Description
Please answer these questions before submitting your issue. Thanks!
What version of Go are you using (go version)?
go version devel +1948b7f Wed May 31 10:28:05 2017 +0000 linux/amd64
What operating system and processor architecture are you using (go env)?
GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/tw/golib"
GORACE=""
GOROOT="/home/tw/goroot"
GOTOOLDIR="/home/tw/goroot/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build555764928=/tmp/go-build -gno-record-gcc-switches"
CXX="g++"
CGO_ENABLED="1"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config
What did you do?
package main
import (
"fmt"
"log"
"net/http"
"net/http/httptest"
"net/http/httputil"
"net/url"
)
func main() {
backendServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(http.StatusOK)
}))
defer backendServer.Close()
rpURL, err := url.Parse(backendServer.URL)
if err != nil {
log.Fatal(err)
}
frontendProxy := httptest.NewServer(httputil.NewSingleHostReverseProxy(rpURL))
defer frontendProxy.Close()
resp, err := http.Get(frontendProxy.URL)
if err != nil {
log.Fatal(err)
}
fmt.Printf("response header: %#v\n", resp.Header)
}
What did you expect to see?
Content-Type should not be set with empty content.
What did you see instead?
Content-Type is set automatically by Go http server.
response header: http.Header{"Content-Length":[]string{"0"}, "Content-Type":[]string{"text/plain; charset=utf-8"}, "Date":[]string{"Sat, 24 Jun 2017 05:18:32 GMT"}}
I suppose this patch should work:
diff --git a/src/net/http/server.go b/src/net/http/server.go
index add05c2..a48b88b 100644
--- a/src/net/http/server.go
+++ b/src/net/http/server.go
@@ -1304,7 +1304,7 @@ func (cw *chunkWriter) writeHeader(p []byte) {
if bodyAllowedForStatus(code) {
// If no content type, apply sniffing algorithm to body.
_, haveType := header["Content-Type"]
- if !haveType && !hasTE {
+ if !haveType && !hasTE && len(p) > 0 {
setHeader.contentType = DetectContentType(p)
}
} else {
Any thoughts ?