From 2788b470597719a574ffe092819401814587b074 Mon Sep 17 00:00:00 2001
From: Vishnu kannan <vishnuk@google.com>
Date: Mon, 28 Sep 2015 16:42:34 -0700
Subject: [PATCH] Avoid rewriting URLs in the proxy, if the application is
 proxy-aware.

---
 pkg/util/proxy/transport.go      | 5 ++++-
 pkg/util/proxy/transport_test.go | 8 ++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/pkg/util/proxy/transport.go b/pkg/util/proxy/transport.go
index ca88147752d..80855f46b8b 100644
--- a/pkg/util/proxy/transport.go
+++ b/pkg/util/proxy/transport.go
@@ -136,8 +136,11 @@ func (t *Transport) rewriteURL(targetURL string, sourceURL *url.URL) string {
 	url.Scheme = t.Scheme
 	url.Host = t.Host
 	origPath := url.Path
+	// Do not rewrite URL if the sourceURL already contains the necessary prefix.
+	if strings.HasPrefix(url.Path, t.PathPrepend) {
+		return url.String()
+	}
 	url.Path = path.Join(t.PathPrepend, url.Path)
-
 	if strings.HasSuffix(origPath, "/") {
 		// Add back the trailing slash, which was stripped by path.Join().
 		url.Path += "/"
diff --git a/pkg/util/proxy/transport_test.go b/pkg/util/proxy/transport_test.go
index 4f5fb01ced9..0e444f9ab5d 100644
--- a/pkg/util/proxy/transport_test.go
+++ b/pkg/util/proxy/transport_test.go
@@ -150,6 +150,14 @@ func TestProxyTransport(t *testing.T) {
 			redirectWant: "http://example.com/redirected/target/",
 			forwardedURI: "/proxy/minion/minion1:10250/redirect",
 		},
+		"source contains the redirect already": {
+			input:        `<pre><a href="kubelet.log">kubelet.log</a><a href="http://foo.com/proxy/minion/minion1:10250/google.log">google.log</a></pre>`,
+			sourceURL:    "http://foo.com/logs/log.log",
+			transport:    testTransport,
+			output:       `<pre><a href="kubelet.log">kubelet.log</a><a href="http://foo.com/proxy/minion/minion1:10250/google.log">google.log</a></pre>`,
+			contentType:  "text/html",
+			forwardedURI: "/proxy/minion/minion1:10250/logs/log.log",
+		},
 	}
 
 	testItem := func(name string, item *Item) {