add http hijack methods (#555)

rest/handler/loghandler.go

@@ -1,10 +1,12 @@
 package handler
 
 import (
+	"bufio"
 	"bytes"
 	"context"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"net/http/httputil"
 	"time"
@@ -25,10 +27,22 @@ type loggedResponseWriter struct {
 	code int
 }
 
+func (w *loggedResponseWriter) Flush() {
+	if flusher, ok := w.w.(http.Flusher); ok {
+		flusher.Flush()
+	}
+}
+
 func (w *loggedResponseWriter) Header() http.Header {
 	return w.w.Header()
 }
 
+// Hijack implements the http.Hijacker interface.
+// This expands the Response to fulfill http.Hijacker if the underlying http.ResponseWriter supports it.
+func (w *loggedResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	return w.w.(http.Hijacker).Hijack()
+}
+
 func (w *loggedResponseWriter) Write(bytes []byte) (int, error) {
 	return w.w.Write(bytes)
 }
@@ -38,12 +52,6 @@ func (w *loggedResponseWriter) WriteHeader(code int) {
 	w.code = code
 }
 
-func (w *loggedResponseWriter) Flush() {
-	if flusher, ok := w.w.(http.Flusher); ok {
-		flusher.Flush()
-	}
-}
-
 // LogHandler returns a middleware that logs http request and response.
 func LogHandler(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {