return s.header.Copy(), nil
+	}
 	err := s.waitOnHeader()
 	// Even if the stream is closed, header is returned if available.
 	select {
@@ -293,8 +380,7 @@ func (s *Stream) TrailersOnly() (bool, error) {
 	if err != nil {
 		return false, err
 	}
-	// if !headerDone, some other connection error occurred.
-	return s.noHeaders && atomic.LoadUint32(&s.headerDone) == 1, nil
+	return s.noHeaders, nil
 }
 
 // Trailer returns the cached trailer metedata. Note that if it is not called
@@ -466,8 +552,12 @@ type ConnectOptions struct {
 	FailOnNonTempDialError bool
 	// PerRPCCredentials stores the PerRPCCredentials required to issue RPCs.
 	PerRPCCredentials []credentials.PerRPCCredentials
-	// TransportCredentials stores the Authenticator required to setup a client connection.
+	// TransportCredentials stores the Authenticator required to setup a client
+	// connection. Only one of TransportCredentials and CredsBundle is non-nil.
 	TransportCredentials credentials.TransportCredentials
+	// CredsBundle is the credentials bundle to be used. Only one of
+	// TransportCredentials and CredsBundle is non-nil.
+	CredsBundle credentials.Bundle
 	// KeepaliveParams stores the keepalive parameters.
 	KeepaliveParams keepalive.ClientParameters
 	// StatsHandler stores the handler for stats.
@@ -495,8 +585,8 @@ type TargetInfo struct {
 
 // NewClientTransport establishes the transport with the required ConnectOptions
 // and returns it to the caller.
-func NewClientTransport(connectCtx, ctx context.Context, target TargetInfo, opts ConnectOptions, onSuccess func()) (ClientTransport, error) {
-	return newHTTP2Client(connectCtx, ctx, target, opts, onSuccess)
+func NewClientTransport(connectCtx, ctx context.Context, target TargetInfo, opts ConnectOptions, onPrefaceReceipt func(), onGoAway func(GoAwayReason), onClose func()) (ClientTransport, error) {
+	return newHTTP2Client(connectCtx, ctx, target, opts, onPrefaceReceipt, onGoAway, onClose)
 }
 
 // Options provides additional hints and information for message
@@ -541,9 +631,12 @@ type ClientTransport interface {
 	// is called only once.
 	Close() error
 
-	// GracefulClose starts to tear down the transport. It stops accepting
-	// new RPCs and wait the completion of the pending RPCs.
-	GracefulClose() error
+	// GracefulClose starts to tear down the transport: the transport will stop
+	// accepting new RPCs and NewStream will return error. Once all streams are
+	// finished, the transport will close.
+	//
+	// It does not block.
+	GracefulClose()
 
 	// Write sends the data for the given stream. A nil stream indicates
 	// the write is to be performed on the transport as a whole.
@@ -573,6 +666,9 @@ type ClientTransport interface {
 	// GetGoAwayReason returns the reason why GoAway frame was received.
 	GetGoAwayReason() GoAwayReason
 
+	// RemoteAddr returns the remote network address.
+	RemoteAddr() net.Addr
+
 	// IncrMsgSent increments the number of message sent through this transport.
 	IncrMsgSent()
 
@@ -683,3 +779,38 @@ const (
 	// "too_many_pings".
 	GoAwayTooManyPings GoAwayReason = 2
 )
+
+// channelzData is used to store channelz related data for http2Client and http2Server.
+// These fields cannot be embedded in the original structs (e.g. http2Client), since to do atomic
+// operation on int64 variable on 32-bit machine, user is responsible to enforce memory alignment.
+// Here, by grouping those int64 fields inside a struct, we are enforcing the alignment.
+type channelzData struct {
+	kpCount int64
+	// The number of streams that have started, including already finished ones.
+	streamsStarted int64
+	// Client side: The number of streams that have ended successfully by receiving
+	// EoS bit set frame from server.
+	// Server side: The number of streams that have ended successfully by sending
+	// frame with EoS bit set.
+	streamsSucceeded int64
+	streamsFailed    int64
+	// lastStreamCreatedTime stores the timestamp that the last stream gets created. It is of int64 type
+	// instead of time.Time since it's more costly to atomically update time.Time variable than int64
+	// variable. The same goes for lastMsgSentTime and lastMsgRecvTime.
+	lastStreamCreatedTime int64
+	msgSent               int64
+	msgRecv               int64
+	lastMsgSentTime       int64
+	lastMsgRecvTime       int64
+}
+
+// ContextErr converts the error from context package into a status error.
+func ContextErr(err error) error {
+	switch err {
+	case context.DeadlineExceeded:
+		return status.Error(codes.DeadlineExceeded, err.Error())
+	case context.Canceled:
+		return status.Error(codes.Canceled, err.Error())
+	}
+	return status.Errorf(codes.Internal, "Unexpected error from context packet: %v", err)
+}
diff --git a/vendor/google.golang.org/grpc/keepalive/keepalive.go b/vendor/google.golang.org/grpc/keepalive/keepalive.go
index f8adc7e6..34d31b5e 100644
--- a/vendor/google.golang.org/grpc/keepalive/keepalive.go
+++ b/vendor/google.golang.org/grpc/keepalive/keepalive.go
@@ -16,7 +16,8 @@
  *
  */
 
-// Package keepalive defines configurable parameters for point-to-point healthcheck.
+// Package keepalive defines configurable parameters for point-to-point
+// healthcheck.
 package keepalive
 
 import (
@@ -24,42 +25,61 @@ import (
 )
 
 // ClientParameters is used to set keepalive parameters on the client-side.
-// These configure how the client will actively probe to notice when a connection is broken
-// and send pings so intermediaries will be aware of the liveness of the connection.
-// Make sure these parameters are set in coordination with the keepalive policy on the server,
-// as incompatible settings can result in closing of connection.
+// These configure how the client will actively probe to notice when a
+// connection is broken and send pings so intermediaries will be aware of the
+// liveness of the connection. Make sure these parameters are set in
+// coordination with the keepalive policy on the server, as incompatible
+// settings can result in closing of connection.
 type ClientParameters struct {
-	// After a duration of this time if the client doesn't see any activity it pings the server to see if the transport is still alive.
+	// After a duration of this time if the client doesn't see any activity it
+	// pings the server to see if the transport is still alive.
+	// If set below 10s, a minimum value of 10s will be used instead.
 	Time time.Duration // The current default value is infinity.
-	// After having pinged for keepalive check, the client waits for a duration of Timeout and if no activity is seen even after that
-	// the connection is closed.
+	// After having pinged for keepalive check, the client waits for a duration
+	// of Timeout and if no activity is seen even after that the connection is
+	// closed.
 	Timeout time.Duration // The current default value is 20 seconds.
-	// If true, client runs keepalive checks even with no active RPCs.
+	// If true, client sends keepalive pings even with no active RPCs. If false,
+	// when there are no active RPCs, Time and Timeout will be ignored and no
+	// keepalive pings will be sent.
 	PermitWithoutStream bool // false by default.
 }
 
-// ServerParameters is used to set keepalive and max-age parameters on the server-side.
+// ServerParameters is used to set keepalive and max-age parameters on the
+// server-side.
 type ServerParameters struct {
-	// MaxConnectionIdle is a duration for the amount of time after which an idle connection would be closed by sending a GoAway.
-	// Idleness duration is defined since the most recent time the number of outstanding RPCs became zero or the connection establishment.
+	// MaxConnectionIdle is a duration for the amount of time after which an
+	// idle connection would be closed by sending a GoAway. Idleness duration is
+	// defined since the most recent time the number of outstanding RPCs became
+	// zero or the connection establishment.
 	MaxConnectionIdle time.Duration // The current default value is infinity.
-	// MaxConnectionAge is a duration for the maximum amount of time a connection may exist before it will be closed by sending a GoAway.
-	// A random jitter of +/-10% will be added to MaxConnectionAge to spread out connection storms.
+	// MaxConnectionAge is a duration for the maximum amount of time a
+	// connection may exist before it will be closed by sending a GoAway. A
+	// random jitter of +/-10% will be added to MaxConnectionAge to spread out
+	// connection storms.
 	MaxConnectionAge time.Duration // The current default value is infinity.
-	// MaxConnectinoAgeGrace is an additive period after MaxConnectionAge after which the connection will be forcibly closed.
+	// MaxConnectionAgeGrace is an additive period after MaxConnectionAge after
+	// which the connection will be forcibly closed.
 	MaxConnectionAgeGrace time.Duration // The current default value is infinity.
-	// After a duration of this time if the server doesn't see any activity it pings the client to see if the transport is still alive.
+	// After a duration of this time if the server doesn't see any activity it
+	// pings the client to see if the transport is still alive.
+	// If set below 1s, a minimum value of 1s will be used instead.
 	Time time.Duration // The current default value is 2 hours.
-	// After having pinged for keepalive check, the server waits for a duration of Timeout and if no activity is seen even after that
-	// the connection is closed.
+	// After having pinged for keepalive check, the server waits for a duration
+	// of Timeout and if no activity is seen even after that the connection is
+	// closed.
 	Timeout time.Duration // The current default value is 20 seconds.
 }
 
-// EnforcementPolicy is used to set keepalive enforcement policy on the server-side.
-// Server will close connection with a client that violates this policy.
+// EnforcementPolicy is used to set keepalive enforcement policy on the
+// server-side. Server will close connection with a client that violates this
+// policy.
 type EnforcementPolicy struct {
-	// MinTime is the minimum amount of time a client should wait before sending a keepalive ping.
+	// MinTime is the minimum amount of time a client should wait before sending
+	// a keepalive ping.
 	MinTime time.Duration // The current default value is 5 minutes.
-	// If true, server expects keepalive pings even when there are no active streams(RPCs).
+	// If true, server allows keepalive pings even when there are no active
+	// streams(RPCs). If false, and client sends ping when there are no active
+	// streams, server will send GOAWAY and close the connection.
 	PermitWithoutStream bool // false by default.
 }
diff --git a/vendor/google.golang.org/grpc/metadata/metadata.go b/vendor/google.golang.org/grpc/metadata/metadata.go
index bd2eaf40..cf6d1b94 100644
--- a/vendor/google.golang.org/grpc/metadata/metadata.go
+++ b/vendor/google.golang.org/grpc/metadata/metadata.go
@@ -22,10 +22,9 @@
 package metadata // import "google.golang.org/grpc/metadata"
 
 import (
+	"context"
 	"fmt"
 	"strings"
-
-	"golang.org/x/net/context"
 )
 
 // DecodeKeyValue returns k, v, nil.
diff --git a/vendor/google.golang.org/grpc/naming/dns_resolver.go b/vendor/google.golang.org/grpc/naming/dns_resolver.go
index 0f8a908e..c9f79dc5 100644
--- a/vendor/google.golang.org/grpc/naming/dns_resolver.go
+++ b/vendor/google.golang.org/grpc/naming/dns_resolver.go
@@ -19,13 +19,13 @@
 package naming
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"net"
 	"strconv"
 	"time"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/grpclog"
 )
 
@@ -37,6 +37,9 @@ const (
 var (
 	errMissingAddr  = errors.New("missing address")
 	errWatcherClose = errors.New("watcher has been closed")
+
+	lookupHost = net.DefaultResolver.LookupHost
+	lookupSRV  = net.DefaultResolver.LookupSRV
 )
 
 // NewDNSResolverWithFreq creates a DNS Resolver that can resolve DNS names, and
@@ -73,8 +76,8 @@ func formatIP(addr string) (addrIP string, ok bool) {
 
 // parseTarget takes the user input target string, returns formatted host and port info.
 // If target doesn't specify a port, set the port to be the defaultPort.
-// If target is in IPv6 format and host-name is enclosed in sqarue brackets, brackets
-// are strippd when setting the host.
+// If target is in IPv6 format and host-name is enclosed in square brackets, brackets
+// are stripped when setting the host.
 // examples:
 // target: "www.google.com" returns host: "www.google.com", port: "443"
 // target: "ipv4-host:80" returns host: "ipv4-host", port: "80"
@@ -218,7 +221,7 @@ func (w *dnsWatcher) lookupSRV() map[string]*Update {
 	for _, s := range srvs {
 		lbAddrs, err := lookupHost(w.ctx, s.Target)
 		if err != nil {
-			grpclog.Warningf("grpc: failed load banlacer address dns lookup due to %v.\n", err)
+			grpclog.Warningf("grpc: failed load balancer address dns lookup due to %v.\n", err)
 			continue
 		}
 		for _, a := range lbAddrs {
diff --git a/vendor/google.golang.org/grpc/naming/go17.go b/vendor/google.golang.org/grpc/naming/go17.go
deleted file mode 100644
index 57b65d7b..00000000
--- a/vendor/google.golang.org/grpc/naming/go17.go
+++ /dev/null
@@ -1,34 +0,0 @@
-// +build go1.6,!go1.8
-
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package naming
-
-import (
-	"net"
-
-	"golang.org/x/net/context"
-)
-
-var (
-	lookupHost = func(ctx context.Context, host string) ([]string, error) { return net.LookupHost(host) }
-	lookupSRV  = func(ctx context.Context, service, proto, name string) (string, []*net.SRV, error) {
-		return net.LookupSRV(service, proto, name)
-	}
-)
diff --git a/vendor/google.golang.org/grpc/naming/naming.go b/vendor/google.golang.org/grpc/naming/naming.go
index 8cc39e93..f4c1c8b6 100644
--- a/vendor/google.golang.org/grpc/naming/naming.go
+++ b/vendor/google.golang.org/grpc/naming/naming.go
@@ -17,9 +17,8 @@
  */
 
 // Package naming defines the naming API and related data structures for gRPC.
-// The interface is EXPERIMENTAL and may be suject to change.
 //
-// Deprecated: please use package resolver.
+// This package is deprecated: please use package resolver instead.
 package naming
 
 // Operation defines the corresponding operations for a name resolution change.
diff --git a/vendor/google.golang.org/grpc/peer/peer.go b/vendor/google.golang.org/grpc/peer/peer.go
index 317b8b9d..e01d219f 100644
--- a/vendor/google.golang.org/grpc/peer/peer.go
+++ b/vendor/google.golang.org/grpc/peer/peer.go
@@ -21,9 +21,9 @@
 package peer
 
 import (
+	"context"
 	"net"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/credentials"
 )
 
diff --git a/vendor/google.golang.org/grpc/picker_wrapper.go b/vendor/google.golang.org/grpc/picker_wrapper.go
index 76cc456a..45baa2ae 100644
--- a/vendor/google.golang.org/grpc/picker_wrapper.go
+++ b/vendor/google.golang.org/grpc/picker_wrapper.go
@@ -19,10 +19,10 @@
 package grpc
 
 import (
+	"context"
 	"io"
 	"sync"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/balancer"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/grpclog"
@@ -101,10 +101,7 @@ func doneChannelzWrapper(acw *acBalancerWrapper, done func(balancer.DoneInfo)) f
 // - the subConn returned by the current picker is not READY
 // When one of these situations happens, pick blocks until the picker gets updated.
 func (bp *pickerWrapper) pick(ctx context.Context, failfast bool, opts balancer.PickOptions) (transport.ClientTransport, func(balancer.DoneInfo), error) {
-	var (
-		p  balancer.Picker
-		ch chan struct{}
-	)
+	var ch chan struct{}
 
 	for {
 		bp.mu.Lock()
@@ -123,6 +120,14 @@ func (bp *pickerWrapper) pick(ctx context.Context, failfast bool, opts balancer.
 			bp.mu.Unlock()
 			select {
 			case <-ctx.Done():
+				if connectionErr := bp.connectionError(); connectionErr != nil {
+					switch ctx.Err() {
+					case context.DeadlineExceeded:
+						return nil, nil, status.Errorf(codes.DeadlineExceeded, "latest connection error: %v", connectionErr)
+					case context.Canceled:
+						return nil, nil, status.Errorf(codes.Canceled, "latest connection error: %v", connectionErr)
+					}
+				}
 				return nil, nil, ctx.Err()
 			case <-ch:
 			}
@@ -130,7 +135,7 @@ func (bp *pickerWrapper) pick(ctx context.Context, failfast bool, opts balancer.
 		}
 
 		ch = bp.blockingCh
-		p = bp.picker
+		p := bp.picker
 		bp.mu.Unlock()
 
 		subConn, done, err := p.Pick(ctx, opts)
@@ -144,15 +149,22 @@ func (bp *pickerWrapper) pick(ctx context.Context, failfast bool, opts balancer.
 					continue
 				}
 				return nil, nil, status.Errorf(codes.Unavailable, "%v, latest connection error: %v", err, bp.connectionError())
+			case context.DeadlineExceeded:
+				return nil, nil, status.Error(codes.DeadlineExceeded, err.Error())
+			case context.Canceled:
+				return nil, nil, status.Error(codes.Canceled, err.Error())
 			default:
+				if _, ok := status.FromError(err); ok {
+					return nil, nil, err
+				}
 				// err is some other error.
-				return nil, nil, toRPCErr(err)
+				return nil, nil, status.Error(codes.Unknown, err.Error())
 			}
 		}
 
 		acw, ok := subConn.(*acBalancerWrapper)
 		if !ok {
-			grpclog.Infof("subconn returned from pick is not *acBalancerWrapper")
+			grpclog.Error("subconn returned from pick is not *acBalancerWrapper")
 			continue
 		}
 		if t, ok := acw.getAddrConn().getReadyTransport(); ok {
@@ -161,6 +173,11 @@ func (bp *pickerWrapper) pick(ctx context.Context, failfast bool, opts balancer.
 			}
 			return t, done, nil
 		}
+		if done != nil {
+			// Calling done with nil error, no bytes sent and no bytes received.
+			// DoneInfo with default value works.
+			done(balancer.DoneInfo{})
+		}
 		grpclog.Infof("blockingPicker: the picked transport is not ready, loop back to repick")
 		// If ok == false, ac.state is not READY.
 		// A valid picker always returns READY subConn. This means the state of ac
diff --git a/vendor/google.golang.org/grpc/pickfirst.go b/vendor/google.golang.org/grpc/pickfirst.go
index bf659d49..ed05b02e 100644
--- a/vendor/google.golang.org/grpc/pickfirst.go
+++ b/vendor/google.golang.org/grpc/pickfirst.go
@@ -19,7 +19,8 @@
 package grpc
 
 import (
-	"golang.org/x/net/context"
+	"context"
+
 	"google.golang.org/grpc/balancer"
 	"google.golang.org/grpc/connectivity"
 	"google.golang.org/grpc/grpclog"
@@ -50,13 +51,18 @@ type pickfirstBalancer struct {
 
 func (b *pickfirstBalancer) HandleResolvedAddrs(addrs []resolver.Address, err error) {
 	if err != nil {
-		grpclog.Infof("pickfirstBalancer: HandleResolvedAddrs called with error %v", err)
+		if grpclog.V(2) {
+			grpclog.Infof("pickfirstBalancer: HandleResolvedAddrs called with error %v", err)
+		}
 		return
 	}
 	if b.sc == nil {
 		b.sc, err = b.cc.NewSubConn(addrs, balancer.NewSubConnOptions{})
 		if err != nil {
-			grpclog.Errorf("pickfirstBalancer: failed to NewSubConn: %v", err)
+			//TODO(yuxuanli): why not change the cc state to Idle?
+			if grpclog.V(2) {
+				grpclog.Errorf("pickfirstBalancer: failed to NewSubConn: %v", err)
+			}
 			return
 		}
 		b.cc.UpdateBalancerState(connectivity.Idle, &picker{sc: b.sc})
@@ -68,9 +74,13 @@ func (b *pickfirstBalancer) HandleResolvedAddrs(addrs []resolver.Address, err er
 }
 
 func (b *pickfirstBalancer) HandleSubConnStateChange(sc balancer.SubConn, s connectivity.State) {
-	grpclog.Infof("pickfirstBalancer: HandleSubConnStateChange: %p, %v", sc, s)
+	if grpclog.V(2) {
+		grpclog.Infof("pickfirstBalancer: HandleSubConnStateChange: %p, %v", sc, s)
+	}
 	if b.sc != sc {
-		grpclog.Infof("pickfirstBalancer: ignored state change because sc is not recognized")
+		if grpclog.V(2) {
+			grpclog.Infof("pickfirstBalancer: ignored state change because sc is not recognized")
+		}
 		return
 	}
 	if s == connectivity.Shutdown {
diff --git a/vendor/google.golang.org/grpc/preloader.go b/vendor/google.golang.org/grpc/preloader.go
new file mode 100644
index 00000000..76acbbcc
--- /dev/null
+++ b/vendor/google.golang.org/grpc/preloader.go
@@ -0,0 +1,64 @@
+/*
+ *
+ * Copyright 2019 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpc
+
+import (
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// PreparedMsg is responsible for creating a Marshalled and Compressed object.
+//
+// This API is EXPERIMENTAL.
+type PreparedMsg struct {
+	// Struct for preparing msg before sending them
+	encodedData []byte
+	hdr         []byte
+	payload     []byte
+}
+
+// Encode marshalls and compresses the message using the codec and compressor for the stream.
+func (p *PreparedMsg) Encode(s Stream, msg interface{}) error {
+	ctx := s.Context()
+	rpcInfo, ok := rpcInfoFromContext(ctx)
+	if !ok {
+		return status.Errorf(codes.Internal, "grpc: unable to get rpcInfo")
+	}
+
+	// check if the context has the relevant information to prepareMsg
+	if rpcInfo.preloaderInfo == nil {
+		return status.Errorf(codes.Internal, "grpc: rpcInfo.preloaderInfo is nil")
+	}
+	if rpcInfo.preloaderInfo.codec == nil {
+		return status.Errorf(codes.Internal, "grpc: rpcInfo.preloaderInfo.codec is nil")
+	}
+
+	// prepare the msg
+	data, err := encode(rpcInfo.preloaderInfo.codec, msg)
+	if err != nil {
+		return err
+	}
+	p.encodedData = data
+	compData, err := compress(data, rpcInfo.preloaderInfo.cp, rpcInfo.preloaderInfo.comp)
+	if err != nil {
+		return err
+	}
+	p.hdr, p.payload = msgHeader(data, compData)
+	return nil
+}
diff --git a/vendor/google.golang.org/grpc/proxy.go b/vendor/google.golang.org/grpc/proxy.go
index 2d40236e..f8f69bfb 100644
--- a/vendor/google.golang.org/grpc/proxy.go
+++ b/vendor/google.golang.org/grpc/proxy.go
@@ -20,6 +20,8 @@ package grpc
 
 import (
 	"bufio"
+	"context"
+	"encoding/base64"
 	"errors"
 	"fmt"
 	"io"
@@ -27,10 +29,10 @@ import (
 	"net/http"
 	"net/http/httputil"
 	"net/url"
-
-	"golang.org/x/net/context"
 )
 
+const proxyAuthHeaderKey = "Proxy-Authorization"
+
 var (
 	// errDisabled indicates that proxy is disabled for the address.
 	errDisabled = errors.New("proxy is disabled for the address")
@@ -38,7 +40,7 @@ var (
 	httpProxyFromEnvironment = http.ProxyFromEnvironment
 )
 
-func mapAddress(ctx context.Context, address string) (string, error) {
+func mapAddress(ctx context.Context, address string) (*url.URL, error) {
 	req := &http.Request{
 		URL: &url.URL{
 			Scheme: "https",
@@ -47,12 +49,12 @@ func mapAddress(ctx context.Context, address string) (string, error) {
 	}
 	url, err := httpProxyFromEnvironment(req)
 	if err != nil {
-		return "", err
+		return nil, err
 	}
 	if url == nil {
-		return "", errDisabled
+		return nil, errDisabled
 	}
-	return url.Host, nil
+	return url, nil
 }
 
 // To read a response from a net.Conn, http.ReadResponse() takes a bufio.Reader.
@@ -69,18 +71,28 @@ func (c *bufConn) Read(b []byte) (int, error) {
 	return c.r.Read(b)
 }
 
-func doHTTPConnectHandshake(ctx context.Context, conn net.Conn, addr string) (_ net.Conn, err error) {
+func basicAuth(username, password string) string {
+	auth := username + ":" + password
+	return base64.StdEncoding.EncodeToString([]byte(auth))
+}
+
+func doHTTPConnectHandshake(ctx context.Context, conn net.Conn, backendAddr string, proxyURL *url.URL) (_ net.Conn, err error) {
 	defer func() {
 		if err != nil {
 			conn.Close()
 		}
 	}()
 
-	req := (&http.Request{
+	req := &http.Request{
 		Method: http.MethodConnect,
-		URL:    &url.URL{Host: addr},
+		URL:    &url.URL{Host: backendAddr},
 		Header: map[string][]string{"User-Agent": {grpcUA}},
-	})
+	}
+	if t := proxyURL.User; t != nil {
+		u := t.Username()
+		p, _ := t.Password()
+		req.Header.Add(proxyAuthHeaderKey, "Basic "+basicAuth(u, p))
+	}
 
 	if err := sendHTTPRequest(ctx, req, conn); err != nil {
 		return nil, fmt.Errorf("failed to write the HTTP request: %v", err)
@@ -108,23 +120,33 @@ func doHTTPConnectHandshake(ctx context.Context, conn net.Conn, addr string) (_
 // provided dialer, does HTTP CONNECT handshake and returns the connection.
 func newProxyDialer(dialer func(context.Context, string) (net.Conn, error)) func(context.Context, string) (net.Conn, error) {
 	return func(ctx context.Context, addr string) (conn net.Conn, err error) {
-		var skipHandshake bool
-		newAddr, err := mapAddress(ctx, addr)
+		var newAddr string
+		proxyURL, err := mapAddress(ctx, addr)
 		if err != nil {
 			if err != errDisabled {
 				return nil, err
 			}
-			skipHandshake = true
 			newAddr = addr
+		} else {
+			newAddr = proxyURL.Host
 		}
 
 		conn, err = dialer(ctx, newAddr)
 		if err != nil {
 			return
 		}
-		if !skipHandshake {
-			conn, err = doHTTPConnectHandshake(ctx, conn, addr)
+		if proxyURL != nil {
+			// proxy is disabled if proxyURL is nil.
+			conn, err = doHTTPConnectHandshake(ctx, conn, addr, proxyURL)
 		}
 		return
 	}
 }
+
+func sendHTTPRequest(ctx context.Context, req *http.Request, conn net.Conn) error {
+	req = req.WithContext(ctx)
+	if err := req.Write(conn); err != nil {
+		return fmt.Errorf("failed to write the HTTP request: %v", err)
+	}
+	return nil
+}
diff --git a/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go b/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
index 084bdbfe..297492e8 100644
--- a/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
+++ b/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2017 gRPC authors.
+ * Copyright 2018 gRPC authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,6 +21,7 @@
 package dns
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -31,7 +32,6 @@ import (
 	"sync"
 	"time"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal/backoff"
 	"google.golang.org/grpc/internal/grpcrand"
@@ -43,9 +43,12 @@ func init() {
 }
 
 const (
-	defaultPort = "443"
-	defaultFreq = time.Minute * 30
-	golang      = "GO"
+	defaultPort       = "443"
+	defaultFreq       = time.Minute * 30
+	defaultDNSSvrPort = "53"
+	golang            = "GO"
+	// txtPrefix is the prefix string to be prepended to the host name for txt record lookup.
+	txtPrefix = "_grpc_config."
 	// In DNS, service config is encoded in a TXT record via the mechanism
 	// described in RFC-1464 using the attribute name grpc_config.
 	txtAttribute = "grpc_config="
@@ -61,6 +64,34 @@ var (
 	errEndsWithColon = errors.New("dns resolver: missing port after port-separator colon")
 )
 
+var (
+	defaultResolver netResolver = net.DefaultResolver
+	// To prevent excessive re-resolution, we enforce a rate limit on DNS
+	// resolution requests.
+	minDNSResRate = 30 * time.Second
+)
+
+var customAuthorityDialler = func(authority string) func(ctx context.Context, network, address string) (net.Conn, error) {
+	return func(ctx context.Context, network, address string) (net.Conn, error) {
+		var dialer net.Dialer
+		return dialer.DialContext(ctx, network, authority)
+	}
+}
+
+var customAuthorityResolver = func(authority string) (netResolver, error) {
+	host, port, err := parseTarget(authority, defaultDNSSvrPort)
+	if err != nil {
+		return nil, err
+	}
+
+	authorityWithPort := net.JoinHostPort(host, port)
+
+	return &net.Resolver{
+		PreferGo: true,
+		Dial:     customAuthorityDialler(authorityWithPort),
+	}, nil
+}
+
 // NewBuilder creates a dnsBuilder which is used to factory DNS resolvers.
 func NewBuilder() resolver.Builder {
 	return &dnsBuilder{minFreq: defaultFreq}
@@ -73,10 +104,7 @@ type dnsBuilder struct {
 
 // Build creates and starts a DNS resolver that watches the name resolution of the target.
 func (b *dnsBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOption) (resolver.Resolver, error) {
-	if target.Authority != "" {
-		return nil, fmt.Errorf("Default DNS resolver does not support custom DNS server")
-	}
-	host, port, err := parseTarget(target.Endpoint)
+	host, port, err := parseTarget(target.Endpoint, defaultPort)
 	if err != nil {
 		return nil, err
 	}
@@ -111,6 +139,15 @@ func (b *dnsBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts
 		disableServiceConfig: opts.DisableServiceConfig,
 	}
 
+	if target.Authority == "" {
+		d.resolver = defaultResolver
+	} else {
+		d.resolver, err = customAuthorityResolver(target.Authority)
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	d.wg.Add(1)
 	go d.watcher()
 	return d, nil
@@ -121,6 +158,12 @@ func (b *dnsBuilder) Scheme() string {
 	return "dns"
 }
 
+type netResolver interface {
+	LookupHost(ctx context.Context, host string) (addrs []string, err error)
+	LookupSRV(ctx context.Context, service, proto, name string) (cname string, addrs []*net.SRV, err error)
+	LookupTXT(ctx context.Context, name string) (txts []string, err error)
+}
+
 // ipResolver watches for the name resolution update for an IP address.
 type ipResolver struct {
 	cc resolver.ClientConn
@@ -161,6 +204,7 @@ type dnsResolver struct {
 	retryCount int
 	host       string
 	port       string
+	resolver   netResolver
 	ctx        context.Context
 	cancel     context.CancelFunc
 	cc         resolver.ClientConn
@@ -200,7 +244,13 @@ func (d *dnsResolver) watcher() {
 			return
 		case <-d.t.C:
 		case <-d.rn:
+			if !d.t.Stop() {
+				// Before resetting a timer, it should be stopped to prevent racing with
+				// reads on it's channel.
+				<-d.t.C
+			}
 		}
+
 		result, sc := d.lookup()
 		// Next lookup should happen within an interval defined by d.freq. It may be
 		// more often due to exponential retry on empty address list.
@@ -213,18 +263,28 @@ func (d *dnsResolver) watcher() {
 		}
 		d.cc.NewServiceConfig(sc)
 		d.cc.NewAddress(result)
+
+		// Sleep to prevent excessive re-resolutions. Incoming resolution requests
+		// will be queued in d.rn.
+		t := time.NewTimer(minDNSResRate)
+		select {
+		case <-t.C:
+		case <-d.ctx.Done():
+			t.Stop()
+			return
+		}
 	}
 }
 
 func (d *dnsResolver) lookupSRV() []resolver.Address {
 	var newAddrs []resolver.Address
-	_, srvs, err := lookupSRV(d.ctx, "grpclb", "tcp", d.host)
+	_, srvs, err := d.resolver.LookupSRV(d.ctx, "grpclb", "tcp", d.host)
 	if err != nil {
 		grpclog.Infof("grpc: failed dns SRV record lookup due to %v.\n", err)
 		return nil
 	}
 	for _, s := range srvs {
-		lbAddrs, err := lookupHost(d.ctx, s.Target)
+		lbAddrs, err := d.resolver.LookupHost(d.ctx, s.Target)
 		if err != nil {
 			grpclog.Infof("grpc: failed load balancer address dns lookup due to %v.\n", err)
 			continue
@@ -243,7 +303,7 @@ func (d *dnsResolver) lookupSRV() []resolver.Address {
 }
 
 func (d *dnsResolver) lookupTXT() string {
-	ss, err := lookupTXT(d.ctx, d.host)
+	ss, err := d.resolver.LookupTXT(d.ctx, txtPrefix+d.host)
 	if err != nil {
 		grpclog.Infof("grpc: failed dns TXT record lookup due to %v.\n", err)
 		return ""
@@ -263,7 +323,7 @@ func (d *dnsResolver) lookupTXT() string {
 
 func (d *dnsResolver) lookupHost() []resolver.Address {
 	var newAddrs []resolver.Address
-	addrs, err := lookupHost(d.ctx, d.host)
+	addrs, err := d.resolver.LookupHost(d.ctx, d.host)
 	if err != nil {
 		grpclog.Warningf("grpc: failed dns A record lookup due to %v.\n", err)
 		return nil
@@ -305,16 +365,16 @@ func formatIP(addr string) (addrIP string, ok bool) {
 	return "[" + addr + "]", true
 }
 
-// parseTarget takes the user input target string, returns formatted host and port info.
+// parseTarget takes the user input target string and default port, returns formatted host and port info.
 // If target doesn't specify a port, set the port to be the defaultPort.
-// If target is in IPv6 format and host-name is enclosed in sqarue brackets, brackets
-// are strippd when setting the host.
+// If target is in IPv6 format and host-name is enclosed in square brackets, brackets
+// are stripped when setting the host.
 // examples:
-// target: "www.google.com" returns host: "www.google.com", port: "443"
-// target: "ipv4-host:80" returns host: "ipv4-host", port: "80"
-// target: "[ipv6-host]" returns host: "ipv6-host", port: "443"
-// target: ":80" returns host: "localhost", port: "80"
-func parseTarget(target string) (host, port string, err error) {
+// target: "www.google.com" defaultPort: "443" returns host: "www.google.com", port: "443"
+// target: "ipv4-host:80" defaultPort: "443" returns host: "ipv4-host", port: "80"
+// target: "[ipv6-host]" defaultPort: "443" returns host: "ipv6-host", port: "443"
+// target: ":80" defaultPort: "443" returns host: "localhost", port: "80"
+func parseTarget(target, defaultPort string) (host, port string, err error) {
 	if target == "" {
 		return "", "", errMissingAddr
 	}
diff --git a/vendor/google.golang.org/grpc/resolver/dns/go17.go b/vendor/google.golang.org/grpc/resolver/dns/go17.go
deleted file mode 100644
index b466bc8f..00000000
--- a/vendor/google.golang.org/grpc/resolver/dns/go17.go
+++ /dev/null
@@ -1,35 +0,0 @@
-// +build go1.6, !go1.8
-
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package dns
-
-import (
-	"net"
-
-	"golang.org/x/net/context"
-)
-
-var (
-	lookupHost = func(ctx context.Context, host string) ([]string, error) { return net.LookupHost(host) }
-	lookupSRV  = func(ctx context.Context, service, proto, name string) (string, []*net.SRV, error) {
-		return net.LookupSRV(service, proto, name)
-	}
-	lookupTXT = func(ctx context.Context, name string) ([]string, error) { return net.LookupTXT(name) }
-)
diff --git a/vendor/google.golang.org/grpc/resolver/dns/go18.go b/vendor/google.golang.org/grpc/resolver/dns/go18.go
deleted file mode 100644
index fa34f14c..00000000
--- a/vendor/google.golang.org/grpc/resolver/dns/go18.go
+++ /dev/null
@@ -1,29 +0,0 @@
-// +build go1.8
-
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package dns
-
-import "net"
-
-var (
-	lookupHost = net.DefaultResolver.LookupHost
-	lookupSRV  = net.DefaultResolver.LookupSRV
-	lookupTXT  = net.DefaultResolver.LookupTXT
-)
diff --git a/vendor/google.golang.org/grpc/resolver/passthrough/passthrough.go b/vendor/google.golang.org/grpc/resolver/passthrough/passthrough.go
index b76010d7..893d5d12 100644
--- a/vendor/google.golang.org/grpc/resolver/passthrough/passthrough.go
+++ b/vendor/google.golang.org/grpc/resolver/passthrough/passthrough.go
@@ -45,7 +45,7 @@ type passthroughResolver struct {
 }
 
 func (r *passthroughResolver) start() {
-	r.cc.NewAddress([]resolver.Address{{Addr: r.target.Endpoint}})
+	r.cc.UpdateState(resolver.State{Addresses: []resolver.Address{{Addr: r.target.Endpoint}}})
 }
 
 func (*passthroughResolver) ResolveNow(o resolver.ResolveNowOption) {}
diff --git a/vendor/google.golang.org/grpc/resolver/resolver.go b/vendor/google.golang.org/grpc/resolver/resolver.go
index 145cf477..e83da346 100644
--- a/vendor/google.golang.org/grpc/resolver/resolver.go
+++ b/vendor/google.golang.org/grpc/resolver/resolver.go
@@ -20,6 +20,10 @@
 // All APIs in this package are experimental.
 package resolver
 
+import (
+	"google.golang.org/grpc/serviceconfig"
+)
+
 var (
 	// m is a map from scheme to resolver builder.
 	m = make(map[string]Builder)
@@ -98,6 +102,16 @@ type BuildOption struct {
 	DisableServiceConfig bool
 }
 
+// State contains the current Resolver state relevant to the ClientConn.
+type State struct {
+	Addresses []Address // Resolved addresses for the target
+	// ServiceConfig is the parsed service config; obtained from
+	// serviceconfig.Parse.
+	ServiceConfig serviceconfig.Config
+
+	// TODO: add Err error
+}
+
 // ClientConn contains the callbacks for resolver to notify any updates
 // to the gRPC ClientConn.
 //
@@ -106,17 +120,38 @@ type BuildOption struct {
 // testing, the new implementation should embed this interface. This allows
 // gRPC to add new methods to this interface.
 type ClientConn interface {
+	// UpdateState updates the state of the ClientConn appropriately.
+	UpdateState(State)
 	// NewAddress is called by resolver to notify ClientConn a new list
 	// of resolved addresses.
 	// The address list should be the complete list of resolved addresses.
+	//
+	// Deprecated: Use UpdateState instead.
 	NewAddress(addresses []Address)
 	// NewServiceConfig is called by resolver to notify ClientConn a new
 	// service config. The service config should be provided as a json string.
+	//
+	// Deprecated: Use UpdateState instead.
 	NewServiceConfig(serviceConfig string)
 }
 
 // Target represents a target for gRPC, as specified in:
 // https://github.com/grpc/grpc/blob/master/doc/naming.md.
+// It is parsed from the target string that gets passed into Dial or DialContext by the user. And
+// grpc passes it to the resolver and the balancer.
+//
+// If the target follows the naming spec, and the parsed scheme is registered with grpc, we will
+// parse the target string according to the spec. e.g. "dns://some_authority/foo.bar" will be parsed
+// into &Target{Scheme: "dns", Authority: "some_authority", Endpoint: "foo.bar"}
+//
+// If the target does not contain a scheme, we will apply the default scheme, and set the Target to
+// be the full target string. e.g. "foo.bar" will be parsed into
+// &Target{Scheme: resolver.GetDefaultScheme(), Endpoint: "foo.bar"}.
+//
+// If the parsed scheme is not registered (i.e. no corresponding resolver available to resolve the
+// endpoint), we set the Scheme to be the default scheme, and set the Endpoint to be the full target
+// string. e.g. target string "unknown_scheme://authority/endpoint" will be parsed into
+// &Target{Scheme: resolver.GetDefaultScheme(), Endpoint: "unknown_scheme://authority/endpoint"}.
 type Target struct {
 	Scheme    string
 	Authority string
diff --git a/vendor/google.golang.org/grpc/resolver_conn_wrapper.go b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
index 494d6931..6934905b 100644
--- a/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
+++ b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
@@ -21,8 +21,10 @@ package grpc
 import (
 	"fmt"
 	"strings"
+	"sync/atomic"
 
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/resolver"
 )
 
@@ -33,11 +35,12 @@ type ccResolverWrapper struct {
 	resolver resolver.Resolver
 	addrCh   chan []resolver.Address
 	scCh     chan string
-	done     chan struct{}
+	done     uint32 // accessed atomically; set to 1 when closed.
+	curState resolver.State
 }
 
 // split2 returns the values from strings.SplitN(s, sep, 2).
-// If sep is not found, it returns ("", s, false) instead.
+// If sep is not found, it returns ("", "", false) instead.
 func split2(s, sep string) (string, string, bool) {
 	spl := strings.SplitN(s, sep, 2)
 	if len(spl) < 2 {
@@ -80,7 +83,6 @@ func newCCResolverWrapper(cc *ClientConn) (*ccResolverWrapper, error) {
 		cc:     cc,
 		addrCh: make(chan []resolver.Address, 1),
 		scCh:   make(chan string, 1),
-		done:   make(chan struct{}),
 	}
 
 	var err error
@@ -91,68 +93,76 @@ func newCCResolverWrapper(cc *ClientConn) (*ccResolverWrapper, error) {
 	return ccr, nil
 }
 
-func (ccr *ccResolverWrapper) start() {
-	go ccr.watcher()
-}
-
-// watcher processes address updates and service config updates sequentially.
-// Otherwise, we need to resolve possible races between address and service
-// config (e.g. they specify different balancer types).
-func (ccr *ccResolverWrapper) watcher() {
-	for {
-		select {
-		case <-ccr.done:
-			return
-		default:
-		}
-
-		select {
-		case addrs := <-ccr.addrCh:
-			select {
-			case <-ccr.done:
-				return
-			default:
-			}
-			grpclog.Infof("ccResolverWrapper: sending new addresses to cc: %v", addrs)
-			ccr.cc.handleResolvedAddrs(addrs, nil)
-		case sc := <-ccr.scCh:
-			select {
-			case <-ccr.done:
-				return
-			default:
-			}
-			grpclog.Infof("ccResolverWrapper: got new service config: %v", sc)
-			ccr.cc.handleServiceConfig(sc)
-		case <-ccr.done:
-			return
-		}
-	}
-}
-
 func (ccr *ccResolverWrapper) resolveNow(o resolver.ResolveNowOption) {
 	ccr.resolver.ResolveNow(o)
 }
 
 func (ccr *ccResolverWrapper) close() {
 	ccr.resolver.Close()
-	close(ccr.done)
+	atomic.StoreUint32(&ccr.done, 1)
 }
 
-// NewAddress is called by the resolver implemenetion to send addresses to gRPC.
+func (ccr *ccResolverWrapper) isDone() bool {
+	return atomic.LoadUint32(&ccr.done) == 1
+}
+
+func (ccr *ccResolverWrapper) UpdateState(s resolver.State) {
+	if ccr.isDone() {
+		return
+	}
+	grpclog.Infof("ccResolverWrapper: sending update to cc: %v", s)
+	if channelz.IsOn() {
+		ccr.addChannelzTraceEvent(s)
+	}
+	ccr.cc.updateResolverState(s)
+	ccr.curState = s
+}
+
+// NewAddress is called by the resolver implementation to send addresses to gRPC.
 func (ccr *ccResolverWrapper) NewAddress(addrs []resolver.Address) {
-	select {
-	case <-ccr.addrCh:
-	default:
+	if ccr.isDone() {
+		return
+	}
+	grpclog.Infof("ccResolverWrapper: sending new addresses to cc: %v", addrs)
+	if channelz.IsOn() {
+		ccr.addChannelzTraceEvent(resolver.State{Addresses: addrs, ServiceConfig: ccr.curState.ServiceConfig})
 	}
-	ccr.addrCh <- addrs
+	ccr.curState.Addresses = addrs
+	ccr.cc.updateResolverState(ccr.curState)
 }
 
-// NewServiceConfig is called by the resolver implemenetion to send service
+// NewServiceConfig is called by the resolver implementation to send service
 // configs to gRPC.
 func (ccr *ccResolverWrapper) NewServiceConfig(sc string) {
-	select {
-	case <-ccr.scCh:
-	default:
+	if ccr.isDone() {
+		return
+	}
+	grpclog.Infof("ccResolverWrapper: got new service config: %v", sc)
+	c, err := parseServiceConfig(sc)
+	if err != nil {
+		return
+	}
+	if channelz.IsOn() {
+		ccr.addChannelzTraceEvent(resolver.State{Addresses: ccr.curState.Addresses, ServiceConfig: c})
+	}
+	ccr.curState.ServiceConfig = c
+	ccr.cc.updateResolverState(ccr.curState)
+}
+
+func (ccr *ccResolverWrapper) addChannelzTraceEvent(s resolver.State) {
+	var updates []string
+	oldSC, oldOK := ccr.curState.ServiceConfig.(*ServiceConfig)
+	newSC, newOK := s.ServiceConfig.(*ServiceConfig)
+	if oldOK != newOK || (oldOK && newOK && oldSC.rawJSONString != newSC.rawJSONString) {
+		updates = append(updates, "service config updated")
+	}
+	if len(ccr.curState.Addresses) > 0 && len(s.Addresses) == 0 {
+		updates = append(updates, "resolver returned an empty address list")
+	} else if len(ccr.curState.Addresses) == 0 && len(s.Addresses) > 0 {
+		updates = append(updates, "resolver returned new addresses")
 	}
-	ccr.scCh <- sc
+	channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{
+		Desc:     fmt.Sprintf("Resolver state updated: %+v (%v)", s, strings.Join(updates, "; ")),
+		Severity: channelz.CtINFO,
+	})
 }
diff --git a/vendor/google.golang.org/grpc/rpc_util.go b/vendor/google.golang.org/grpc/rpc_util.go
index 61342c9c..088c3f1b 100644
--- a/vendor/google.golang.org/grpc/rpc_util.go
+++ b/vendor/google.golang.org/grpc/rpc_util.go
@@ -21,6 +21,7 @@ package grpc
 import (
 	"bytes"
 	"compress/gzip"
+	"context"
 	"encoding/binary"
 	"fmt"
 	"io"
@@ -31,7 +32,6 @@ import (
 	"sync"
 	"time"
 
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/encoding"
@@ -155,14 +155,12 @@ func (d *gzipDecompressor) Type() string {
 type callInfo struct {
 	compressorType        string
 	failFast              bool
-	stream                *clientStream
-	traceInfo             traceInfo // in trace.go
+	stream                ClientStream
 	maxReceiveMessageSize *int
 	maxSendMessageSize    *int
 	creds                 credentials.PerRPCCredentials
 	contentSubtype        string
 	codec                 baseCodec
-	disableRetry          bool
 	maxRetryRPCBufferSize int
 }
 
@@ -255,8 +253,8 @@ func (o PeerCallOption) after(c *callInfo) {
 	}
 }
 
-// FailFast configures the action to take when an RPC is attempted on broken
-// connections or unreachable servers.  If failFast is true, the RPC will fail
+// WaitForReady configures the action to take when an RPC is attempted on broken
+// connections or unreachable servers. If waitForReady is false, the RPC will fail
 // immediately. Otherwise, the RPC client will block the call until a
 // connection is available (or the call is canceled or times out) and will
 // retry the call if it fails due to a transient error.  gRPC will not retry if
@@ -264,7 +262,14 @@ func (o PeerCallOption) after(c *callInfo) {
 // the data.  Please refer to
 // https://github.com/grpc/grpc/blob/master/doc/wait-for-ready.md.
 //
-// By default, RPCs are "Fail Fast".
+// By default, RPCs don't "wait for ready".
+func WaitForReady(waitForReady bool) CallOption {
+	return FailFastCallOption{FailFast: !waitForReady}
+}
+
+// FailFast is the opposite of WaitForReady.
+//
+// Deprecated: use WaitForReady.
 func FailFast(failFast bool) CallOption {
 	return FailFastCallOption{FailFast: failFast}
 }
@@ -365,13 +370,13 @@ func (o CompressorCallOption) after(c *callInfo) {}
 // https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for
 // more details.
 //
-// If CallCustomCodec is not also used, the content-subtype will be used to
-// look up the Codec to use in the registry controlled by RegisterCodec. See
-// the documentation on RegisterCodec for details on registration. The lookup
-// of content-subtype is case-insensitive. If no such Codec is found, the call
+// If ForceCodec is not also used, the content-subtype will be used to look up
+// the Codec to use in the registry controlled by RegisterCodec. See the
+// documentation on RegisterCodec for details on registration. The lookup of
+// content-subtype is case-insensitive. If no such Codec is found, the call
 // will result in an error with code codes.Internal.
 //
-// If CallCustomCodec is also used, that Codec will be used for all request and
+// If ForceCodec is also used, that Codec will be used for all request and
 // response messages, with the content-subtype set to the given contentSubtype
 // here for requests.
 func CallContentSubtype(contentSubtype string) CallOption {
@@ -391,7 +396,7 @@ func (o ContentSubtypeCallOption) before(c *callInfo) error {
 }
 func (o ContentSubtypeCallOption) after(c *callInfo) {}
 
-// CallCustomCodec returns a CallOption that will set the given Codec to be
+// ForceCodec returns a CallOption that will set the given Codec to be
 // used for all request and response messages for a call. The result of calling
 // String() will be used as the content-subtype in a case-insensitive manner.
 //
@@ -403,12 +408,37 @@ func (o ContentSubtypeCallOption) after(c *callInfo) {}
 //
 // This function is provided for advanced users; prefer to use only
 // CallContentSubtype to select a registered codec instead.
+//
+// This is an EXPERIMENTAL API.
+func ForceCodec(codec encoding.Codec) CallOption {
+	return ForceCodecCallOption{Codec: codec}
+}
+
+// ForceCodecCallOption is a CallOption that indicates the codec used for
+// marshaling messages.
+//
+// This is an EXPERIMENTAL API.
+type ForceCodecCallOption struct {
+	Codec encoding.Codec
+}
+
+func (o ForceCodecCallOption) before(c *callInfo) error {
+	c.codec = o.Codec
+	return nil
+}
+func (o ForceCodecCallOption) after(c *callInfo) {}
+
+// CallCustomCodec behaves like ForceCodec, but accepts a grpc.Codec instead of
+// an encoding.Codec.
+//
+// Deprecated: use ForceCodec instead.
 func CallCustomCodec(codec Codec) CallOption {
 	return CustomCodecCallOption{Codec: codec}
 }
 
 // CustomCodecCallOption is a CallOption that indicates the codec used for
 // marshaling messages.
+//
 // This is an EXPERIMENTAL API.
 type CustomCodecCallOption struct {
 	Codec Codec
@@ -533,7 +563,10 @@ func compress(in []byte, cp Compressor, compressor encoding.Compressor) ([]byte,
 	}
 	cbuf := &bytes.Buffer{}
 	if compressor != nil {
-		z, _ := compressor.Compress(cbuf)
+		z, err := compressor.Compress(cbuf)
+		if err != nil {
+			return nil, wrapErr(err)
+		}
 		if _, err := z.Write(in); err != nil {
 			return nil, wrapErr(err)
 		}
@@ -597,20 +630,22 @@ func checkRecvPayload(pf payloadFormat, recvCompress string, haveCompressor bool
 	return nil
 }
 
-// For the two compressor parameters, both should not be set, but if they are,
-// dc takes precedence over compressor.
-// TODO(dfawley): wrap the old compressor/decompressor using the new API?
-func recv(p *parser, c baseCodec, s *transport.Stream, dc Decompressor, m interface{}, maxReceiveMessageSize int, inPayload *stats.InPayload, compressor encoding.Compressor) error {
+type payloadInfo struct {
+	wireLength        int // The compressed length got from wire.
+	uncompressedBytes []byte
+}
+
+func recvAndDecompress(p *parser, s *transport.Stream, dc Decompressor, maxReceiveMessageSize int, payInfo *payloadInfo, compressor encoding.Compressor) ([]byte, error) {
 	pf, d, err := p.recvMsg(maxReceiveMessageSize)
 	if err != nil {
-		return err
+		return nil, err
 	}
-	if inPayload != nil {
-		inPayload.WireLength = len(d)
+	if payInfo != nil {
+		payInfo.wireLength = len(d)
 	}
 
 	if st := checkRecvPayload(pf, s.RecvCompress(), compressor != nil || dc != nil); st != nil {
-		return st.Err()
+		return nil, st.Err()
 	}
 
 	if pf == compressionMade {
@@ -619,45 +654,74 @@ func recv(p *parser, c baseCodec, s *transport.Stream, dc Decompressor, m interf
 		if dc != nil {
 			d, err = dc.Do(bytes.NewReader(d))
 			if err != nil {
-				return status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err)
+				return nil, status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err)
 			}
 		} else {
 			dcReader, err := compressor.Decompress(bytes.NewReader(d))
 			if err != nil {
-				return status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err)
+				return nil, status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err)
 			}
-			d, err = ioutil.ReadAll(dcReader)
+			// Read from LimitReader with limit max+1. So if the underlying
+			// reader is over limit, the result will be bigger than max.
+			d, err = ioutil.ReadAll(io.LimitReader(dcReader, int64(maxReceiveMessageSize)+1))
 			if err != nil {
-				return status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err)
+				return nil, status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err)
 			}
 		}
 	}
 	if len(d) > maxReceiveMessageSize {
 		// TODO: Revisit the error code. Currently keep it consistent with java
 		// implementation.
-		return status.Errorf(codes.ResourceExhausted, "grpc: received message larger than max (%d vs. %d)", len(d), maxReceiveMessageSize)
+		return nil, status.Errorf(codes.ResourceExhausted, "grpc: received message larger than max (%d vs. %d)", len(d), maxReceiveMessageSize)
+	}
+	return d, nil
+}
+
+// For the two compressor parameters, both should not be set, but if they are,
+// dc takes precedence over compressor.
+// TODO(dfawley): wrap the old compressor/decompressor using the new API?
+func recv(p *parser, c baseCodec, s *transport.Stream, dc Decompressor, m interface{}, maxReceiveMessageSize int, payInfo *payloadInfo, compressor encoding.Compressor) error {
+	d, err := recvAndDecompress(p, s, dc, maxReceiveMessageSize, payInfo, compressor)
+	if err != nil {
+		return err
 	}
 	if err := c.Unmarshal(d, m); err != nil {
 		return status.Errorf(codes.Internal, "grpc: failed to unmarshal the received message %v", err)
 	}
-	if inPayload != nil {
-		inPayload.RecvTime = time.Now()
-		inPayload.Payload = m
-		// TODO truncate large payload.
-		inPayload.Data = d
-		inPayload.Length = len(d)
+	if payInfo != nil {
+		payInfo.uncompressedBytes = d
 	}
 	return nil
 }
 
+// Information about RPC
 type rpcInfo struct {
-	failfast bool
+	failfast      bool
+	preloaderInfo *compressorInfo
+}
+
+// Information about Preloader
+// Responsible for storing codec, and compressors
+// If stream (s) has  context s.Context which stores rpcInfo that has non nil
+// pointers to codec, and compressors, then we can use preparedMsg for Async message prep
+// and reuse marshalled bytes
+type compressorInfo struct {
+	codec baseCodec
+	cp    Compressor
+	comp  encoding.Compressor
 }
 
 type rpcInfoContextKey struct{}
 
-func newContextWithRPCInfo(ctx context.Context, failfast bool) context.Context {
-	return context.WithValue(ctx, rpcInfoContextKey{}, &rpcInfo{failfast: failfast})
+func newContextWithRPCInfo(ctx context.Context, failfast bool, codec baseCodec, cp Compressor, comp encoding.Compressor) context.Context {
+	return context.WithValue(ctx, rpcInfoContextKey{}, &rpcInfo{
+		failfast: failfast,
+		preloaderInfo: &compressorInfo{
+			codec: codec,
+			cp:    cp,
+			comp:  comp,
+		},
+	})
 }
 
 func rpcInfoFromContext(ctx context.Context) (s *rpcInfo, ok bool) {
@@ -668,23 +732,17 @@ func rpcInfoFromContext(ctx context.Context) (s *rpcInfo, ok bool) {
 // Code returns the error code for err if it was produced by the rpc system.
 // Otherwise, it returns codes.Unknown.
 //
-// Deprecated: use status.FromError and Code method instead.
+// Deprecated: use status.Code instead.
 func Code(err error) codes.Code {
-	if s, ok := status.FromError(err); ok {
-		return s.Code()
-	}
-	return codes.Unknown
+	return status.Code(err)
 }
 
 // ErrorDesc returns the error description of err if it was produced by the rpc system.
 // Otherwise, it returns err.Error() or empty string when err is nil.
 //
-// Deprecated: use status.FromError and Message method instead.
+// Deprecated: use status.Convert and Message method instead.
 func ErrorDesc(err error) string {
-	if s, ok := status.FromError(err); ok {
-		return s.Message()
-	}
-	return err.Error()
+	return status.Convert(err).Message()
 }
 
 // Errorf returns an error containing an error code and a description;
@@ -695,6 +753,31 @@ func Errorf(c codes.Code, format string, a ...interface{}) error {
 	return status.Errorf(c, format, a...)
 }
 
+// toRPCErr converts an error into an error from the status package.
+func toRPCErr(err error) error {
+	if err == nil || err == io.EOF {
+		return err
+	}
+	if err == io.ErrUnexpectedEOF {
+		return status.Error(codes.Internal, err.Error())
+	}
+	if _, ok := status.FromError(err); ok {
+		return err
+	}
+	switch e := err.(type) {
+	case transport.ConnectionError:
+		return status.Error(codes.Unavailable, e.Desc)
+	default:
+		switch err {
+		case context.DeadlineExceeded:
+			return status.Error(codes.DeadlineExceeded, err.Error())
+		case context.Canceled:
+			return status.Error(codes.Canceled, err.Error())
+		}
+	}
+	return status.Error(codes.Unknown, err.Error())
+}
+
 // setCallInfoCodec should only be called after CallOptions have been applied.
 func setCallInfoCodec(c *callInfo) error {
 	if c.codec != nil {
@@ -750,6 +833,19 @@ func parseDialTarget(target string) (net string, addr string) {
 	return net, target
 }
 
+// channelzData is used to store channelz related data for ClientConn, addrConn and Server.
+// These fields cannot be embedded in the original structs (e.g. ClientConn), since to do atomic
+// operation on int64 variable on 32-bit machine, user is responsible to enforce memory alignment.
+// Here, by grouping those int64 fields inside a struct, we are enforcing the alignment.
+type channelzData struct {
+	callsStarted   int64
+	callsFailed    int64
+	callsSucceeded int64
+	// lastCallStartedTime stores the timestamp that last call starts. It is of int64 type instead of
+	// time.Time since it's more costly to atomically update time.Time variable than int64 variable.
+	lastCallStartedTime int64
+}
+
 // The SupportPackageIsVersion variables are referenced from generated protocol
 // buffer files to ensure compatibility with the gRPC version used.  The latest
 // support package version is 5.
diff --git a/vendor/google.golang.org/grpc/server.go b/vendor/google.golang.org/grpc/server.go
index f5bea723..f064b73e 100644
--- a/vendor/google.golang.org/grpc/server.go
+++ b/vendor/google.golang.org/grpc/server.go
@@ -19,7 +19,7 @@
 package grpc
 
 import (
-	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -30,12 +30,9 @@ import (
 	"runtime"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
-	"io/ioutil"
-
-	"golang.org/x/net/context"
-	"golang.org/x/net/http2"
 	"golang.org/x/net/trace"
 
 	"google.golang.org/grpc/codes"
@@ -43,11 +40,13 @@ import (
 	"google.golang.org/grpc/encoding"
 	"google.golang.org/grpc/encoding/proto"
 	"google.golang.org/grpc/grpclog"
-	"google.golang.org/grpc/internal"
+	"google.golang.org/grpc/internal/binarylog"
 	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/internal/grpcsync"
 	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/tap"
@@ -58,6 +57,8 @@ const (
 	defaultServerMaxSendMessageSize    = math.MaxInt32
 )
 
+var statusOK = status.New(codes.OK, "")
+
 type methodHandler func(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor UnaryServerInterceptor) (interface{}, error)
 
 // MethodDesc represents an RPC service's method specification.
@@ -88,33 +89,27 @@ type service struct {
 
 // Server is a gRPC server to serve RPC requests.
 type Server struct {
-	opts options
+	opts serverOptions
 
 	mu     sync.Mutex // guards following
 	lis    map[net.Listener]bool
-	conns  map[io.Closer]bool
+	conns  map[transport.ServerTransport]bool
 	serve  bool
 	drain  bool
 	cv     *sync.Cond          // signaled when connections close for GracefulStop
 	m      map[string]*service // service name -> service info
 	events trace.EventLog
 
-	quit               chan struct{}
-	done               chan struct{}
-	quitOnce           sync.Once
-	doneOnce           sync.Once
+	quit               *grpcsync.Event
+	done               *grpcsync.Event
 	channelzRemoveOnce sync.Once
 	serveWG            sync.WaitGroup // counts active Serve goroutines for GracefulStop
 
-	channelzID          int64 // channelz unique identification number
-	czmu                sync.RWMutex
-	callsStarted        int64
-	callsFailed         int64
-	callsSucceeded      int64
-	lastCallStartedTime time.Time
+	channelzID int64 // channelz unique identification number
+	czData     *channelzData
 }
 
-type options struct {
+type serverOptions struct {
 	creds                 credentials.TransportCredentials
 	codec                 baseCodec
 	cp                    Compressor
@@ -126,7 +121,6 @@ type options struct {
 	maxConcurrentStreams  uint32
 	maxReceiveMessageSize int
 	maxSendMessageSize    int
-	useHandlerImpl        bool // use http.Handler-based server
 	unknownStreamDesc     *StreamDesc
 	keepaliveParams       keepalive.ServerParameters
 	keepalivePolicy       keepalive.EnforcementPolicy
@@ -138,7 +132,7 @@ type options struct {
 	maxHeaderListSize     *uint32
 }
 
-var defaultServerOptions = options{
+var defaultServerOptions = serverOptions{
 	maxReceiveMessageSize: defaultServerMaxReceiveMessageSize,
 	maxSendMessageSize:    defaultServerMaxSendMessageSize,
 	connectionTimeout:     120 * time.Second,
@@ -147,7 +141,33 @@ var defaultServerOptions = options{
 }
 
 // A ServerOption sets options such as credentials, codec and keepalive parameters, etc.
-type ServerOption func(*options)
+type ServerOption interface {
+	apply(*serverOptions)
+}
+
+// EmptyServerOption does not alter the server configuration. It can be embedded
+// in another structure to build custom server options.
+//
+// This API is EXPERIMENTAL.
+type EmptyServerOption struct{}
+
+func (EmptyServerOption) apply(*serverOptions) {}
+
+// funcServerOption wraps a function that modifies serverOptions into an
+// implementation of the ServerOption interface.
+type funcServerOption struct {
+	f func(*serverOptions)
+}
+
+func (fdo *funcServerOption) apply(do *serverOptions) {
+	fdo.f(do)
+}
+
+func newFuncServerOption(f func(*serverOptions)) *funcServerOption {
+	return &funcServerOption{
+		f: f,
+	}
+}
 
 // WriteBufferSize determines how much data can be batched before doing a write on the wire.
 // The corresponding memory allocation for this buffer will be twice the size to keep syscalls low.
@@ -155,9 +175,9 @@ type ServerOption func(*options)
 // Zero will disable the write buffer such that each write will be on underlying connection.
 // Note: A Send call may not directly translate to a write.
 func WriteBufferSize(s int) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.writeBufferSize = s
-	}
+	})
 }
 
 // ReadBufferSize lets you set the size of read buffer, this determines how much data can be read at most
@@ -166,48 +186,53 @@ func WriteBufferSize(s int) ServerOption {
 // Zero will disable read buffer for a connection so data framer can access the underlying
 // conn directly.
 func ReadBufferSize(s int) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.readBufferSize = s
-	}
+	})
 }
 
 // InitialWindowSize returns a ServerOption that sets window size for stream.
 // The lower bound for window size is 64K and any value smaller than that will be ignored.
 func InitialWindowSize(s int32) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.initialWindowSize = s
-	}
+	})
 }
 
 // InitialConnWindowSize returns a ServerOption that sets window size for a connection.
 // The lower bound for window size is 64K and any value smaller than that will be ignored.
 func InitialConnWindowSize(s int32) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.initialConnWindowSize = s
-	}
+	})
 }
 
 // KeepaliveParams returns a ServerOption that sets keepalive and max-age parameters for the server.
 func KeepaliveParams(kp keepalive.ServerParameters) ServerOption {
-	return func(o *options) {
-		o.keepaliveParams = kp
+	if kp.Time > 0 && kp.Time < time.Second {
+		grpclog.Warning("Adjusting keepalive ping interval to minimum period of 1s")
+		kp.Time = time.Second
 	}
+
+	return newFuncServerOption(func(o *serverOptions) {
+		o.keepaliveParams = kp
+	})
 }
 
 // KeepaliveEnforcementPolicy returns a ServerOption that sets keepalive enforcement policy for the server.
 func KeepaliveEnforcementPolicy(kep keepalive.EnforcementPolicy) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.keepalivePolicy = kep
-	}
+	})
 }
 
 // CustomCodec returns a ServerOption that sets a codec for message marshaling and unmarshaling.
 //
 // This will override any lookups by content-subtype for Codecs registered with RegisterCodec.
 func CustomCodec(codec Codec) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.codec = codec
-	}
+	})
 }
 
 // RPCCompressor returns a ServerOption that sets a compressor for outbound
@@ -218,9 +243,9 @@ func CustomCodec(codec Codec) ServerOption {
 //
 // Deprecated: use encoding.RegisterCompressor instead.
 func RPCCompressor(cp Compressor) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.cp = cp
-	}
+	})
 }
 
 // RPCDecompressor returns a ServerOption that sets a decompressor for inbound
@@ -229,9 +254,9 @@ func RPCCompressor(cp Compressor) ServerOption {
 //
 // Deprecated: use encoding.RegisterCompressor instead.
 func RPCDecompressor(dc Decompressor) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.dc = dc
-	}
+	})
 }
 
 // MaxMsgSize returns a ServerOption to set the max message size in bytes the server can receive.
@@ -245,73 +270,73 @@ func MaxMsgSize(m int) ServerOption {
 // MaxRecvMsgSize returns a ServerOption to set the max message size in bytes the server can receive.
 // If this is not set, gRPC uses the default 4MB.
 func MaxRecvMsgSize(m int) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.maxReceiveMessageSize = m
-	}
+	})
 }
 
 // MaxSendMsgSize returns a ServerOption to set the max message size in bytes the server can send.
-// If this is not set, gRPC uses the default 4MB.
+// If this is not set, gRPC uses the default `math.MaxInt32`.
 func MaxSendMsgSize(m int) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.maxSendMessageSize = m
-	}
+	})
 }
 
 // MaxConcurrentStreams returns a ServerOption that will apply a limit on the number
 // of concurrent streams to each ServerTransport.
 func MaxConcurrentStreams(n uint32) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.maxConcurrentStreams = n
-	}
+	})
 }
 
 // Creds returns a ServerOption that sets credentials for server connections.
 func Creds(c credentials.TransportCredentials) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.creds = c
-	}
+	})
 }
 
 // UnaryInterceptor returns a ServerOption that sets the UnaryServerInterceptor for the
 // server. Only one unary interceptor can be installed. The construction of multiple
 // interceptors (e.g., chaining) can be implemented at the caller.
 func UnaryInterceptor(i UnaryServerInterceptor) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		if o.unaryInt != nil {
 			panic("The unary server interceptor was already set and may not be reset.")
 		}
 		o.unaryInt = i
-	}
+	})
 }
 
 // StreamInterceptor returns a ServerOption that sets the StreamServerInterceptor for the
 // server. Only one stream interceptor can be installed.
 func StreamInterceptor(i StreamServerInterceptor) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		if o.streamInt != nil {
 			panic("The stream server interceptor was already set and may not be reset.")
 		}
 		o.streamInt = i
-	}
+	})
 }
 
 // InTapHandle returns a ServerOption that sets the tap handle for all the server
 // transport to be created. Only one can be installed.
 func InTapHandle(h tap.ServerInHandle) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		if o.inTapHandle != nil {
 			panic("The tap handle was already set and may not be reset.")
 		}
 		o.inTapHandle = h
-	}
+	})
 }
 
 // StatsHandler returns a ServerOption that sets the stats handler for the server.
 func StatsHandler(h stats.Handler) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.statsHandler = h
-	}
+	})
 }
 
 // UnknownServiceHandler returns a ServerOption that allows for adding a custom
@@ -321,7 +346,7 @@ func StatsHandler(h stats.Handler) ServerOption {
 // The handling function has full access to the Context of the request and the
 // stream, and the invocation bypasses interceptors.
 func UnknownServiceHandler(streamHandler StreamHandler) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.unknownStreamDesc = &StreamDesc{
 			StreamName: "unknown_service_handler",
 			Handler:    streamHandler,
@@ -329,7 +354,7 @@ func UnknownServiceHandler(streamHandler StreamHandler) ServerOption {
 			ClientStreams: true,
 			ServerStreams: true,
 		}
-	}
+	})
 }
 
 // ConnectionTimeout returns a ServerOption that sets the timeout for
@@ -339,17 +364,17 @@ func UnknownServiceHandler(streamHandler StreamHandler) ServerOption {
 //
 // This API is EXPERIMENTAL.
 func ConnectionTimeout(d time.Duration) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.connectionTimeout = d
-	}
+	})
 }
 
 // MaxHeaderListSize returns a ServerOption that sets the max (uncompressed) size
 // of header list that the server is prepared to accept.
 func MaxHeaderListSize(s uint32) ServerOption {
-	return func(o *options) {
+	return newFuncServerOption(func(o *serverOptions) {
 		o.maxHeaderListSize = &s
-	}
+	})
 }
 
 // NewServer creates a gRPC server which has no service registered and has not
@@ -357,15 +382,16 @@ func MaxHeaderListSize(s uint32) ServerOption {
 func NewServer(opt ...ServerOption) *Server {
 	opts := defaultServerOptions
 	for _, o := range opt {
-		o(&opts)
+		o.apply(&opts)
 	}
 	s := &Server{
-		lis:   make(map[net.Listener]bool),
-		opts:  opts,
-		conns: make(map[io.Closer]bool),
-		m:     make(map[string]*service),
-		quit:  make(chan struct{}),
-		done:  make(chan struct{}),
+		lis:    make(map[net.Listener]bool),
+		opts:   opts,
+		conns:  make(map[transport.ServerTransport]bool),
+		m:      make(map[string]*service),
+		quit:   grpcsync.NewEvent(),
+		done:   grpcsync.NewEvent(),
+		czData: new(channelzData),
 	}
 	s.cv = sync.NewCond(&s.mu)
 	if EnableTracing {
@@ -374,7 +400,7 @@ func NewServer(opt ...ServerOption) *Server {
 	}
 
 	if channelz.IsOn() {
-		s.channelzID = channelz.RegisterServer(s, "")
+		s.channelzID = channelz.RegisterServer(&channelzServer{s}, "")
 	}
 	return s
 }
@@ -531,11 +557,9 @@ func (s *Server) Serve(lis net.Listener) error {
 	s.serveWG.Add(1)
 	defer func() {
 		s.serveWG.Done()
-		select {
-		// Stop or GracefulStop called; block until done and return nil.
-		case <-s.quit:
-			<-s.done
-		default:
+		if s.quit.HasFired() {
+			// Stop or GracefulStop called; block until done and return nil.
+			<-s.done.Done()
 		}
 	}()
 
@@ -543,7 +567,7 @@ func (s *Server) Serve(lis net.Listener) error {
 	s.lis[ls] = true
 
 	if channelz.IsOn() {
-		ls.channelzID = channelz.RegisterListenSocket(ls, s.channelzID, "")
+		ls.channelzID = channelz.RegisterListenSocket(ls, s.channelzID, lis.Addr().String())
 	}
 	s.mu.Unlock()
 
@@ -578,7 +602,7 @@ func (s *Server) Serve(lis net.Listener) error {
 				timer := time.NewTimer(tempDelay)
 				select {
 				case <-timer.C:
-				case <-s.quit:
+				case <-s.quit.Done():
 					timer.Stop()
 					return nil
 				}
@@ -588,10 +612,8 @@ func (s *Server) Serve(lis net.Listener) error {
 			s.printf("done serving; Accept = %v", err)
 			s.mu.Unlock()
 
-			select {
-			case <-s.quit:
+			if s.quit.HasFired() {
 				return nil
-			default:
 			}
 			return err
 		}
@@ -612,50 +634,39 @@ func (s *Server) Serve(lis net.Listener) error {
 // handleRawConn forks a goroutine to handle a just-accepted connection that
 // has not had any I/O performed on it yet.
 func (s *Server) handleRawConn(rawConn net.Conn) {
+	if s.quit.HasFired() {
+		rawConn.Close()
+		return
+	}
 	rawConn.SetDeadline(time.Now().Add(s.opts.connectionTimeout))
 	conn, authInfo, err := s.useTransportAuthenticator(rawConn)
 	if err != nil {
-		s.mu.Lock()
-		s.errorf("ServerHandshake(%q) failed: %v", rawConn.RemoteAddr(), err)
-		s.mu.Unlock()
-		grpclog.Warningf("grpc: Server.Serve failed to complete security handshake from %q: %v", rawConn.RemoteAddr(), err)
-		// If serverHandshake returns ErrConnDispatched, keep rawConn open.
+		// ErrConnDispatched means that the connection was dispatched away from
+		// gRPC; those connections should be left open.
 		if err != credentials.ErrConnDispatched {
+			s.mu.Lock()
+			s.errorf("ServerHandshake(%q) failed: %v", rawConn.RemoteAddr(), err)
+			s.mu.Unlock()
+			grpclog.Warningf("grpc: Server.Serve failed to complete security handshake from %q: %v", rawConn.RemoteAddr(), err)
 			rawConn.Close()
 		}
 		rawConn.SetDeadline(time.Time{})
 		return
 	}
 
-	s.mu.Lock()
-	if s.conns == nil {
-		s.mu.Unlock()
-		conn.Close()
+	// Finish handshaking (HTTP2)
+	st := s.newHTTP2Transport(conn, authInfo)
+	if st == nil {
 		return
 	}
-	s.mu.Unlock()
-
-	var serve func()
-	c := conn.(io.Closer)
-	if s.opts.useHandlerImpl {
-		serve = func() { s.serveUsingHandler(conn) }
-	} else {
-		// Finish handshaking (HTTP2)
-		st := s.newHTTP2Transport(conn, authInfo)
-		if st == nil {
-			return
-		}
-		c = st
-		serve = func() { s.serveStreams(st) }
-	}
 
 	rawConn.SetDeadline(time.Time{})
-	if !s.addConn(c) {
+	if !s.addConn(st) {
 		return
 	}
 	go func() {
-		serve()
-		s.removeConn(c)
+		s.serveStreams(st)
+		s.removeConn(st)
 	}()
 }
 
@@ -710,27 +721,6 @@ func (s *Server) serveStreams(st transport.ServerTransport) {
 
 var _ http.Handler = (*Server)(nil)
 
-// serveUsingHandler is called from handleRawConn when s is configured
-// to handle requests via the http.Handler interface. It sets up a
-// net/http.Server to handle the just-accepted conn. The http.Server
-// is configured to route all incoming requests (all HTTP/2 streams)
-// to ServeHTTP, which creates a new ServerTransport for each stream.
-// serveUsingHandler blocks until conn closes.
-//
-// This codepath is only used when Server.TestingUseHandlerImpl has
-// been configured. This lets the end2end tests exercise the ServeHTTP
-// method as one of the environment types.
-//
-// conn is the *tls.Conn that's already been authenticated.
-func (s *Server) serveUsingHandler(conn net.Conn) {
-	h2s := &http2.Server{
-		MaxConcurrentStreams: s.opts.maxConcurrentStreams,
-	}
-	h2s.ServeConn(conn, &http2.ServeConnOpts{
-		Handler: s,
-	})
-}
-
 // ServeHTTP implements the Go standard library's http.Handler
 // interface by responding to the gRPC request r, by looking up
 // the requested gRPC method in the gRPC server s.
@@ -771,6 +761,9 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 // traceInfo returns a traceInfo and associates it with stream, if tracing is enabled.
 // If tracing is not enabled, it returns nil.
 func (s *Server) traceInfo(st transport.ServerTransport, stream *transport.Stream) (trInfo *traceInfo) {
+	if !EnableTracing {
+		return nil
+	}
 	tr, ok := trace.FromContext(stream.Context())
 	if !ok {
 		return nil
@@ -778,71 +771,62 @@ func (s *Server) traceInfo(st transport.ServerTransport, stream *transport.Strea
 
 	trInfo = &traceInfo{
 		tr: tr,
+		firstLine: firstLine{
+			client:     false,
+			remoteAddr: st.RemoteAddr(),
+		},
 	}
-	trInfo.firstLine.client = false
-	trInfo.firstLine.remoteAddr = st.RemoteAddr()
-
 	if dl, ok := stream.Context().Deadline(); ok {
-		trInfo.firstLine.deadline = dl.Sub(time.Now())
+		trInfo.firstLine.deadline = time.Until(dl)
 	}
 	return trInfo
 }
 
-func (s *Server) addConn(c io.Closer) bool {
+func (s *Server) addConn(st transport.ServerTransport) bool {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 	if s.conns == nil {
-		c.Close()
+		st.Close()
 		return false
 	}
 	if s.drain {
 		// Transport added after we drained our existing conns: drain it
 		// immediately.
-		c.(transport.ServerTransport).Drain()
+		st.Drain()
 	}
-	s.conns[c] = true
+	s.conns[st] = true
 	return true
 }
 
-func (s *Server) removeConn(c io.Closer) {
+func (s *Server) removeConn(st transport.ServerTransport) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 	if s.conns != nil {
-		delete(s.conns, c)
+		delete(s.conns, st)
 		s.cv.Broadcast()
 	}
 }
 
-// ChannelzMetric returns ServerInternalMetric of current server.
-// This is an EXPERIMENTAL API.
-func (s *Server) ChannelzMetric() *channelz.ServerInternalMetric {
-	s.czmu.RLock()
-	defer s.czmu.RUnlock()
+func (s *Server) channelzMetric() *channelz.ServerInternalMetric {
 	return &channelz.ServerInternalMetric{
-		CallsStarted:             s.callsStarted,
-		CallsSucceeded:           s.callsSucceeded,
-		CallsFailed:              s.callsFailed,
-		LastCallStartedTimestamp: s.lastCallStartedTime,
+		CallsStarted:             atomic.LoadInt64(&s.czData.callsStarted),
+		CallsSucceeded:           atomic.LoadInt64(&s.czData.callsSucceeded),
+		CallsFailed:              atomic.LoadInt64(&s.czData.callsFailed),
+		LastCallStartedTimestamp: time.Unix(0, atomic.LoadInt64(&s.czData.lastCallStartedTime)),
 	}
 }
 
 func (s *Server) incrCallsStarted() {
-	s.czmu.Lock()
-	s.callsStarted++
-	s.lastCallStartedTime = time.Now()
-	s.czmu.Unlock()
+	atomic.AddInt64(&s.czData.callsStarted, 1)
+	atomic.StoreInt64(&s.czData.lastCallStartedTime, time.Now().UnixNano())
 }
 
 func (s *Server) incrCallsSucceeded() {
-	s.czmu.Lock()
-	s.callsSucceeded++
-	s.czmu.Unlock()
+	atomic.AddInt64(&s.czData.callsSucceeded, 1)
 }
 
 func (s *Server) incrCallsFailed() {
-	s.czmu.Lock()
-	s.callsFailed++
-	s.czmu.Unlock()
+	atomic.AddInt64(&s.czData.callsFailed, 1)
 }
 
 func (s *Server) sendResponse(t transport.ServerTransport, stream *transport.Stream, msg interface{}, cp Compressor, opts *transport.Options, comp encoding.Compressor) error {
@@ -899,7 +883,6 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 	}
 	if trInfo != nil {
 		defer trInfo.tr.Finish()
-		trInfo.firstLine.client = false
 		trInfo.tr.LazyLog(&trInfo.firstLine, false)
 		defer func() {
 			if err != nil && err != io.EOF {
@@ -909,6 +892,30 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		}()
 	}
 
+	binlog := binarylog.GetMethodLogger(stream.Method())
+	if binlog != nil {
+		ctx := stream.Context()
+		md, _ := metadata.FromIncomingContext(ctx)
+		logEntry := &binarylog.ClientHeader{
+			Header:     md,
+			MethodName: stream.Method(),
+			PeerAddr:   nil,
+		}
+		if deadline, ok := ctx.Deadline(); ok {
+			logEntry.Timeout = time.Until(deadline)
+			if logEntry.Timeout < 0 {
+				logEntry.Timeout = 0
+			}
+		}
+		if a := md[":authority"]; len(a) > 0 {
+			logEntry.Authority = a[0]
+		}
+		if peer, ok := peer.FromContext(ctx); ok {
+			logEntry.PeerAddr = peer.Addr
+		}
+		binlog.Log(logEntry)
+	}
+
 	// comp and cp are used for compression.  decomp and dc are used for
 	// decompression.  If comp and decomp are both set, they are the same;
 	// however they are kept separate to ensure that at most one of the
@@ -945,77 +952,39 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		}
 	}
 
-	p := &parser{r: stream}
-	pf, req, err := p.recvMsg(s.opts.maxReceiveMessageSize)
-	if err == io.EOF {
-		// The entire stream is done (for unary RPC only).
-		return err
-	}
-	if err == io.ErrUnexpectedEOF {
-		err = status.Errorf(codes.Internal, io.ErrUnexpectedEOF.Error())
+	var payInfo *payloadInfo
+	if sh != nil || binlog != nil {
+		payInfo = &payloadInfo{}
 	}
+	d, err := recvAndDecompress(&parser{r: stream}, stream, dc, s.opts.maxReceiveMessageSize, payInfo, decomp)
 	if err != nil {
 		if st, ok := status.FromError(err); ok {
 			if e := t.WriteStatus(stream, st); e != nil {
 				grpclog.Warningf("grpc: Server.processUnaryRPC failed to write status %v", e)
 			}
-		} else {
-			switch st := err.(type) {
-			case transport.ConnectionError:
-				// Nothing to do here.
-			default:
-				panic(fmt.Sprintf("grpc: Unexpected error (%T) from recvMsg: %v", st, st))
-			}
 		}
 		return err
 	}
 	if channelz.IsOn() {
 		t.IncrMsgRecv()
 	}
-	if st := checkRecvPayload(pf, stream.RecvCompress(), dc != nil || decomp != nil); st != nil {
-		if e := t.WriteStatus(stream, st); e != nil {
-			grpclog.Warningf("grpc: Server.processUnaryRPC failed to write status %v", e)
-		}
-		return st.Err()
-	}
-	var inPayload *stats.InPayload
-	if sh != nil {
-		inPayload = &stats.InPayload{
-			RecvTime: time.Now(),
-		}
-	}
 	df := func(v interface{}) error {
-		if inPayload != nil {
-			inPayload.WireLength = len(req)
-		}
-		if pf == compressionMade {
-			var err error
-			if dc != nil {
-				req, err = dc.Do(bytes.NewReader(req))
-				if err != nil {
-					return status.Errorf(codes.Internal, err.Error())
-				}
-			} else {
-				tmp, _ := decomp.Decompress(bytes.NewReader(req))
-				req, err = ioutil.ReadAll(tmp)
-				if err != nil {
-					return status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err)
-				}
-			}
-		}
-		if len(req) > s.opts.maxReceiveMessageSize {
-			// TODO: Revisit the error code. Currently keep it consistent with
-			// java implementation.
-			return status.Errorf(codes.ResourceExhausted, "grpc: received message larger than max (%d vs. %d)", len(req), s.opts.maxReceiveMessageSize)
-		}
-		if err := s.getCodec(stream.ContentSubtype()).Unmarshal(req, v); err != nil {
+		if err := s.getCodec(stream.ContentSubtype()).Unmarshal(d, v); err != nil {
 			return status.Errorf(codes.Internal, "grpc: error unmarshalling request: %v", err)
 		}
-		if inPayload != nil {
-			inPayload.Payload = v
-			inPayload.Data = req
-			inPayload.Length = len(req)
-			sh.HandleRPC(stream.Context(), inPayload)
+		if sh != nil {
+			sh.HandleRPC(stream.Context(), &stats.InPayload{
+				RecvTime:   time.Now(),
+				Payload:    v,
+				WireLength: payInfo.wireLength,
+				Data:       d,
+				Length:     len(d),
+			})
+		}
+		if binlog != nil {
+			binlog.Log(&binarylog.ClientMessage{
+				Message: d,
+			})
 		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&payload{sent: false, msg: v}, true)
@@ -1038,6 +1007,19 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		if e := t.WriteStatus(stream, appStatus); e != nil {
 			grpclog.Warningf("grpc: Server.processUnaryRPC failed to write status: %v", e)
 		}
+		if binlog != nil {
+			if h, _ := stream.Header(); h.Len() > 0 {
+				// Only log serverHeader if there was header. Otherwise it can
+				// be trailer only.
+				binlog.Log(&binarylog.ServerHeader{
+					Header: h,
+				})
+			}
+			binlog.Log(&binarylog.ServerTrailer{
+				Trailer: stream.Trailer(),
+				Err:     appErr,
+			})
+		}
 		return appErr
 	}
 	if trInfo != nil {
@@ -1062,8 +1044,27 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 				panic(fmt.Sprintf("grpc: Unexpected error (%T) from sendResponse: %v", st, st))
 			}
 		}
+		if binlog != nil {
+			h, _ := stream.Header()
+			binlog.Log(&binarylog.ServerHeader{
+				Header: h,
+			})
+			binlog.Log(&binarylog.ServerTrailer{
+				Trailer: stream.Trailer(),
+				Err:     appErr,
+			})
+		}
 		return err
 	}
+	if binlog != nil {
+		h, _ := stream.Header()
+		binlog.Log(&binarylog.ServerHeader{
+			Header: h,
+		})
+		binlog.Log(&binarylog.ServerMessage{
+			Message: reply,
+		})
+	}
 	if channelz.IsOn() {
 		t.IncrMsgSent()
 	}
@@ -1073,7 +1074,14 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 	// TODO: Should we be logging if writing status failed here, like above?
 	// Should the logging be in WriteStatus?  Should we ignore the WriteStatus
 	// error or allow the stats handler to see it?
-	return t.WriteStatus(stream, status.New(codes.OK, ""))
+	err = t.WriteStatus(stream, statusOK)
+	if binlog != nil {
+		binlog.Log(&binarylog.ServerTrailer{
+			Trailer: stream.Trailer(),
+			Err:     appErr,
+		})
+	}
+	return err
 }
 
 func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transport.Stream, srv *service, sd *StreamDesc, trInfo *traceInfo) (err error) {
@@ -1107,17 +1115,40 @@ func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transp
 	}
 	ctx := NewContextWithServerTransportStream(stream.Context(), stream)
 	ss := &serverStream{
-		ctx:   ctx,
-		t:     t,
-		s:     stream,
-		p:     &parser{r: stream},
-		codec: s.getCodec(stream.ContentSubtype()),
+		ctx:                   ctx,
+		t:                     t,
+		s:                     stream,
+		p:                     &parser{r: stream},
+		codec:                 s.getCodec(stream.ContentSubtype()),
 		maxReceiveMessageSize: s.opts.maxReceiveMessageSize,
 		maxSendMessageSize:    s.opts.maxSendMessageSize,
 		trInfo:                trInfo,
 		statsHandler:          sh,
 	}
 
+	ss.binlog = binarylog.GetMethodLogger(stream.Method())
+	if ss.binlog != nil {
+		md, _ := metadata.FromIncomingContext(ctx)
+		logEntry := &binarylog.ClientHeader{
+			Header:     md,
+			MethodName: stream.Method(),
+			PeerAddr:   nil,
+		}
+		if deadline, ok := ctx.Deadline(); ok {
+			logEntry.Timeout = time.Until(deadline)
+			if logEntry.Timeout < 0 {
+				logEntry.Timeout = 0
+			}
+		}
+		if a := md[":authority"]; len(a) > 0 {
+			logEntry.Authority = a[0]
+		}
+		if peer, ok := peer.FromContext(ss.Context()); ok {
+			logEntry.PeerAddr = peer.Addr
+		}
+		ss.binlog.Log(logEntry)
+	}
+
 	// If dc is set and matches the stream's compression, use it.  Otherwise, try
 	// to find a matching registered compressor for decomp.
 	if rc := stream.RecvCompress(); s.opts.dc != nil && s.opts.dc.Type() == rc {
@@ -1187,6 +1218,12 @@ func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transp
 			ss.mu.Unlock()
 		}
 		t.WriteStatus(ss.s, appStatus)
+		if ss.binlog != nil {
+			ss.binlog.Log(&binarylog.ServerTrailer{
+				Trailer: ss.s.Trailer(),
+				Err:     appErr,
+			})
+		}
 		// TODO: Should we log an error from WriteStatus here and below?
 		return appErr
 	}
@@ -1195,7 +1232,14 @@ func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transp
 		ss.trInfo.tr.LazyLog(stringer("OK"), false)
 		ss.mu.Unlock()
 	}
-	return t.WriteStatus(ss.s, status.New(codes.OK, ""))
+	err = t.WriteStatus(ss.s, statusOK)
+	if ss.binlog != nil {
+		ss.binlog.Log(&binarylog.ServerTrailer{
+			Trailer: ss.s.Trailer(),
+			Err:     appErr,
+		})
+	}
+	return err
 }
 
 func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Stream, trInfo *traceInfo) {
@@ -1224,47 +1268,33 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 	}
 	service := sm[:pos]
 	method := sm[pos+1:]
-	srv, ok := s.m[service]
-	if !ok {
-		if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
-			s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
+
+	srv, knownService := s.m[service]
+	if knownService {
+		if md, ok := srv.md[method]; ok {
+			s.processUnaryRPC(t, stream, srv, md, trInfo)
 			return
 		}
-		if trInfo != nil {
-			trInfo.tr.LazyLog(&fmtStringer{"Unknown service %v", []interface{}{service}}, true)
-			trInfo.tr.SetError()
-		}
-		errDesc := fmt.Sprintf("unknown service %v", service)
-		if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
-			if trInfo != nil {
-				trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
-				trInfo.tr.SetError()
-			}
-			grpclog.Warningf("grpc: Server.handleStream failed to write status: %v", err)
-		}
-		if trInfo != nil {
-			trInfo.tr.Finish()
+		if sd, ok := srv.sd[method]; ok {
+			s.processStreamingRPC(t, stream, srv, sd, trInfo)
+			return
 		}
-		return
 	}
-	// Unary RPC or Streaming RPC?
-	if md, ok := srv.md[method]; ok {
-		s.processUnaryRPC(t, stream, srv, md, trInfo)
+	// Unknown service, or known server unknown method.
+	if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
+		s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
 		return
 	}
-	if sd, ok := srv.sd[method]; ok {
-		s.processStreamingRPC(t, stream, srv, sd, trInfo)
-		return
+	var errDesc string
+	if !knownService {
+		errDesc = fmt.Sprintf("unknown service %v", service)
+	} else {
+		errDesc = fmt.Sprintf("unknown method %v for service %v", method, service)
 	}
 	if trInfo != nil {
-		trInfo.tr.LazyLog(&fmtStringer{"Unknown method %v", []interface{}{method}}, true)
+		trInfo.tr.LazyPrintf("%s", errDesc)
 		trInfo.tr.SetError()
 	}
-	if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
-		s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
-		return
-	}
-	errDesc := fmt.Sprintf("unknown method %v", method)
 	if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
@@ -1319,15 +1349,11 @@ func ServerTransportStreamFromContext(ctx context.Context) ServerTransportStream
 // pending RPCs on the client side will get notified by connection
 // errors.
 func (s *Server) Stop() {
-	s.quitOnce.Do(func() {
-		close(s.quit)
-	})
+	s.quit.Fire()
 
 	defer func() {
 		s.serveWG.Wait()
-		s.doneOnce.Do(func() {
-			close(s.done)
-		})
+		s.done.Fire()
 	}()
 
 	s.channelzRemoveOnce.Do(func() {
@@ -1364,15 +1390,8 @@ func (s *Server) Stop() {
 // accepting new connections and RPCs and blocks until all the pending RPCs are
 // finished.
 func (s *Server) GracefulStop() {
-	s.quitOnce.Do(func() {
-		close(s.quit)
-	})
-
-	defer func() {
-		s.doneOnce.Do(func() {
-			close(s.done)
-		})
-	}()
+	s.quit.Fire()
+	defer s.done.Fire()
 
 	s.channelzRemoveOnce.Do(func() {
 		if channelz.IsOn() {
@@ -1390,8 +1409,8 @@ func (s *Server) GracefulStop() {
 	}
 	s.lis = nil
 	if !s.drain {
-		for c := range s.conns {
-			c.(transport.ServerTransport).Drain()
+		for st := range s.conns {
+			st.Drain()
 		}
 		s.drain = true
 	}
@@ -1413,12 +1432,6 @@ func (s *Server) GracefulStop() {
 	s.mu.Unlock()
 }
 
-func init() {
-	internal.TestingUseHandlerImpl = func(arg interface{}) {
-		arg.(*Server).opts.useHandlerImpl = true
-	}
-}
-
 // contentSubtype must be lowercase
 // cannot return nil
 func (s *Server) getCodec(contentSubtype string) baseCodec {
@@ -1487,3 +1500,11 @@ func Method(ctx context.Context) (string, bool) {
 	}
 	return s.Method(), true
 }
+
+type channelzServer struct {
+	s *Server
+}
+
+func (c *channelzServer) ChannelzMetric() *channelz.ServerInternalMetric {
+	return c.s.channelzMetric()
+}
diff --git a/vendor/google.golang.org/grpc/service_config.go b/vendor/google.golang.org/grpc/service_config.go
index e0d73526..d0787f1e 100644
--- a/vendor/google.golang.org/grpc/service_config.go
+++ b/vendor/google.golang.org/grpc/service_config.go
@@ -25,8 +25,11 @@ import (
 	"strings"
 	"time"
 
+	"google.golang.org/grpc/balancer"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal"
+	"google.golang.org/grpc/serviceconfig"
 )
 
 const maxInt = int(^uint(0) >> 1)
@@ -61,6 +64,11 @@ type MethodConfig struct {
 	retryPolicy *retryPolicy
 }
 
+type lbConfig struct {
+	name string
+	cfg  serviceconfig.LoadBalancingConfig
+}
+
 // ServiceConfig is provided by the service provider and contains parameters for how
 // clients that connect to the service should behave.
 //
@@ -68,10 +76,18 @@ type MethodConfig struct {
 // through name resolver, as specified here
 // https://github.com/grpc/grpc/blob/master/doc/service_config.md
 type ServiceConfig struct {
-	// LB is the load balancer the service providers recommends. The balancer specified
-	// via grpc.WithBalancer will override this.
+	serviceconfig.Config
+
+	// LB is the load balancer the service providers recommends. The balancer
+	// specified via grpc.WithBalancer will override this.  This is deprecated;
+	// lbConfigs is preferred.  If lbConfig and LB are both present, lbConfig
+	// will be used.
 	LB *string
 
+	// lbConfig is the service config's load balancing configuration.  If
+	// lbConfig and LB are both present, lbConfig will be used.
+	lbConfig *lbConfig
+
 	// Methods contains a map for the methods in this service.  If there is an
 	// exact match for a method (i.e. /service/method) in the map, use the
 	// corresponding MethodConfig.  If there's no exact match, look for the
@@ -96,6 +112,18 @@ type ServiceConfig struct {
 	// If token_count is less than or equal to maxTokens / 2, then RPCs will not
 	// be retried and hedged RPCs will not be sent.
 	retryThrottling *retryThrottlingPolicy
+	// healthCheckConfig must be set as one of the requirement to enable LB channel
+	// health check.
+	healthCheckConfig *healthCheckConfig
+	// rawJSONString stores service config json string that get parsed into
+	// this service config struct.
+	rawJSONString string
+}
+
+// healthCheckConfig defines the go-native version of the LB channel health check config.
+type healthCheckConfig struct {
+	// serviceName is the service name to use in the health-checking request.
+	ServiceName string
 }
 
 // retryPolicy defines the go-native version of the retry policy defined by the
@@ -221,29 +249,72 @@ type jsonMC struct {
 	RetryPolicy             *jsonRetryPolicy
 }
 
+type loadBalancingConfig map[string]json.RawMessage
+
 // TODO(lyuxuan): delete this struct after cleaning up old service config implementation.
 type jsonSC struct {
 	LoadBalancingPolicy *string
+	LoadBalancingConfig *[]loadBalancingConfig
 	MethodConfig        *[]jsonMC
 	RetryThrottling     *retryThrottlingPolicy
+	HealthCheckConfig   *healthCheckConfig
 }
 
-func parseServiceConfig(js string) (ServiceConfig, error) {
+func init() {
+	internal.ParseServiceConfig = func(sc string) (interface{}, error) {
+		return parseServiceConfig(sc)
+	}
+}
+
+func parseServiceConfig(js string) (*ServiceConfig, error) {
+	if len(js) == 0 {
+		return nil, fmt.Errorf("no JSON service config provided")
+	}
 	var rsc jsonSC
 	err := json.Unmarshal([]byte(js), &rsc)
 	if err != nil {
 		grpclog.Warningf("grpc: parseServiceConfig error unmarshaling %s due to %v", js, err)
-		return ServiceConfig{}, err
+		return nil, err
 	}
 	sc := ServiceConfig{
-		LB:              rsc.LoadBalancingPolicy,
-		Methods:         make(map[string]MethodConfig),
-		retryThrottling: rsc.RetryThrottling,
+		LB:                rsc.LoadBalancingPolicy,
+		Methods:           make(map[string]MethodConfig),
+		retryThrottling:   rsc.RetryThrottling,
+		healthCheckConfig: rsc.HealthCheckConfig,
+		rawJSONString:     js,
 	}
-	if rsc.MethodConfig == nil {
-		return sc, nil
+	if rsc.LoadBalancingConfig != nil {
+		for i, lbcfg := range *rsc.LoadBalancingConfig {
+			if len(lbcfg) != 1 {
+				err := fmt.Errorf("invalid loadBalancingConfig: entry %v does not contain exactly 1 policy/config pair: %q", i, lbcfg)
+				grpclog.Warningf(err.Error())
+				return nil, err
+			}
+			var name string
+			var jsonCfg json.RawMessage
+			for name, jsonCfg = range lbcfg {
+			}
+			builder := balancer.Get(name)
+			if builder == nil {
+				continue
+			}
+			sc.lbConfig = &lbConfig{name: name}
+			if parser, ok := builder.(balancer.ConfigParser); ok {
+				var err error
+				sc.lbConfig.cfg, err = parser.ParseConfig(jsonCfg)
+				if err != nil {
+					return nil, fmt.Errorf("error parsing loadBalancingConfig for policy %q: %v", name, err)
+				}
+			} else if string(jsonCfg) != "{}" {
+				grpclog.Warningf("non-empty balancer configuration %q, but balancer does not implement ParseConfig", string(jsonCfg))
+			}
+			break
+		}
 	}
 
+	if rsc.MethodConfig == nil {
+		return &sc, nil
+	}
 	for _, m := range *rsc.MethodConfig {
 		if m.Name == nil {
 			continue
@@ -251,7 +322,7 @@ func parseServiceConfig(js string) (ServiceConfig, error) {
 		d, err := parseDuration(m.Timeout)
 		if err != nil {
 			grpclog.Warningf("grpc: parseServiceConfig error unmarshaling %s due to %v", js, err)
-			return ServiceConfig{}, err
+			return nil, err
 		}
 
 		mc := MethodConfig{
@@ -260,7 +331,7 @@ func parseServiceConfig(js string) (ServiceConfig, error) {
 		}
 		if mc.retryPolicy, err = convertRetryPolicy(m.RetryPolicy); err != nil {
 			grpclog.Warningf("grpc: parseServiceConfig error unmarshaling %s due to %v", js, err)
-			return ServiceConfig{}, err
+			return nil, err
 		}
 		if m.MaxRequestMessageBytes != nil {
 			if *m.MaxRequestMessageBytes > int64(maxInt) {
@@ -284,14 +355,14 @@ func parseServiceConfig(js string) (ServiceConfig, error) {
 	}
 
 	if sc.retryThrottling != nil {
-		if sc.retryThrottling.MaxTokens <= 0 ||
-			sc.retryThrottling.MaxTokens >= 1000 ||
-			sc.retryThrottling.TokenRatio <= 0 {
-			// Illegal throttling config; disable throttling.
-			sc.retryThrottling = nil
+		if mt := sc.retryThrottling.MaxTokens; mt <= 0 || mt > 1000 {
+			return nil, fmt.Errorf("invalid retry throttling config: maxTokens (%v) out of range (0, 1000]", mt)
+		}
+		if tr := sc.retryThrottling.TokenRatio; tr <= 0 {
+			return nil, fmt.Errorf("invalid retry throttling config: tokenRatio (%v) may not be negative", tr)
 		}
 	}
-	return sc, nil
+	return &sc, nil
 }
 
 func convertRetryPolicy(jrp *jsonRetryPolicy) (p *retryPolicy, err error) {
diff --git a/vendor/google.golang.org/grpc/serviceconfig/serviceconfig.go b/vendor/google.golang.org/grpc/serviceconfig/serviceconfig.go
new file mode 100644
index 00000000..53b27875
--- /dev/null
+++ b/vendor/google.golang.org/grpc/serviceconfig/serviceconfig.go
@@ -0,0 +1,48 @@
+/*
+ *
+ * Copyright 2019 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package serviceconfig defines types and methods for operating on gRPC
+// service configs.
+//
+// This package is EXPERIMENTAL.
+package serviceconfig
+
+import (
+	"google.golang.org/grpc/internal"
+)
+
+// Config represents an opaque data structure holding a service config.
+type Config interface {
+	isConfig()
+}
+
+// LoadBalancingConfig represents an opaque data structure holding a load
+// balancer config.
+type LoadBalancingConfig interface {
+	isLoadBalancingConfig()
+}
+
+// Parse parses the JSON service config provided into an internal form or
+// returns an error if the config is invalid.
+func Parse(ServiceConfigJSON string) (Config, error) {
+	c, err := internal.ParseServiceConfig(ServiceConfigJSON)
+	if err != nil {
+		return nil, err
+	}
+	return c.(Config), err
+}
diff --git a/vendor/google.golang.org/grpc/stats/handlers.go b/vendor/google.golang.org/grpc/stats/handlers.go
index 05b384c6..dc03731e 100644
--- a/vendor/google.golang.org/grpc/stats/handlers.go
+++ b/vendor/google.golang.org/grpc/stats/handlers.go
@@ -19,9 +19,8 @@
 package stats
 
 import (
+	"context"
 	"net"
-
-	"golang.org/x/net/context"
 )
 
 // ConnTagInfo defines the relevant information needed by connection context tagger.
diff --git a/vendor/google.golang.org/grpc/stats/stats.go b/vendor/google.golang.org/grpc/stats/stats.go
index 3f13190a..f3f593c8 100644
--- a/vendor/google.golang.org/grpc/stats/stats.go
+++ b/vendor/google.golang.org/grpc/stats/stats.go
@@ -24,10 +24,11 @@
 package stats // import "google.golang.org/grpc/stats"
 
 import (
+	"context"
 	"net"
 	"time"
 
-	"golang.org/x/net/context"
+	"google.golang.org/grpc/metadata"
 )
 
 // RPCStats contains stats information about RPCs.
@@ -173,6 +174,9 @@ type End struct {
 	BeginTime time.Time
 	// EndTime is the time when the RPC ends.
 	EndTime time.Time
+	// Trailer contains the trailer metadata received from the server. This
+	// field is only valid if this End is from the client side.
+	Trailer metadata.MD
 	// Error is the error the RPC ended with. It is an error generated from
 	// status.Status and can be converted back to status.Status using
 	// status.FromError if non-nil.
diff --git a/vendor/google.golang.org/grpc/status/go17.go b/vendor/google.golang.org/grpc/status/go17.go
deleted file mode 100644
index 09021514..00000000
--- a/vendor/google.golang.org/grpc/status/go17.go
+++ /dev/null
@@ -1,44 +0,0 @@
-// +build go1.7
-
-/*
- *
- * Copyright 2018 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package status
-
-import (
-	"context"
-
-	netctx "golang.org/x/net/context"
-	"google.golang.org/grpc/codes"
-)
-
-// FromContextError converts a context error into a Status.  It returns a
-// Status with codes.OK if err is nil, or a Status with codes.Unknown if err is
-// non-nil and not a context error.
-func FromContextError(err error) *Status {
-	switch err {
-	case nil:
-		return New(codes.OK, "")
-	case context.DeadlineExceeded, netctx.DeadlineExceeded:
-		return New(codes.DeadlineExceeded, err.Error())
-	case context.Canceled, netctx.Canceled:
-		return New(codes.Canceled, err.Error())
-	default:
-		return New(codes.Unknown, err.Error())
-	}
-}
diff --git a/vendor/google.golang.org/grpc/status/status.go b/vendor/google.golang.org/grpc/status/status.go
index 9c61b094..a1348e9b 100644
--- a/vendor/google.golang.org/grpc/status/status.go
+++ b/vendor/google.golang.org/grpc/status/status.go
@@ -28,6 +28,7 @@
 package status
 
 import (
+	"context"
 	"errors"
 	"fmt"
 
@@ -35,8 +36,15 @@ import (
 	"github.com/golang/protobuf/ptypes"
 	spb "google.golang.org/genproto/googleapis/rpc/status"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/internal"
 )
 
+func init() {
+	internal.StatusRawProto = statusRawProto
+}
+
+func statusRawProto(s *Status) *spb.Status { return s.s }
+
 // statusError is an alias of a status proto.  It implements error and Status,
 // and a nil statusError should never be returned by this package.
 type statusError spb.Status
@@ -50,6 +58,17 @@ func (se *statusError) GRPCStatus() *Status {
 	return &Status{s: (*spb.Status)(se)}
 }
 
+// Is implements future error.Is functionality.
+// A statusError is equivalent if the code and message are identical.
+func (se *statusError) Is(target error) bool {
+	tse, ok := target.(*statusError)
+	if !ok {
+		return false
+	}
+
+	return proto.Equal((*spb.Status)(se), (*spb.Status)(tse))
+}
+
 // Status represents an RPC status code, message, and details.  It is immutable
 // and should be created with New, Newf, or FromProto.
 type Status struct {
@@ -124,9 +143,11 @@ func FromProto(s *spb.Status) *Status {
 // Status is returned with codes.Unknown and the original error message.
 func FromError(err error) (s *Status, ok bool) {
 	if err == nil {
-		return &Status{s: &spb.Status{Code: int32(codes.OK)}}, true
+		return nil, true
 	}
-	if se, ok := err.(interface{ GRPCStatus() *Status }); ok {
+	if se, ok := err.(interface {
+		GRPCStatus() *Status
+	}); ok {
 		return se.GRPCStatus(), true
 	}
 	return New(codes.Unknown, err.Error()), false
@@ -182,8 +203,26 @@ func Code(err error) codes.Code {
 	if err == nil {
 		return codes.OK
 	}
-	if se, ok := err.(interface{ GRPCStatus() *Status }); ok {
+	if se, ok := err.(interface {
+		GRPCStatus() *Status
+	}); ok {
 		return se.GRPCStatus().Code()
 	}
 	return codes.Unknown
 }
+
+// FromContextError converts a context error into a Status.  It returns a
+// Status with codes.OK if err is nil, or a Status with codes.Unknown if err is
+// non-nil and not a context error.
+func FromContextError(err error) *Status {
+	switch err {
+	case nil:
+		return nil
+	case context.DeadlineExceeded:
+		return New(codes.DeadlineExceeded, err.Error())
+	case context.Canceled:
+		return New(codes.Canceled, err.Error())
+	default:
+		return New(codes.Unknown, err.Error())
+	}
+}
diff --git a/vendor/google.golang.org/grpc/stream.go b/vendor/google.golang.org/grpc/stream.go
index 65d45a1d..134a624a 100644
--- a/vendor/google.golang.org/grpc/stream.go
+++ b/vendor/google.golang.org/grpc/stream.go
@@ -19,6 +19,7 @@
 package grpc
 
 import (
+	"context"
 	"errors"
 	"io"
 	"math"
@@ -26,16 +27,18 @@ import (
 	"sync"
 	"time"
 
-	"golang.org/x/net/context"
 	"golang.org/x/net/trace"
 	"google.golang.org/grpc/balancer"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/encoding"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/balancerload"
+	"google.golang.org/grpc/internal/binarylog"
 	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/internal/grpcrand"
 	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
 )
@@ -82,7 +85,8 @@ type ClientStream interface {
 	// stream.Recv has returned a non-nil error (including io.EOF).
 	Trailer() metadata.MD
 	// CloseSend closes the send direction of the stream. It closes the stream
-	// when non-nil error is met.
+	// when non-nil error is met. It is also not safe to call CloseSend
+	// concurrently with SendMsg.
 	CloseSend() error
 	// Context returns the context for this stream.
 	//
@@ -105,7 +109,8 @@ type ClientStream interface {
 	//
 	// It is safe to have a goroutine calling SendMsg and another goroutine
 	// calling RecvMsg on the same stream at the same time, but it is not safe
-	// to call SendMsg on the same stream in different goroutines.
+	// to call SendMsg on the same stream in different goroutines. It is also
+	// not safe to call CloseSend concurrently with SendMsg.
 	SendMsg(m interface{}) error
 	// RecvMsg blocks until it receives a message into m or the stream is
 	// done. It returns io.EOF when the stream completes successfully. On
@@ -160,6 +165,11 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		}()
 	}
 	c := defaultCallInfo()
+	// Provide an opportunity for the first RPC to see the first service config
+	// provided by the resolver.
+	if err := cc.waitForResolvedAddrs(ctx); err != nil {
+		return nil, err
+	}
 	mc := cc.GetMethodConfig(method)
 	if mc.WaitForReady != nil {
 		c.failFast = !*mc.WaitForReady
@@ -220,17 +230,21 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 	if c.creds != nil {
 		callHdr.Creds = c.creds
 	}
-	var trInfo traceInfo
+	var trInfo *traceInfo
 	if EnableTracing {
-		trInfo.tr = trace.New("grpc.Sent."+methodFamily(method), method)
-		trInfo.firstLine.client = true
+		trInfo = &traceInfo{
+			tr: trace.New("grpc.Sent."+methodFamily(method), method),
+			firstLine: firstLine{
+				client: true,
+			},
+		}
 		if deadline, ok := ctx.Deadline(); ok {
-			trInfo.firstLine.deadline = deadline.Sub(time.Now())
+			trInfo.firstLine.deadline = time.Until(deadline)
 		}
 		trInfo.tr.LazyLog(&trInfo.firstLine, false)
 		ctx = trace.NewContext(ctx, trInfo.tr)
 	}
-	ctx = newContextWithRPCInfo(ctx, c.failFast)
+	ctx = newContextWithRPCInfo(ctx, c.failFast, c.codec, cp, comp)
 	sh := cc.dopts.copts.StatsHandler
 	var beginTime time.Time
 	if sh != nil {
@@ -262,6 +276,7 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 	if !cc.dopts.disableRetry {
 		cs.retryThrottler = cc.retryThrottler.Load().(*retryThrottler)
 	}
+	cs.binlog = binarylog.GetMethodLogger(method)
 
 	cs.callInfo.stream = cs
 	// Only this initial attempt has stats/tracing.
@@ -277,6 +292,23 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		return nil, err
 	}
 
+	if cs.binlog != nil {
+		md, _ := metadata.FromOutgoingContext(ctx)
+		logEntry := &binarylog.ClientHeader{
+			OnClientSide: true,
+			Header:       md,
+			MethodName:   method,
+			Authority:    cs.cc.authority,
+		}
+		if deadline, ok := ctx.Deadline(); ok {
+			logEntry.Timeout = time.Until(deadline)
+			if logEntry.Timeout < 0 {
+				logEntry.Timeout = 0
+			}
+		}
+		cs.binlog.Log(logEntry)
+	}
+
 	if desc != unaryStreamDesc {
 		// Listen on cc and stream contexts to cleanup when the user closes the
 		// ClientConn or cancels the stream context.  In all other cases, an error
@@ -295,13 +327,23 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 	return cs, nil
 }
 
-func (cs *clientStream) newAttemptLocked(sh stats.Handler, trInfo traceInfo) error {
-	cs.attempt = &csAttempt{
+// newAttemptLocked creates a new attempt with a transport.
+// If it succeeds, then it replaces clientStream's attempt with this new attempt.
+func (cs *clientStream) newAttemptLocked(sh stats.Handler, trInfo *traceInfo) (retErr error) {
+	newAttempt := &csAttempt{
 		cs:           cs,
 		dc:           cs.cc.dopts.dc,
 		statsHandler: sh,
 		trInfo:       trInfo,
 	}
+	defer func() {
+		if retErr != nil {
+			// This attempt is not set in the clientStream, so it's finish won't
+			// be called. Call it here for stats and trace in case they are not
+			// nil.
+			newAttempt.finish(retErr)
+		}
+	}()
 
 	if err := cs.ctx.Err(); err != nil {
 		return toRPCErr(err)
@@ -310,8 +352,12 @@ func (cs *clientStream) newAttemptLocked(sh stats.Handler, trInfo traceInfo) err
 	if err != nil {
 		return err
 	}
-	cs.attempt.t = t
-	cs.attempt.done = done
+	if trInfo != nil {
+		trInfo.firstLine.SetRemoteAddr(t.RemoteAddr())
+	}
+	newAttempt.t = t
+	newAttempt.done = done
+	cs.attempt = newAttempt
 	return nil
 }
 
@@ -350,12 +396,28 @@ type clientStream struct {
 
 	retryThrottler *retryThrottler // The throttler active when the RPC began.
 
+	binlog *binarylog.MethodLogger // Binary logger, can be nil.
+	// serverHeaderBinlogged is a boolean for whether server header has been
+	// logged. Server header will be logged when the first time one of those
+	// happens: stream.Header(), stream.Recv().
+	//
+	// It's only read and used by Recv() and Header(), so it doesn't need to be
+	// synchronized.
+	serverHeaderBinlogged bool
+
 	mu                      sync.Mutex
-	firstAttempt            bool       // if true, transparent retry is valid
-	numRetries              int        // exclusive of transparent retry attempt(s)
-	numRetriesSincePushback int        // retries since pushback; to reset backoff
-	finished                bool       // TODO: replace with atomic cmpxchg or sync.Once?
-	attempt                 *csAttempt // the active client stream attempt
+	firstAttempt            bool // if true, transparent retry is valid
+	numRetries              int  // exclusive of transparent retry attempt(s)
+	numRetriesSincePushback int  // retries since pushback; to reset backoff
+	finished                bool // TODO: replace with atomic cmpxchg or sync.Once?
+	// attempt is the active client stream attempt.
+	// The only place where it is written is the newAttemptLocked method and this method never writes nil.
+	// So, attempt can be nil only inside newClientStream function when clientStream is first created.
+	// One of the first things done after clientStream's creation, is to call newAttemptLocked which either
+	// assigns a non nil value to the attempt or returns an error. If an error is returned from newAttemptLocked,
+	// then newClientStream calls finish on the clientStream and returns. So, finish method is the only
+	// place where we need to check if the attempt is nil.
+	attempt *csAttempt
 	// TODO(hedging): hedging will have multiple attempts simultaneously.
 	committed  bool                       // active attempt committed for retry?
 	buffer     []func(a *csAttempt) error // operations to replay on retry
@@ -377,9 +439,10 @@ type csAttempt struct {
 	decompSet bool
 
 	mu sync.Mutex // guards trInfo.tr
+	// trInfo may be nil (if EnableTracing is false).
 	// trInfo.tr is set when created (if EnableTracing is true),
 	// and cleared when the finish method is called.
-	trInfo traceInfo
+	trInfo *traceInfo
 
 	statsHandler stats.Handler
 }
@@ -412,8 +475,8 @@ func (cs *clientStream) shouldRetry(err error) error {
 	if cs.attempt.s != nil {
 		<-cs.attempt.s.Done()
 	}
-	if cs.firstAttempt && !cs.callInfo.failFast && (cs.attempt.s == nil || cs.attempt.s.Unprocessed()) {
-		// First attempt, wait-for-ready, stream unprocessed: transparently retry.
+	if cs.firstAttempt && (cs.attempt.s == nil || cs.attempt.s.Unprocessed()) {
+		// First attempt, stream unprocessed: transparently retry.
 		cs.firstAttempt = false
 		return nil
 	}
@@ -425,10 +488,7 @@ func (cs *clientStream) shouldRetry(err error) error {
 	pushback := 0
 	hasPushback := false
 	if cs.attempt.s != nil {
-		if to, toErr := cs.attempt.s.TrailersOnly(); toErr != nil {
-			// Context error; stop now.
-			return toErr
-		} else if !to {
+		if to, toErr := cs.attempt.s.TrailersOnly(); toErr != nil || !to {
 			return err
 		}
 
@@ -506,7 +566,7 @@ func (cs *clientStream) retryLocked(lastErr error) error {
 			cs.commitAttemptLocked()
 			return err
 		}
-		if err := cs.newAttemptLocked(nil, traceInfo{}); err != nil {
+		if err := cs.newAttemptLocked(nil, nil); err != nil {
 			return err
 		}
 		if lastErr = cs.replayBufferLocked(); lastErr == nil {
@@ -561,6 +621,20 @@ func (cs *clientStream) Header() (metadata.MD, error) {
 	}, cs.commitAttemptLocked)
 	if err != nil {
 		cs.finish(err)
+		return nil, err
+	}
+	if cs.binlog != nil && !cs.serverHeaderBinlogged {
+		// Only log if binary log is on and header has not been logged.
+		logEntry := &binarylog.ServerHeader{
+			OnClientSide: true,
+			Header:       m,
+			PeerAddr:     nil,
+		}
+		if peer, ok := peer.FromContext(cs.Context()); ok {
+			logEntry.PeerAddr = peer.Addr
+		}
+		cs.binlog.Log(logEntry)
+		cs.serverHeaderBinlogged = true
 	}
 	return m, err
 }
@@ -620,19 +694,18 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 	if !cs.desc.ClientStreams {
 		cs.sentLast = true
 	}
-	data, err := encode(cs.codec, m)
-	if err != nil {
-		return err
-	}
-	compData, err := compress(data, cs.cp, cs.comp)
+
+	// load hdr, payload, data
+	hdr, payload, data, err := prepareMsg(m, cs.codec, cs.cp, cs.comp)
 	if err != nil {
 		return err
 	}
-	hdr, payload := msgHeader(data, compData)
+
 	// TODO(dfawley): should we be checking len(data) instead?
 	if len(payload) > *cs.callInfo.maxSendMessageSize {
 		return status.Errorf(codes.ResourceExhausted, "trying to send message larger than max (%d vs. %d)", len(payload), *cs.callInfo.maxSendMessageSize)
 	}
+	msgBytes := data // Store the pointer before setting to nil. For binary logging.
 	op := func(a *csAttempt) error {
 		err := a.sendMsg(m, hdr, payload, data)
 		// nil out the message and uncomp when replaying; they are only needed for
@@ -640,16 +713,53 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 		m, data = nil, nil
 		return err
 	}
-	return cs.withRetry(op, func() { cs.bufferForRetryLocked(len(hdr)+len(payload), op) })
+	err = cs.withRetry(op, func() { cs.bufferForRetryLocked(len(hdr)+len(payload), op) })
+	if cs.binlog != nil && err == nil {
+		cs.binlog.Log(&binarylog.ClientMessage{
+			OnClientSide: true,
+			Message:      msgBytes,
+		})
+	}
+	return
 }
 
 func (cs *clientStream) RecvMsg(m interface{}) error {
+	if cs.binlog != nil && !cs.serverHeaderBinlogged {
+		// Call Header() to binary log header if it's not already logged.
+		cs.Header()
+	}
+	var recvInfo *payloadInfo
+	if cs.binlog != nil {
+		recvInfo = &payloadInfo{}
+	}
 	err := cs.withRetry(func(a *csAttempt) error {
-		return a.recvMsg(m)
+		return a.recvMsg(m, recvInfo)
 	}, cs.commitAttemptLocked)
+	if cs.binlog != nil && err == nil {
+		cs.binlog.Log(&binarylog.ServerMessage{
+			OnClientSide: true,
+			Message:      recvInfo.uncompressedBytes,
+		})
+	}
 	if err != nil || !cs.desc.ServerStreams {
 		// err != nil or non-server-streaming indicates end of stream.
 		cs.finish(err)
+
+		if cs.binlog != nil {
+			// finish will not log Trailer. Log Trailer here.
+			logEntry := &binarylog.ServerTrailer{
+				OnClientSide: true,
+				Trailer:      cs.Trailer(),
+				Err:          err,
+			}
+			if logEntry.Err == io.EOF {
+				logEntry.Err = nil
+			}
+			if peer, ok := peer.FromContext(cs.Context()); ok {
+				logEntry.PeerAddr = peer.Addr
+			}
+			cs.binlog.Log(logEntry)
+		}
 	}
 	return err
 }
@@ -660,8 +770,20 @@ func (cs *clientStream) CloseSend() error {
 		return nil
 	}
 	cs.sentLast = true
-	op := func(a *csAttempt) error { return a.t.Write(a.s, nil, nil, &transport.Options{Last: true}) }
+	op := func(a *csAttempt) error {
+		a.t.Write(a.s, nil, nil, &transport.Options{Last: true})
+		// Always return nil; io.EOF is the only error that might make sense
+		// instead, but there is no need to signal the client to call RecvMsg
+		// as the only use left for the stream after CloseSend is to call
+		// RecvMsg.  This also matches historical behavior.
+		return nil
+	}
 	cs.withRetry(op, func() { cs.bufferForRetryLocked(0, op) })
+	if cs.binlog != nil {
+		cs.binlog.Log(&binarylog.ClientHalfClose{
+			OnClientSide: true,
+		})
+	}
 	// We never returned an error here for reasons.
 	return nil
 }
@@ -679,6 +801,16 @@ func (cs *clientStream) finish(err error) {
 	cs.finished = true
 	cs.commitAttemptLocked()
 	cs.mu.Unlock()
+	// For binary logging. only log cancel in finish (could be caused by RPC ctx
+	// canceled or ClientConn closed). Trailer will be logged in RecvMsg.
+	//
+	// Only one of cancel or trailer needs to be logged. In the cases where
+	// users don't call RecvMsg, users must have already canceled the RPC.
+	if cs.binlog != nil && status.Code(err) == codes.Canceled {
+		cs.binlog.Log(&binarylog.Cancel{
+			OnClientSide: true,
+		})
+	}
 	if err == nil {
 		cs.retryThrottler.successfulRPC()
 	}
@@ -691,11 +823,11 @@ func (cs *clientStream) finish(err error) {
 	}
 	if cs.attempt != nil {
 		cs.attempt.finish(err)
-	}
-	// after functions all rely upon having a stream.
-	if cs.attempt.s != nil {
-		for _, o := range cs.opts {
-			o.after(cs.callInfo)
+		// after functions all rely upon having a stream.
+		if cs.attempt.s != nil {
+			for _, o := range cs.opts {
+				o.after(cs.callInfo)
+			}
 		}
 	}
 	cs.cancel()
@@ -703,7 +835,7 @@ func (cs *clientStream) finish(err error) {
 
 func (a *csAttempt) sendMsg(m interface{}, hdr, payld, data []byte) error {
 	cs := a.cs
-	if EnableTracing {
+	if a.trInfo != nil {
 		a.mu.Lock()
 		if a.trInfo.tr != nil {
 			a.trInfo.tr.LazyLog(&payload{sent: true, msg: m}, true)
@@ -728,14 +860,12 @@ func (a *csAttempt) sendMsg(m interface{}, hdr, payld, data []byte) error {
 	return nil
 }
 
-func (a *csAttempt) recvMsg(m interface{}) (err error) {
+func (a *csAttempt) recvMsg(m interface{}, payInfo *payloadInfo) (err error) {
 	cs := a.cs
-	var inPayload *stats.InPayload
-	if a.statsHandler != nil {
-		inPayload = &stats.InPayload{
-			Client: true,
-		}
+	if a.statsHandler != nil && payInfo == nil {
+		payInfo = &payloadInfo{}
 	}
+
 	if !a.decompSet {
 		// Block until we receive headers containing received message encoding.
 		if ct := a.s.RecvCompress(); ct != "" && ct != encoding.Identity {
@@ -752,7 +882,7 @@ func (a *csAttempt) recvMsg(m interface{}) (err error) {
 		// Only initialize this state once per stream.
 		a.decompSet = true
 	}
-	err = recv(a.p, cs.codec, a.s, a.dc, m, *cs.callInfo.maxReceiveMessageSize, inPayload, a.decomp)
+	err = recv(a.p, cs.codec, a.s, a.dc, m, *cs.callInfo.maxReceiveMessageSize, payInfo, a.decomp)
 	if err != nil {
 		if err == io.EOF {
 			if statusErr := a.s.Status().Err(); statusErr != nil {
@@ -762,15 +892,23 @@ func (a *csAttempt) recvMsg(m interface{}) (err error) {
 		}
 		return toRPCErr(err)
 	}
-	if EnableTracing {
+	if a.trInfo != nil {
 		a.mu.Lock()
 		if a.trInfo.tr != nil {
 			a.trInfo.tr.LazyLog(&payload{sent: false, msg: m}, true)
 		}
 		a.mu.Unlock()
 	}
-	if inPayload != nil {
-		a.statsHandler.HandleRPC(cs.ctx, inPayload)
+	if a.statsHandler != nil {
+		a.statsHandler.HandleRPC(cs.ctx, &stats.InPayload{
+			Client:   true,
+			RecvTime: time.Now(),
+			Payload:  m,
+			// TODO truncate large payload.
+			Data:       payInfo.uncompressedBytes,
+			WireLength: payInfo.wireLength,
+			Length:     len(payInfo.uncompressedBytes),
+		})
 	}
 	if channelz.IsOn() {
 		a.t.IncrMsgRecv()
@@ -779,7 +917,6 @@ func (a *csAttempt) recvMsg(m interface{}) (err error) {
 		// Subsequent messages should be received by subsequent RecvMsg calls.
 		return nil
 	}
-
 	// Special handling for non-server-stream rpcs.
 	// This recv expects EOF or errors, so we don't collect inPayload.
 	err = recv(a.p, cs.codec, a.s, a.dc, m, *cs.callInfo.maxReceiveMessageSize, nil, a.decomp)
@@ -803,8 +940,10 @@ func (a *csAttempt) finish(err error) {
 		// Ending a stream with EOF indicates a success.
 		err = nil
 	}
+	var tr metadata.MD
 	if a.s != nil {
 		a.t.CloseStream(a.s, err)
+		tr = a.s.Trailer()
 	}
 
 	if a.done != nil {
@@ -814,8 +953,10 @@ func (a *csAttempt) finish(err error) {
 		}
 		a.done(balancer.DoneInfo{
 			Err:           err,
+			Trailer:       tr,
 			BytesSent:     a.s != nil,
 			BytesReceived: br,
+			ServerLoad:    balancerload.Parse(tr),
 		})
 	}
 	if a.statsHandler != nil {
@@ -823,11 +964,12 @@ func (a *csAttempt) finish(err error) {
 			Client:    true,
 			BeginTime: a.cs.beginTime,
 			EndTime:   time.Now(),
+			Trailer:   tr,
 			Error:     err,
 		}
 		a.statsHandler.HandleRPC(a.cs.ctx, end)
 	}
-	if a.trInfo.tr != nil {
+	if a.trInfo != nil && a.trInfo.tr != nil {
 		if err == nil {
 			a.trInfo.tr.LazyPrintf("RPC: [OK]")
 		} else {
@@ -840,6 +982,295 @@ func (a *csAttempt) finish(err error) {
 	a.mu.Unlock()
 }
 
+// newClientStream creates a ClientStream with the specified transport, on the
+// given addrConn.
+//
+// It's expected that the given transport is either the same one in addrConn, or
+// is already closed. To avoid race, transport is specified separately, instead
+// of using ac.transpot.
+//
+// Main difference between this and ClientConn.NewStream:
+// - no retry
+// - no service config (or wait for service config)
+// - no tracing or stats
+func newNonRetryClientStream(ctx context.Context, desc *StreamDesc, method string, t transport.ClientTransport, ac *addrConn, opts ...CallOption) (_ ClientStream, err error) {
+	if t == nil {
+		// TODO: return RPC error here?
+		return nil, errors.New("transport provided is nil")
+	}
+	// defaultCallInfo contains unnecessary info(i.e. failfast, maxRetryRPCBufferSize), so we just initialize an empty struct.
+	c := &callInfo{}
+
+	// Possible context leak:
+	// The cancel function for the child context we create will only be called
+	// when RecvMsg returns a non-nil error, if the ClientConn is closed, or if
+	// an error is generated by SendMsg.
+	// https://github.com/grpc/grpc-go/issues/1818.
+	ctx, cancel := context.WithCancel(ctx)
+	defer func() {
+		if err != nil {
+			cancel()
+		}
+	}()
+
+	for _, o := range opts {
+		if err := o.before(c); err != nil {
+			return nil, toRPCErr(err)
+		}
+	}
+	c.maxReceiveMessageSize = getMaxSize(nil, c.maxReceiveMessageSize, defaultClientMaxReceiveMessageSize)
+	c.maxSendMessageSize = getMaxSize(nil, c.maxSendMessageSize, defaultServerMaxSendMessageSize)
+	if err := setCallInfoCodec(c); err != nil {
+		return nil, err
+	}
+
+	callHdr := &transport.CallHdr{
+		Host:           ac.cc.authority,
+		Method:         method,
+		ContentSubtype: c.contentSubtype,
+	}
+
+	// Set our outgoing compression according to the UseCompressor CallOption, if
+	// set.  In that case, also find the compressor from the encoding package.
+	// Otherwise, use the compressor configured by the WithCompressor DialOption,
+	// if set.
+	var cp Compressor
+	var comp encoding.Compressor
+	if ct := c.compressorType; ct != "" {
+		callHdr.SendCompress = ct
+		if ct != encoding.Identity {
+			comp = encoding.GetCompressor(ct)
+			if comp == nil {
+				return nil, status.Errorf(codes.Internal, "grpc: Compressor is not installed for requested grpc-encoding %q", ct)
+			}
+		}
+	} else if ac.cc.dopts.cp != nil {
+		callHdr.SendCompress = ac.cc.dopts.cp.Type()
+		cp = ac.cc.dopts.cp
+	}
+	if c.creds != nil {
+		callHdr.Creds = c.creds
+	}
+
+	// Use a special addrConnStream to avoid retry.
+	as := &addrConnStream{
+		callHdr:  callHdr,
+		ac:       ac,
+		ctx:      ctx,
+		cancel:   cancel,
+		opts:     opts,
+		callInfo: c,
+		desc:     desc,
+		codec:    c.codec,
+		cp:       cp,
+		comp:     comp,
+		t:        t,
+	}
+
+	as.callInfo.stream = as
+	s, err := as.t.NewStream(as.ctx, as.callHdr)
+	if err != nil {
+		err = toRPCErr(err)
+		return nil, err
+	}
+	as.s = s
+	as.p = &parser{r: s}
+	ac.incrCallsStarted()
+	if desc != unaryStreamDesc {
+		// Listen on cc and stream contexts to cleanup when the user closes the
+		// ClientConn or cancels the stream context.  In all other cases, an error
+		// should already be injected into the recv buffer by the transport, which
+		// the client will eventually receive, and then we will cancel the stream's
+		// context in clientStream.finish.
+		go func() {
+			select {
+			case <-ac.ctx.Done():
+				as.finish(status.Error(codes.Canceled, "grpc: the SubConn is closing"))
+			case <-ctx.Done():
+				as.finish(toRPCErr(ctx.Err()))
+			}
+		}()
+	}
+	return as, nil
+}
+
+type addrConnStream struct {
+	s         *transport.Stream
+	ac        *addrConn
+	callHdr   *transport.CallHdr
+	cancel    context.CancelFunc
+	opts      []CallOption
+	callInfo  *callInfo
+	t         transport.ClientTransport
+	ctx       context.Context
+	sentLast  bool
+	desc      *StreamDesc
+	codec     baseCodec
+	cp        Compressor
+	comp      encoding.Compressor
+	decompSet bool
+	dc        Decompressor
+	decomp    encoding.Compressor
+	p         *parser
+	mu        sync.Mutex
+	finished  bool
+}
+
+func (as *addrConnStream) Header() (metadata.MD, error) {
+	m, err := as.s.Header()
+	if err != nil {
+		as.finish(toRPCErr(err))
+	}
+	return m, err
+}
+
+func (as *addrConnStream) Trailer() metadata.MD {
+	return as.s.Trailer()
+}
+
+func (as *addrConnStream) CloseSend() error {
+	if as.sentLast {
+		// TODO: return an error and finish the stream instead, due to API misuse?
+		return nil
+	}
+	as.sentLast = true
+
+	as.t.Write(as.s, nil, nil, &transport.Options{Last: true})
+	// Always return nil; io.EOF is the only error that might make sense
+	// instead, but there is no need to signal the client to call RecvMsg
+	// as the only use left for the stream after CloseSend is to call
+	// RecvMsg.  This also matches historical behavior.
+	return nil
+}
+
+func (as *addrConnStream) Context() context.Context {
+	return as.s.Context()
+}
+
+func (as *addrConnStream) SendMsg(m interface{}) (err error) {
+	defer func() {
+		if err != nil && err != io.EOF {
+			// Call finish on the client stream for errors generated by this SendMsg
+			// call, as these indicate problems created by this client.  (Transport
+			// errors are converted to an io.EOF error in csAttempt.sendMsg; the real
+			// error will be returned from RecvMsg eventually in that case, or be
+			// retried.)
+			as.finish(err)
+		}
+	}()
+	if as.sentLast {
+		return status.Errorf(codes.Internal, "SendMsg called after CloseSend")
+	}
+	if !as.desc.ClientStreams {
+		as.sentLast = true
+	}
+
+	// load hdr, payload, data
+	hdr, payld, _, err := prepareMsg(m, as.codec, as.cp, as.comp)
+	if err != nil {
+		return err
+	}
+
+	// TODO(dfawley): should we be checking len(data) instead?
+	if len(payld) > *as.callInfo.maxSendMessageSize {
+		return status.Errorf(codes.ResourceExhausted, "trying to send message larger than max (%d vs. %d)", len(payld), *as.callInfo.maxSendMessageSize)
+	}
+
+	if err := as.t.Write(as.s, hdr, payld, &transport.Options{Last: !as.desc.ClientStreams}); err != nil {
+		if !as.desc.ClientStreams {
+			// For non-client-streaming RPCs, we return nil instead of EOF on error
+			// because the generated code requires it.  finish is not called; RecvMsg()
+			// will call it with the stream's status independently.
+			return nil
+		}
+		return io.EOF
+	}
+
+	if channelz.IsOn() {
+		as.t.IncrMsgSent()
+	}
+	return nil
+}
+
+func (as *addrConnStream) RecvMsg(m interface{}) (err error) {
+	defer func() {
+		if err != nil || !as.desc.ServerStreams {
+			// err != nil or non-server-streaming indicates end of stream.
+			as.finish(err)
+		}
+	}()
+
+	if !as.decompSet {
+		// Block until we receive headers containing received message encoding.
+		if ct := as.s.RecvCompress(); ct != "" && ct != encoding.Identity {
+			if as.dc == nil || as.dc.Type() != ct {
+				// No configured decompressor, or it does not match the incoming
+				// message encoding; attempt to find a registered compressor that does.
+				as.dc = nil
+				as.decomp = encoding.GetCompressor(ct)
+			}
+		} else {
+			// No compression is used; disable our decompressor.
+			as.dc = nil
+		}
+		// Only initialize this state once per stream.
+		as.decompSet = true
+	}
+	err = recv(as.p, as.codec, as.s, as.dc, m, *as.callInfo.maxReceiveMessageSize, nil, as.decomp)
+	if err != nil {
+		if err == io.EOF {
+			if statusErr := as.s.Status().Err(); statusErr != nil {
+				return statusErr
+			}
+			return io.EOF // indicates successful end of stream.
+		}
+		return toRPCErr(err)
+	}
+
+	if channelz.IsOn() {
+		as.t.IncrMsgRecv()
+	}
+	if as.desc.ServerStreams {
+		// Subsequent messages should be received by subsequent RecvMsg calls.
+		return nil
+	}
+
+	// Special handling for non-server-stream rpcs.
+	// This recv expects EOF or errors, so we don't collect inPayload.
+	err = recv(as.p, as.codec, as.s, as.dc, m, *as.callInfo.maxReceiveMessageSize, nil, as.decomp)
+	if err == nil {
+		return toRPCErr(errors.New("grpc: client streaming protocol violation: get <nil>, want <EOF>"))
+	}
+	if err == io.EOF {
+		return as.s.Status().Err() // non-server streaming Recv returns nil on success
+	}
+	return toRPCErr(err)
+}
+
+func (as *addrConnStream) finish(err error) {
+	as.mu.Lock()
+	if as.finished {
+		as.mu.Unlock()
+		return
+	}
+	as.finished = true
+	if err == io.EOF {
+		// Ending a stream with EOF indicates a success.
+		err = nil
+	}
+	if as.s != nil {
+		as.t.CloseStream(as.s, err)
+	}
+
+	if err != nil {
+		as.ac.incrCallsFailed()
+	} else {
+		as.ac.incrCallsSucceeded()
+	}
+	as.cancel()
+	as.mu.Unlock()
+}
+
 // ServerStream defines the server-side behavior of a streaming RPC.
 //
 // All errors returned from ServerStream methods are compatible with the
@@ -906,6 +1337,15 @@ type serverStream struct {
 
 	statsHandler stats.Handler
 
+	binlog *binarylog.MethodLogger
+	// serverHeaderBinlogged indicates whether server header has been logged. It
+	// will happen when one of the following two happens: stream.SendHeader(),
+	// stream.Send().
+	//
+	// It's only checked in send and sendHeader, doesn't need to be
+	// synchronized.
+	serverHeaderBinlogged bool
+
 	mu sync.Mutex // protects trInfo.tr after the service handler runs.
 }
 
@@ -921,7 +1361,15 @@ func (ss *serverStream) SetHeader(md metadata.MD) error {
 }
 
 func (ss *serverStream) SendHeader(md metadata.MD) error {
-	return ss.t.WriteHeader(ss.s, md)
+	err := ss.t.WriteHeader(ss.s, md)
+	if ss.binlog != nil && !ss.serverHeaderBinlogged {
+		h, _ := ss.s.Header()
+		ss.binlog.Log(&binarylog.ServerHeader{
+			Header: h,
+		})
+		ss.serverHeaderBinlogged = true
+	}
+	return err
 }
 
 func (ss *serverStream) SetTrailer(md metadata.MD) {
@@ -948,20 +1396,24 @@ func (ss *serverStream) SendMsg(m interface{}) (err error) {
 		if err != nil && err != io.EOF {
 			st, _ := status.FromError(toRPCErr(err))
 			ss.t.WriteStatus(ss.s, st)
+			// Non-user specified status was sent out. This should be an error
+			// case (as a server side Cancel maybe).
+			//
+			// This is not handled specifically now. User will return a final
+			// status from the service handler, we will log that error instead.
+			// This behavior is similar to an interceptor.
 		}
 		if channelz.IsOn() && err == nil {
 			ss.t.IncrMsgSent()
 		}
 	}()
-	data, err := encode(ss.codec, m)
-	if err != nil {
-		return err
-	}
-	compData, err := compress(data, ss.cp, ss.comp)
+
+	// load hdr, payload, data
+	hdr, payload, data, err := prepareMsg(m, ss.codec, ss.cp, ss.comp)
 	if err != nil {
 		return err
 	}
-	hdr, payload := msgHeader(data, compData)
+
 	// TODO(dfawley): should we be checking len(data) instead?
 	if len(payload) > ss.maxSendMessageSize {
 		return status.Errorf(codes.ResourceExhausted, "trying to send message larger than max (%d vs. %d)", len(payload), ss.maxSendMessageSize)
@@ -969,6 +1421,18 @@ func (ss *serverStream) SendMsg(m interface{}) (err error) {
 	if err := ss.t.Write(ss.s, hdr, payload, &transport.Options{Last: false}); err != nil {
 		return toRPCErr(err)
 	}
+	if ss.binlog != nil {
+		if !ss.serverHeaderBinlogged {
+			h, _ := ss.s.Header()
+			ss.binlog.Log(&binarylog.ServerHeader{
+				Header: h,
+			})
+			ss.serverHeaderBinlogged = true
+		}
+		ss.binlog.Log(&binarylog.ServerMessage{
+			Message: data,
+		})
+	}
 	if ss.statsHandler != nil {
 		ss.statsHandler.HandleRPC(ss.s.Context(), outPayload(false, m, data, payload, time.Now()))
 	}
@@ -992,17 +1456,26 @@ func (ss *serverStream) RecvMsg(m interface{}) (err error) {
 		if err != nil && err != io.EOF {
 			st, _ := status.FromError(toRPCErr(err))
 			ss.t.WriteStatus(ss.s, st)
+			// Non-user specified status was sent out. This should be an error
+			// case (as a server side Cancel maybe).
+			//
+			// This is not handled specifically now. User will return a final
+			// status from the service handler, we will log that error instead.
+			// This behavior is similar to an interceptor.
 		}
 		if channelz.IsOn() && err == nil {
 			ss.t.IncrMsgRecv()
 		}
 	}()
-	var inPayload *stats.InPayload
-	if ss.statsHandler != nil {
-		inPayload = &stats.InPayload{}
+	var payInfo *payloadInfo
+	if ss.statsHandler != nil || ss.binlog != nil {
+		payInfo = &payloadInfo{}
 	}
-	if err := recv(ss.p, ss.codec, ss.s, ss.dc, m, ss.maxReceiveMessageSize, inPayload, ss.decomp); err != nil {
+	if err := recv(ss.p, ss.codec, ss.s, ss.dc, m, ss.maxReceiveMessageSize, payInfo, ss.decomp); err != nil {
 		if err == io.EOF {
+			if ss.binlog != nil {
+				ss.binlog.Log(&binarylog.ClientHalfClose{})
+			}
 			return err
 		}
 		if err == io.ErrUnexpectedEOF {
@@ -1010,8 +1483,20 @@ func (ss *serverStream) RecvMsg(m interface{}) (err error) {
 		}
 		return toRPCErr(err)
 	}
-	if inPayload != nil {
-		ss.statsHandler.HandleRPC(ss.s.Context(), inPayload)
+	if ss.statsHandler != nil {
+		ss.statsHandler.HandleRPC(ss.s.Context(), &stats.InPayload{
+			RecvTime: time.Now(),
+			Payload:  m,
+			// TODO truncate large payload.
+			Data:       payInfo.uncompressedBytes,
+			WireLength: payInfo.wireLength,
+			Length:     len(payInfo.uncompressedBytes),
+		})
+	}
+	if ss.binlog != nil {
+		ss.binlog.Log(&binarylog.ClientMessage{
+			Message: payInfo.uncompressedBytes,
+		})
 	}
 	return nil
 }
@@ -1021,3 +1506,24 @@ func (ss *serverStream) RecvMsg(m interface{}) (err error) {
 func MethodFromServerStream(stream ServerStream) (string, bool) {
 	return Method(stream.Context())
 }
+
+// prepareMsg returns the hdr, payload and data
+// using the compressors passed or using the
+// passed preparedmsg
+func prepareMsg(m interface{}, codec baseCodec, cp Compressor, comp encoding.Compressor) (hdr, payload, data []byte, err error) {
+	if preparedMsg, ok := m.(*PreparedMsg); ok {
+		return preparedMsg.hdr, preparedMsg.payload, preparedMsg.encodedData, nil
+	}
+	// The input interface is not a prepared msg.
+	// Marshal and Compress the data at this point
+	data, err = encode(codec, m)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	compData, err := compress(data, cp, comp)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	hdr, payload = msgHeader(data, compData)
+	return hdr, payload, data, nil
+}
diff --git a/vendor/google.golang.org/grpc/tap/tap.go b/vendor/google.golang.org/grpc/tap/tap.go
index 22b8fb50..584360f6 100644
--- a/vendor/google.golang.org/grpc/tap/tap.go
+++ b/vendor/google.golang.org/grpc/tap/tap.go
@@ -21,7 +21,7 @@
 package tap
 
 import (
-	"golang.org/x/net/context"
+	"context"
 )
 
 // Info defines the relevant information needed by the handles.
diff --git a/vendor/google.golang.org/grpc/trace.go b/vendor/google.golang.org/grpc/trace.go
index c1c96ded..0a57b999 100644
--- a/vendor/google.golang.org/grpc/trace.go
+++ b/vendor/google.golang.org/grpc/trace.go
@@ -24,6 +24,7 @@ import (
 	"io"
 	"net"
 	"strings"
+	"sync"
 	"time"
 
 	"golang.org/x/net/trace"
@@ -53,13 +54,25 @@ type traceInfo struct {
 }
 
 // firstLine is the first line of an RPC trace.
+// It may be mutated after construction; remoteAddr specifically may change
+// during client-side use.
 type firstLine struct {
+	mu         sync.Mutex
 	client     bool // whether this is a client (outgoing) RPC
 	remoteAddr net.Addr
 	deadline   time.Duration // may be zero
 }
 
+func (f *firstLine) SetRemoteAddr(addr net.Addr) {
+	f.mu.Lock()
+	f.remoteAddr = addr
+	f.mu.Unlock()
+}
+
 func (f *firstLine) String() string {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
 	var line bytes.Buffer
 	io.WriteString(&line, "RPC: ")
 	if f.client {
diff --git a/vendor/google.golang.org/grpc/version.go b/vendor/google.golang.org/grpc/version.go
index d668a424..5411a73a 100644
--- a/vendor/google.golang.org/grpc/version.go
+++ b/vendor/google.golang.org/grpc/version.go
@@ -19,4 +19,4 @@
 package grpc
 
 // Version is the current grpc version.
-const Version = "1.14.0"
+const Version = "1.23.0"
diff --git a/vendor/google.golang.org/grpc/vet.sh b/vendor/google.golang.org/grpc/vet.sh
index 44a310e5..661e1e1d 100755
--- a/vendor/google.golang.org/grpc/vet.sh
+++ b/vendor/google.golang.org/grpc/vet.sh
@@ -13,19 +13,43 @@ die() {
   exit 1
 }
 
-PATH="$GOPATH/bin:$GOROOT/bin:$PATH"
-
-if [ "$1" = "-install" ]; then
-  go get -d \
-    google.golang.org/grpc/...
-  go get -u \
-    github.com/golang/lint/golint \
-    golang.org/x/tools/cmd/goimports \
-    honnef.co/go/tools/cmd/staticcheck \
-    github.com/client9/misspell/cmd/misspell \
-    github.com/golang/protobuf/protoc-gen-go
-  if [[ -z "$VET_SKIP_PROTO" ]]; then
-    if [[ "$TRAVIS" = "true" ]]; then
+fail_on_output() {
+  tee /dev/stderr | (! read)
+}
+
+# Check to make sure it's safe to modify the user's git repo.
+git status --porcelain | fail_on_output
+
+# Undo any edits made by this script.
+cleanup() {
+  git reset --hard HEAD
+}
+trap cleanup EXIT
+
+PATH="${GOPATH}/bin:${GOROOT}/bin:${PATH}"
+
+if [[ "$1" = "-install" ]]; then
+  # Check for module support
+  if go help mod >& /dev/null; then
+    go install \
+      golang.org/x/lint/golint \
+      golang.org/x/tools/cmd/goimports \
+      honnef.co/go/tools/cmd/staticcheck \
+      github.com/client9/misspell/cmd/misspell \
+      github.com/golang/protobuf/protoc-gen-go
+  else
+    # Ye olde `go get` incantation.
+    # Note: this gets the latest version of all tools (vs. the pinned versions
+    # with Go modules).
+    go get -u \
+      golang.org/x/lint/golint \
+      golang.org/x/tools/cmd/goimports \
+      honnef.co/go/tools/cmd/staticcheck \
+      github.com/client9/misspell/cmd/misspell \
+      github.com/golang/protobuf/protoc-gen-go
+  fi
+  if [[ -z "${VET_SKIP_PROTO}" ]]; then
+    if [[ "${TRAVIS}" = "true" ]]; then
       PROTOBUF_VERSION=3.3.0
       PROTOC_FILENAME=protoc-${PROTOBUF_VERSION}-linux-x86_64.zip
       pushd /home/travis
@@ -42,48 +66,69 @@ elif [[ "$#" -ne 0 ]]; then
   die "Unknown argument(s): $*"
 fi
 
-# TODO: Remove this check and the mangling below once "context" is imported
-# directly.
-if git status --porcelain | read; then
-  die "Uncommitted or untracked files found; commit changes first"
-fi
+# - Ensure all source files contain a copyright message.
+git ls-files "*.go" | xargs grep -L "\(Copyright [0-9]\{4,\} gRPC authors\)\|DO NOT EDIT" 2>&1 | fail_on_output
 
-git ls-files "*.go" | xargs grep -L "\(Copyright [0-9]\{4,\} gRPC authors\)\|DO NOT EDIT" 2>&1 | tee /dev/stderr | (! read)
-git ls-files "*.go" | xargs grep -l '"unsafe"' 2>&1 | (! grep -v '_test.go') | tee /dev/stderr | (! read)
-git ls-files "*.go" | xargs grep -l '"math/rand"' 2>&1 | (! grep -v '^examples\|^stress\|grpcrand') | tee /dev/stderr | (! read)
-gofmt -s -d -l . 2>&1 | tee /dev/stderr | (! read)
-goimports -l . 2>&1 | tee /dev/stderr | (! read)
-golint ./... 2>&1 | (grep -vE "(_mock|\.pb)\.go:" || true) | tee /dev/stderr | (! read)
+# - Make sure all tests in grpc and grpc/test use leakcheck via Teardown.
+(! grep 'func Test[^(]' *_test.go)
+(! grep 'func Test[^(]' test/*.go)
 
-# Undo any edits made by this script.
-cleanup() {
-  git reset --hard HEAD
-}
-trap cleanup EXIT
+# - Do not import math/rand for real library code.  Use internal/grpcrand for
+#   thread safety.
+git ls-files "*.go" | xargs grep -l '"math/rand"' 2>&1 | (! grep -v '^examples\|^stress\|grpcrand\|wrr_test')
+
+# - Ensure all ptypes proto packages are renamed when importing.
+git ls-files "*.go" | (! xargs grep "\(import \|^\s*\)\"github.com/golang/protobuf/ptypes/")
+
+# - Check imports that are illegal in appengine (until Go 1.11).
+# TODO: Remove when we drop Go 1.10 support
+go list -f {{.Dir}} ./... | xargs go run test/go_vet/vet.go
+
+# - gofmt, goimports, golint (with exceptions for generated code), go vet.
+gofmt -s -d -l . 2>&1 | fail_on_output
+goimports -l . 2>&1 | (! grep -vE "(_mock|\.pb)\.go:") | fail_on_output
+golint ./... 2>&1 | (! grep -vE "(_mock|\.pb)\.go:")
+go vet -all .
+
+# - Check that generated proto files are up to date.
+if [[ -z "${VET_SKIP_PROTO}" ]]; then
+  PATH="/home/travis/bin:${PATH}" make proto && \
+    git status --porcelain 2>&1 | fail_on_output || \
+    (git status; git --no-pager diff; exit 1)
+fi
 
-# Rewrite golang.org/x/net/context -> context imports (see grpc/grpc-go#1484).
-# TODO: Remove this mangling once "context" is imported directly (grpc/grpc-go#711).
-git ls-files "*.go" | xargs sed -i 's:"golang.org/x/net/context":"context":'
-set +o pipefail
-# TODO: Stop filtering pb.go files once golang/protobuf#214 is fixed.
-go tool vet -all . 2>&1 | grep -vE '(clientconn|transport\/transport_test).go:.*cancel (function|var)' | grep -vF '.pb.go:' | tee /dev/stderr | (! read)
-set -o pipefail
-git reset --hard HEAD
-
-if [[ -z "$VET_SKIP_PROTO" ]]; then
-  PATH="/home/travis/bin:$PATH" make proto && \
-    git status --porcelain 2>&1 | (! read) || \
+# - Check that our module is tidy.
+if go help mod >& /dev/null; then
+  go mod tidy && \
+    git status --porcelain 2>&1 | fail_on_output || \
     (git status; git --no-pager diff; exit 1)
 fi
 
-# TODO(menghanl): fix errors in transport_test.
-staticcheck -ignore '
-google.golang.org/grpc/internal/transport/transport_test.go:SA2002
+# - Collection of static analysis checks
+# TODO(dfawley): don't use deprecated functions in examples.
+staticcheck -go 1.9 -checks 'inherit,-ST1015' -ignore '
+google.golang.org/grpc/balancer.go:SA1019
+google.golang.org/grpc/balancer/grpclb/grpclb_remote_balancer.go:SA1019
+google.golang.org/grpc/balancer/roundrobin/roundrobin_test.go:SA1019
+google.golang.org/grpc/xds/internal/balancer/edsbalancer/balancergroup.go:SA1019
+google.golang.org/grpc/xds/internal/balancer/xds.go:SA1019
+google.golang.org/grpc/xds/internal/balancer/xds_client.go:SA1019
+google.golang.org/grpc/balancer_conn_wrappers.go:SA1019
+google.golang.org/grpc/balancer_test.go:SA1019
 google.golang.org/grpc/benchmark/benchmain/main.go:SA1019
+google.golang.org/grpc/benchmark/worker/benchmark_client.go:SA1019
+google.golang.org/grpc/clientconn.go:S1024
+google.golang.org/grpc/clientconn_state_transition_test.go:SA1019
+google.golang.org/grpc/clientconn_test.go:SA1019
+google.golang.org/grpc/examples/features/debugging/client/main.go:SA1019
+google.golang.org/grpc/examples/features/load_balancing/client/main.go:SA1019
+google.golang.org/grpc/internal/transport/handler_server.go:SA1019
+google.golang.org/grpc/internal/transport/handler_server_test.go:SA1019
+google.golang.org/grpc/resolver/dns/dns_resolver.go:SA1019
 google.golang.org/grpc/stats/stats_test.go:SA1019
+google.golang.org/grpc/test/balancer_test.go:SA1019
+google.golang.org/grpc/test/channelz_test.go:SA1019
 google.golang.org/grpc/test/end2end_test.go:SA1019
-google.golang.org/grpc/balancer_test.go:SA1019
-google.golang.org/grpc/balancer.go:SA1019
-google.golang.org/grpc/clientconn_test.go:SA1019
+google.golang.org/grpc/test/healthcheck_test.go:SA1019
 ' ./...
 misspell -error .