net/http/httputil: run the ReverseProxy.ModifyResponse hook for upgrades
Fixes #29627
Change-Id: I08a5b45151a11b5a4f3b5a2d984c0322cf904697
Reviewed-on: https://go-review.googlesource.com/c/157098
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/src/net/http/httputil/reverseproxy.go b/src/net/http/httputil/reverseproxy.go
index 1c9feb7..4e10bf3 100644
--- a/src/net/http/httputil/reverseproxy.go
+++ b/src/net/http/httputil/reverseproxy.go
@@ -171,6 +171,20 @@
return p.defaultErrorHandler
}
+// modifyResponse conditionally runs the optional ModifyResponse hook
+// and reports whether the request should proceed.
+func (p *ReverseProxy) modifyResponse(rw http.ResponseWriter, res *http.Response, req *http.Request) bool {
+ if p.ModifyResponse == nil {
+ return true
+ }
+ if err := p.ModifyResponse(res); err != nil {
+ res.Body.Close()
+ p.getErrorHandler()(rw, req, err)
+ return false
+ }
+ return true
+}
+
func (p *ReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
transport := p.Transport
if transport == nil {
@@ -250,6 +264,9 @@
// Deal with 101 Switching Protocols responses: (WebSocket, h2c, etc)
if res.StatusCode == http.StatusSwitchingProtocols {
+ if !p.modifyResponse(rw, res, outreq) {
+ return
+ }
p.handleUpgradeResponse(rw, outreq, res)
return
}
@@ -260,12 +277,8 @@
res.Header.Del(h)
}
- if p.ModifyResponse != nil {
- if err := p.ModifyResponse(res); err != nil {
- res.Body.Close()
- p.getErrorHandler()(rw, outreq, err)
- return
- }
+ if !p.modifyResponse(rw, res, outreq) {
+ return
}
copyHeader(rw.Header(), res.Header)
diff --git a/src/net/http/httputil/reverseproxy_test.go b/src/net/http/httputil/reverseproxy_test.go
index bda569a..5edefa0 100644
--- a/src/net/http/httputil/reverseproxy_test.go
+++ b/src/net/http/httputil/reverseproxy_test.go
@@ -1012,6 +1012,10 @@
backURL, _ := url.Parse(backendServer.URL)
rproxy := NewSingleHostReverseProxy(backURL)
rproxy.ErrorLog = log.New(ioutil.Discard, "", 0) // quiet for tests
+ rproxy.ModifyResponse = func(res *http.Response) error {
+ res.Header.Add("X-Modified", "true")
+ return nil
+ }
handler := http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
rw.Header().Set("X-Header", "X-Value")
@@ -1049,6 +1053,10 @@
}
defer rwc.Close()
+ if got, want := res.Header.Get("X-Modified"), "true"; got != want {
+ t.Errorf("response X-Modified header = %q; want %q", got, want)
+ }
+
io.WriteString(rwc, "Hello\n")
bs := bufio.NewScanner(rwc)
if !bs.Scan() {
