Remove unused frontend scheduler code

CHANGELOG.md

@@ -8,6 +8,7 @@
   compactor.compaction.flush_size_bytes. [#1696](https://github.com/grafana/tempo/pull/1696) (@joe-elliott)
 * [CHANGE] Return 200 instead of 206 when blocks failed is < tolerate_failed_blocks. [#1725](https://github.com/grafana/tempo/pull/1725) (@joe-elliott)
 * [CHANGE] Update Go to 1.19 [#1665](https://github.com/grafana/tempo/pull/1665) (@ie-pham)
+* [CHANGE] Remove unsued scheduler frontend code [#1734](https://github.com/grafana/tempo/pull/1734) (@mapno)
 * [FEATURE] Add capability to configure the used S3 Storage Class [#1697](https://github.com/grafana/tempo/pull/1714) (@amitsetty)
 * [ENHANCEMENT] cache: expose username and sentinel_username redis configuration options for ACL-based Redis Auth support [#1708](https://github.com/grafana/tempo/pull/1708) (@jsievenpiper)
 * [ENHANCEMENT] metrics-generator: expose span size as a metric [#1662](https://github.com/grafana/tempo/pull/1662) (@ie-pham)

Makefile

@@ -11,7 +11,7 @@ GOPATH := $(shell go env GOPATH)
 GORELEASER := $(GOPATH)/bin/goreleaser
 
 # Build Images
-DOCKER_PROTOBUF_IMAGE ?= otel/build-protobuf:0.2.1
+DOCKER_PROTOBUF_IMAGE ?= otel/build-protobuf:0.14.0
 FLATBUFFERS_IMAGE ?= neomantra/flatbuffers
 LOKI_BUILD_IMAGE ?= grafana/loki-build-image:0.21.0
 DOCS_IMAGE ?= grafana/docs-base:latest
@@ -184,7 +184,6 @@ gen-proto:
 	$(call PROTO_GEN,$(PROTO_INTERMEDIATE_DIR)/trace/v1/trace.proto,./pkg/tempopb/)
 	$(call PROTO_GEN,pkg/tempopb/tempo.proto,./)
 	$(call PROTO_GEN_WITH_VENDOR,modules/frontend/v1/frontendv1pb/frontend.proto,./)
-	$(call PROTO_GEN_WITH_VENDOR,modules/frontend/v2/frontendv2pb/frontend.proto,./)
 
 	rm -rf $(PROTO_INTERMEDIATE_DIR)
 

cmd/tempo/app/modules.go

@@ -216,9 +216,9 @@ func (t *App) initQuerier() (services.Service, error) {
 }
 
 func (t *App) initQueryFrontend() (services.Service, error) {
-	// cortexTripper is a bridge between http and httpgrpc. it does the job of passing data to the cortex
-	// frontend code
-	cortexTripper, v1, _, err := frontend.InitFrontend(t.cfg.Frontend.Config, frontend.CortexNoQuerierLimits{}, 0, log.Logger, prometheus.DefaultRegisterer)
+	// cortexTripper is a bridge between http and httpgrpc.
+	// It does the job of passing data to the cortex frontend code.
+	cortexTripper, v1, err := frontend.InitFrontend(t.cfg.Frontend.Config, frontend.CortexNoQuerierLimits{}, log.Logger, prometheus.DefaultRegisterer)
 	if err != nil {
 		return nil, err
 	}

modules/frontend/config.go

@@ -7,37 +7,31 @@ import (
 	"net/http"
 
 	"github.com/go-kit/log"
-	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
 
 	"github.com/grafana/tempo/modules/frontend/transport"
 	v1 "github.com/grafana/tempo/modules/frontend/v1"
-	v2 "github.com/grafana/tempo/modules/frontend/v2"
 	"github.com/grafana/tempo/pkg/usagestats"
-	"github.com/grafana/tempo/pkg/util"
 )
 
 var (
-	statWorkerConcurrency = usagestats.NewInt("frontend_worker_concurrency")
-	statVersion           = usagestats.NewString("frontend_version")
+	statVersion = usagestats.NewString("frontend_version")
 )
 
 type Config struct {
-	Config               CombinedFrontendConfig `yaml:",inline"`
-	MaxRetries           int                    `yaml:"max_retries,omitempty"`
-	QueryShards          int                    `yaml:"query_shards,omitempty"`
-	TolerateFailedBlocks int                    `yaml:"tolerate_failed_blocks,omitempty"`
-	Search               SearchConfig           `yaml:"search"`
+	Config               v1.Config    `yaml:",inline"`
+	MaxRetries           int          `yaml:"max_retries,omitempty"`
+	QueryShards          int          `yaml:"query_shards,omitempty"`
+	TolerateFailedBlocks int          `yaml:"tolerate_failed_blocks,omitempty"`
+	Search               SearchConfig `yaml:"search"`
 }
 
 type SearchConfig struct {
 	Sharder SearchSharderConfig `yaml:",inline"`
 }
 
-func (cfg *Config) RegisterFlagsAndApplyDefaults(prefix string, f *flag.FlagSet) {
-	cfg.Config.DownstreamURL = ""
-	cfg.Config.Handler.LogQueriesLongerThan = 0
-	cfg.Config.FrontendV1.MaxOutstandingPerTenant = 100
+func (cfg *Config) RegisterFlagsAndApplyDefaults(string, *flag.FlagSet) {
+	cfg.Config.MaxOutstandingPerTenant = 100
 	cfg.MaxRetries = 2
 	cfg.QueryShards = 20
 	cfg.TolerateFailedBlocks = 0
@@ -58,66 +52,19 @@ type CortexNoQuerierLimits struct{}
 
 var _ v1.Limits = (*CortexNoQuerierLimits)(nil)
 
-func (CortexNoQuerierLimits) MaxQueriersPerUser(user string) int { return 0 }
+func (CortexNoQuerierLimits) MaxQueriersPerUser(string) int { return 0 }
 
-// This struct combines several configuration options together to preserve backwards compatibility.
-type CombinedFrontendConfig struct {
-	Handler    transport.HandlerConfig `yaml:",inline"`
-	FrontendV1 v1.Config               `yaml:",inline"`
-	FrontendV2 v2.Config               `yaml:",inline"`
-
-	DownstreamURL string `yaml:"downstream_url"`
-}
-
-func (cfg *CombinedFrontendConfig) RegisterFlags(f *flag.FlagSet) {
-	cfg.Handler.RegisterFlags(f)
-	cfg.FrontendV1.RegisterFlags(f)
-	cfg.FrontendV2.RegisterFlags(f)
-
-	f.StringVar(&cfg.DownstreamURL, "frontend.downstream-url", "", "URL of downstream Prometheus.")
-}
-
-// InitFrontend initializes frontend (either V1 -- without scheduler, or V2 -- with scheduler) or no frontend at
-// all if downstream Prometheus URL is used instead.
+// InitFrontend initializes V1 frontend
 //
 // Returned RoundTripper can be wrapped in more round-tripper middlewares, and then eventually registered
 // into HTTP server using the Handler from this package. Returned RoundTripper is always non-nil
 // (if there are no errors), and it uses the returned frontend (if any).
-func InitFrontend(cfg CombinedFrontendConfig, limits v1.Limits, grpcListenPort int, log log.Logger, reg prometheus.Registerer) (http.RoundTripper, *v1.Frontend, *v2.Frontend, error) {
-	switch {
-	case cfg.DownstreamURL != "":
-		// If the user has specified a downstream Prometheus, then we should use that.
-		rt, err := NewDownstreamRoundTripper(cfg.DownstreamURL, http.DefaultTransport)
-		return rt, nil, nil, err
-
-	case cfg.FrontendV2.SchedulerAddress != "":
-		statVersion.Set("v2")
-		statWorkerConcurrency.Set(int64(cfg.FrontendV2.WorkerConcurrency))
-
-		// If query-scheduler address is configured, use Frontend.
-		if cfg.FrontendV2.Addr == "" {
-			addr, err := util.GetFirstAddressOf(cfg.FrontendV2.InfNames)
-			if err != nil {
-				return nil, nil, nil, errors.Wrap(err, "failed to get frontend address")
-			}
-
-			cfg.FrontendV2.Addr = addr
-		}
-
-		if cfg.FrontendV2.Port == 0 {
-			cfg.FrontendV2.Port = grpcListenPort
-		}
-
-		fr, err := v2.NewFrontend(cfg.FrontendV2, log, reg)
-		return transport.AdaptGrpcRoundTripperToHTTPRoundTripper(fr), nil, fr, err
-
-	default:
-		statVersion.Set("v1")
-		// No scheduler = use original frontend.
-		fr, err := v1.New(cfg.FrontendV1, limits, log, reg)
-		if err != nil {
-			return nil, nil, nil, err
-		}
-		return transport.AdaptGrpcRoundTripperToHTTPRoundTripper(fr), fr, nil, nil
+func InitFrontend(cfg v1.Config, limits v1.Limits, log log.Logger, reg prometheus.Registerer) (http.RoundTripper, *v1.Frontend, error) {
+	statVersion.Set("v1")
+	// No scheduler = use original frontend.
+	fr, err := v1.New(cfg, limits, log, reg)
+	if err != nil {
+		return nil, nil, err
 	}
+	return transport.AdaptGrpcRoundTripperToHTTPRoundTripper(fr), fr, nil
 }

modules/frontend/frontend.go

@@ -11,8 +11,8 @@ import (
 
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
-	"github.com/golang/protobuf/jsonpb" //nolint:all //deprecated 
-	"github.com/golang/protobuf/proto"  //nolint:all //deprecated 
+	"github.com/golang/protobuf/jsonpb" //nolint:all //deprecated
+	"github.com/golang/protobuf/proto"  //nolint:all //deprecated
 	"github.com/opentracing/opentracing-go"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"

modules/frontend/tracebyidsharding.go

@@ -13,7 +13,7 @@ import (
 
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
-	"github.com/golang/protobuf/proto"  //nolint:all //deprecated 
+	"github.com/golang/protobuf/proto" //nolint:all //deprecated
 	"github.com/grafana/tempo/modules/querier"
 	"github.com/grafana/tempo/pkg/api"
 	"github.com/grafana/tempo/pkg/model/trace"