http: ignore Transfer-Encoding on HEAD responses
Amazon S3 sends Transfer-Encoding "chunked"
on its 404 responses to HEAD requests for
missing objects.
We weren't ignoring the Transfer-Encoding
and were thus interpretting the subsequent
response headers as a chunk header from the
previous responses body (but a HEAD response
can't have a body)
R=rsc, adg
CC=golang-dev
https://golang.org/cl/4346050
diff --git a/src/pkg/http/response_test.go b/src/pkg/http/response_test.go
index bf63ccb..ef67fdd 100644
--- a/src/pkg/http/response_test.go
+++ b/src/pkg/http/response_test.go
@@ -164,6 +164,28 @@
"Body here\n",
},
+ // Chunked response in response to a HEAD request (the "chunked" should
+ // be ignored, as HEAD responses never have bodies)
+ {
+ "HTTP/1.0 200 OK\r\n" +
+ "Transfer-Encoding: chunked\r\n" +
+ "\r\n",
+
+ Response{
+ Status: "200 OK",
+ StatusCode: 200,
+ Proto: "HTTP/1.0",
+ ProtoMajor: 1,
+ ProtoMinor: 0,
+ RequestMethod: "HEAD",
+ Header: Header{},
+ Close: true,
+ ContentLength: 0,
+ },
+
+ "",
+ },
+
// Status line without a Reason-Phrase, but trailing space.
// (permitted by RFC 2616)
{
diff --git a/src/pkg/http/transfer.go b/src/pkg/http/transfer.go
index 996e289..41614f1 100644
--- a/src/pkg/http/transfer.go
+++ b/src/pkg/http/transfer.go
@@ -215,7 +215,7 @@
}
// Transfer encoding, content length
- t.TransferEncoding, err = fixTransferEncoding(t.Header)
+ t.TransferEncoding, err = fixTransferEncoding(t.RequestMethod, t.Header)
if err != nil {
return err
}
@@ -289,13 +289,20 @@
func chunked(te []string) bool { return len(te) > 0 && te[0] == "chunked" }
// Sanitize transfer encoding
-func fixTransferEncoding(header Header) ([]string, os.Error) {
+func fixTransferEncoding(requestMethod string, header Header) ([]string, os.Error) {
raw, present := header["Transfer-Encoding"]
if !present {
return nil, nil
}
header["Transfer-Encoding"] = nil, false
+
+ // Head responses have no bodies, so the transfer encoding
+ // should be ignored.
+ if requestMethod == "HEAD" {
+ return nil, nil
+ }
+
encodings := strings.Split(raw[0], ",", -1)
te := make([]string, 0, len(encodings))
// TODO: Even though we only support "identity" and "chunked"
diff --git a/src/pkg/http/transport_test.go b/src/pkg/http/transport_test.go
index 8a77a48..e46f830c 100644
--- a/src/pkg/http/transport_test.go
+++ b/src/pkg/http/transport_test.go
@@ -296,6 +296,35 @@
}
}
+// TestTransportHeadChunkedResponse verifies that we ignore chunked transfer-encoding
+// on responses to HEAD requests.
+func TestTransportHeadChunkedResponse(t *testing.T) {
+ ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+ if r.Method != "HEAD" {
+ panic("expected HEAD; got " + r.Method)
+ }
+ w.Header().Set("Transfer-Encoding", "chunked") // client should ignore
+ w.Header().Set("x-client-ipport", r.RemoteAddr)
+ w.WriteHeader(200)
+ }))
+ defer ts.Close()
+
+ tr := &Transport{DisableKeepAlives: false}
+ c := &Client{Transport: tr}
+
+ res1, err := c.Head(ts.URL)
+ if err != nil {
+ t.Fatalf("request 1 error: %v", err)
+ }
+ res2, err := c.Head(ts.URL)
+ if err != nil {
+ t.Fatalf("request 2 error: %v", err)
+ }
+ if v1, v2 := res1.Header.Get("x-client-ipport"), res2.Header.Get("x-client-ipport"); v1 != v2 {
+ t.Errorf("ip/ports differed between head requests: %q vs %q", v1, v2)
+ }
+}
+
func TestTransportNilURL(t *testing.T) {
ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
fmt.Fprintf(w, "Hi")
