the net/http should set header first,the set http status code and then write the content

context/context.go

@@ -59,7 +59,10 @@ type Context struct {
 // Reset init Context, BeegoInput and BeegoOutput
 func (ctx *Context) Reset(rw http.ResponseWriter, r *http.Request) {
 	ctx.Request = r
-	ctx.ResponseWriter = &Response{rw, false, 0}
+	if ctx.ResponseWriter == nil {
+		ctx.ResponseWriter = &Response{}
+	}
+	ctx.ResponseWriter.reset(rw)
 	ctx.Input.Reset(ctx)
 	ctx.Output.Reset(ctx)
 }
@@ -174,6 +177,14 @@ type Response struct {
 	http.ResponseWriter
 	Started     bool
 	Status      int
+	wroteHeader bool
+}
+
+func (r *Response) reset(rw http.ResponseWriter) {
+	r.ResponseWriter = rw
+	r.Status = 0
+	r.Started = false
+	r.wroteHeader = false
 }
 
 // Write writes the data to the connection as part of an HTTP reply,
@@ -181,6 +192,11 @@ type Response struct {
 // started means the response has sent out.
 func (w *Response) Write(p []byte) (int, error) {
 	w.Started = true
+	if !w.wroteHeader {
+		w.ResponseWriter.WriteHeader(w.Status)
+		//prevent multiple response.WriteHeader calls
+		w.wroteHeader = true
+	}
 	return w.ResponseWriter.Write(p)
 }
 
@@ -188,12 +204,10 @@ func (w *Response) Write(p []byte) (int, error) {
 // and sets `started` to true.
 func (w *Response) WriteHeader(code int) {
 	if w.Status > 0 {
-		//prevent multiple response.WriteHeader calls
 		return
 	}
 	w.Status = code
 	w.Started = true
-	w.ResponseWriter.WriteHeader(code)
 }
 
 // Hijack hijacker for http

router.go

@@ -607,6 +607,7 @@ func (p *ControllerRegister) ServeHTTP(rw http.ResponseWriter, r *http.Request)
 	)
 	context := p.pool.Get().(*beecontext.Context)
 	context.Reset(rw, r)
+
 	defer p.pool.Put(context)
 	defer p.recoverPanic(context)
 
@@ -616,8 +617,6 @@ func (p *ControllerRegister) ServeHTTP(rw http.ResponseWriter, r *http.Request)
 		context.Output.Header("Server", BConfig.ServerName)
 	}
 
-	context.Output.Header("Content-Type", "text/html; charset=utf-8")
-
 	var urlPath string
 	if !BConfig.RouterCaseSensitive {
 		urlPath = strings.ToLower(r.URL.Path)