From e558f470b7914de74cfb82c27905516874ce04ef Mon Sep 17 00:00:00 2001
From: Brian Woods <me@brian.biz>
Date: Sun, 31 Mar 2019 08:04:33 -0700
Subject: [PATCH 1/2] adds compression to json-rpc endpoint

---
 rpc/gzip.go | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 rpc/http.go |  1 +
 2 files changed, 51 insertions(+)
 create mode 100644 rpc/gzip.go

diff --git a/rpc/gzip.go b/rpc/gzip.go
new file mode 100644
index 000000000000..17f8fc61498e
--- /dev/null
+++ b/rpc/gzip.go
@@ -0,0 +1,50 @@
+package rpc
+
+import (
+	"compress/gzip"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"strings"
+	"sync"
+)
+
+var gzPool = sync.Pool{
+	New: func() interface{} {
+		w := gzip.NewWriter(ioutil.Discard)
+		return w
+	},
+}
+
+type gzipResponseWriter struct {
+	io.Writer
+	http.ResponseWriter
+}
+
+func (w *gzipResponseWriter) WriteHeader(status int) {
+	w.Header().Del("Content-Length")
+	w.ResponseWriter.WriteHeader(status)
+}
+
+func (w *gzipResponseWriter) Write(b []byte) (int, error) {
+	return w.Writer.Write(b)
+}
+
+func Gzip(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
+			next.ServeHTTP(w, r)
+			return
+		}
+
+		w.Header().Set("Content-Encoding", "gzip")
+
+		gz := gzPool.Get().(*gzip.Writer)
+		defer gzPool.Put(gz)
+
+		gz.Reset(w)
+		defer gz.Close()
+
+		next.ServeHTTP(&gzipResponseWriter{ResponseWriter: w, Writer: gz}, r)
+	})
+}
diff --git a/rpc/http.go b/rpc/http.go
index 518b3b874f15..9067b9726e6f 100644
--- a/rpc/http.go
+++ b/rpc/http.go
@@ -216,6 +216,7 @@ func NewHTTPServer(cors []string, vhosts []string, timeouts HTTPTimeouts, srv ht
 	// Wrap the CORS-handler within a host-handler
 	handler := newCorsHandler(srv, cors)
 	handler = newVHostHandler(vhosts, handler)
+	handler = Gzip(handler)
 
 	// Make sure timeout values are meaningful
 	if timeouts.ReadTimeout < time.Second {

From 260de46157d81a513af0bc5e42ca75cd2046b914 Mon Sep 17 00:00:00 2001
From: Sjon Hortensius <sjon@hortensius.net>
Date: Thu, 22 Aug 2019 14:50:36 +0200
Subject: [PATCH 2/2] Ref #19357, fix two nitpicks, add copyright header and
 rename constructor

---
 rpc/gzip.go | 18 +++++++++++++++++-
 rpc/http.go |  2 +-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/rpc/gzip.go b/rpc/gzip.go
index 17f8fc61498e..a14fd09d5407 100644
--- a/rpc/gzip.go
+++ b/rpc/gzip.go
@@ -1,3 +1,19 @@
+// Copyright 2019 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
 package rpc
 
 import (
@@ -30,7 +46,7 @@ func (w *gzipResponseWriter) Write(b []byte) (int, error) {
 	return w.Writer.Write(b)
 }
 
-func Gzip(next http.Handler) http.Handler {
+func newGzipHandler(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
 			next.ServeHTTP(w, r)
diff --git a/rpc/http.go b/rpc/http.go
index 9067b9726e6f..5a041be9656f 100644
--- a/rpc/http.go
+++ b/rpc/http.go
@@ -216,7 +216,7 @@ func NewHTTPServer(cors []string, vhosts []string, timeouts HTTPTimeouts, srv ht
 	// Wrap the CORS-handler within a host-handler
 	handler := newCorsHandler(srv, cors)
 	handler = newVHostHandler(vhosts, handler)
-	handler = Gzip(handler)
+	handler = newGzipHandler(handler)
 
 	// Make sure timeout values are meaningful
 	if timeouts.ReadTimeout < time.Second {