From 71b3ca0817389602ae6c72619e58919243a5b532 Mon Sep 17 00:00:00 2001
From: Alexey Borzenkov <snaury@gmail.com>
Date: Wed, 13 Jun 2012 16:24:23 -0400
Subject: [PATCH] [release-branch.go1] net/http: reuse http proxy connections
 for different http requests
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««« backport d0bc02d414c7
net/http: reuse http proxy connections for different http requests

Comment on cache keys above connectMethod says "http to proxy, http
anywhere after that", however in reality target address was always
included, which prevented http requests to different target
addresses to reuse the same http proxy connection.

R=golang-dev, r, rsc, bradfitz
CC=golang-dev
https://golang.org/cl/5901064

»»»
---
 src/pkg/net/http/proxy_test.go | 30 ++++++++++++++++++++++++++++++
 src/pkg/net/http/transport.go  |  6 +++++-
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/src/pkg/net/http/proxy_test.go b/src/pkg/net/http/proxy_test.go
index 9b320b3aa5..5ecffaface 100644
--- a/src/pkg/net/http/proxy_test.go
+++ b/src/pkg/net/http/proxy_test.go
@@ -5,6 +5,7 @@
 package http
 
 import (
+	"net/url"
 	"os"
 	"testing"
 )
@@ -46,3 +47,32 @@ func TestUseProxy(t *testing.T) {
 		}
 	}
 }
+
+var cacheKeysTests = []struct {
+	proxy  string
+	scheme string
+	addr   string
+	key    string
+}{
+	{"", "http", "foo.com", "|http|foo.com"},
+	{"", "https", "foo.com", "|https|foo.com"},
+	{"http://foo.com", "http", "foo.com", "http://foo.com|http|"},
+	{"http://foo.com", "https", "foo.com", "http://foo.com|https|foo.com"},
+}
+
+func TestCacheKeys(t *testing.T) {
+	for _, tt := range cacheKeysTests {
+		var proxy *url.URL
+		if tt.proxy != "" {
+			u, err := url.Parse(tt.proxy)
+			if err != nil {
+				t.Fatal(err)
+			}
+			proxy = u
+		}
+		cm := connectMethod{proxy, tt.scheme, tt.addr}
+		if cm.String() != tt.key {
+			t.Fatalf("{%q, %q, %q} cache key %q; want %q", tt.proxy, tt.scheme, tt.addr, cm.String(), tt.key)
+		}
+	}
+}
diff --git a/src/pkg/net/http/transport.go b/src/pkg/net/http/transport.go
index 024975946e..6efe191eb0 100644
--- a/src/pkg/net/http/transport.go
+++ b/src/pkg/net/http/transport.go
@@ -450,10 +450,14 @@ type connectMethod struct {
 
 func (ck *connectMethod) String() string {
 	proxyStr := ""
+	targetAddr := ck.targetAddr
 	if ck.proxyURL != nil {
 		proxyStr = ck.proxyURL.String()
+		if ck.targetScheme == "http" {
+			targetAddr = ""
+		}
 	}
-	return strings.Join([]string{proxyStr, ck.targetScheme, ck.targetAddr}, "|")
+	return strings.Join([]string{proxyStr, ck.targetScheme, targetAddr}, "|")
 }
 
 // addr returns the first hop "host:port" to which we need to TCP connect.
-- 
2.48.1