Resync oxy with original repository

vendor/github.com/vulcand/oxy/utils/netutils.go

@@ -2,19 +2,23 @@ package utils
 
 import (
 	"bufio"
+	"fmt"
 	"io"
-	"mime"
 	"net"
 	"net/http"
 	"net/url"
+	"reflect"
+
+	log "github.com/Sirupsen/logrus"
 )
 
 // ProxyWriter helps to capture response headers and status code
 // from the ServeHTTP. It can be safely passed to ServeHTTP handler,
 // wrapping the real response writer.
 type ProxyWriter struct {
-	W    http.ResponseWriter
-	Code int
+	W      http.ResponseWriter
+	Code   int
+	Length int64
 }
 
 func (p *ProxyWriter) StatusCode() int {
@@ -31,6 +35,7 @@ func (p *ProxyWriter) Header() http.Header {
 }
 
 func (p *ProxyWriter) Write(buf []byte) (int, error) {
+	p.Length = p.Length + int64(len(buf))
 	return p.W.Write(buf)
 }
 
@@ -45,8 +50,20 @@ func (p *ProxyWriter) Flush() {
 	}
 }
 
+func (p *ProxyWriter) CloseNotify() <-chan bool {
+	if cn, ok := p.W.(http.CloseNotifier); ok {
+		return cn.CloseNotify()
+	}
+	log.Warningf("Upstream ResponseWriter of type %v does not implement http.CloseNotifier. Returning dummy channel.", reflect.TypeOf(p.W))
+	return make(<-chan bool)
+}
+
 func (p *ProxyWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
-	return p.W.(http.Hijacker).Hijack()
+	if hi, ok := p.W.(http.Hijacker); ok {
+		return hi.Hijack()
+	}
+	log.Warningf("Upstream ResponseWriter of type %v does not implement http.Hijacker. Returning dummy channel.", reflect.TypeOf(p.W))
+	return nil, nil, fmt.Errorf("The response writer that was wrapped in this proxy, does not implement http.Hijacker. It is of type: %v", reflect.TypeOf(p.W))
 }
 
 func NewBufferWriter(w io.WriteCloser) *BufferWriter {
@@ -79,8 +96,20 @@ func (b *BufferWriter) WriteHeader(code int) {
 	b.Code = code
 }
 
+func (b *BufferWriter) CloseNotify() <-chan bool {
+	if cn, ok := b.W.(http.CloseNotifier); ok {
+		return cn.CloseNotify()
+	}
+	log.Warningf("Upstream ResponseWriter of type %v does not implement http.CloseNotifier. Returning dummy channel.", reflect.TypeOf(b.W))
+	return make(<-chan bool)
+}
+
 func (b *BufferWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
-	return b.W.(http.Hijacker).Hijack()
+	if hi, ok := b.W.(http.Hijacker); ok {
+		return hi.Hijack()
+	}
+	log.Warningf("Upstream ResponseWriter of type %v does not implement http.Hijacker. Returning dummy channel.", reflect.TypeOf(b.W))
+	return nil, nil, fmt.Errorf("The response writer that was wrapped in this proxy, does not implement http.Hijacker. It is of type: %v", reflect.TypeOf(b.W))
 }
 
 type nopWriteCloser struct {
@@ -106,11 +135,9 @@ func CopyURL(i *url.URL) *url.URL {
 
 // CopyHeaders copies http headers from source to destination, it
 // does not overide, but adds multiple headers
-func CopyHeaders(dst, src http.Header) {
+func CopyHeaders(dst http.Header, src http.Header) {
 	for k, vv := range src {
-		for _, v := range vv {
-			dst.Add(k, v)
-		}
+		dst[k] = append(dst[k], vv...)
 	}
 }
 
@@ -130,9 +157,3 @@ func RemoveHeaders(headers http.Header, names ...string) {
 		headers.Del(h)
 	}
 }
-
-// Parse the MIME media type value of a header.
-func GetHeaderMediaType(headers http.Header, name string) (string, error)  {
-	mediatype, _, err := mime.ParseMediaType(headers.Get(name))
-	return mediatype, err
-}