Add support for Protobuf format response

context.go

@@ -20,6 +20,7 @@ import (
 	"github.com/gin-contrib/sse"
 	"github.com/gin-gonic/gin/binding"
 	"github.com/gin-gonic/gin/render"
+	"github.com/golang/protobuf/proto"
 )
 
 // Content-Type MIME of the most common data formats.
@@ -835,6 +836,11 @@ func (c *Context) Stream(step func(w io.Writer) bool) {
 	}
 }
 
+// ProtoBuf serializes the given struct as ProtoBuf into the response body.
+func (c *Context) ProtoBuf(code int, obj proto.Message) {
+	c.Render(code, render.ProtoBuf{Data: obj})
+}
+
 /************************************/
 /******** CONTENT NEGOTIATION *******/
 /************************************/

render/protobuf.go

@@ -0,0 +1,33 @@
+// Copyright 2014 Manu Martinez-Almeida.  All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package render
+
+import (
+	"net/http"
+
+	"github.com/golang/protobuf/proto"
+)
+
+type ProtoBuf struct {
+	Data proto.Message
+}
+
+var protobufContentType = []string{"application/x-protobuf"}
+
+func (r ProtoBuf) Render(w http.ResponseWriter) error {
+	r.WriteContentType(w)
+
+	bytes, err := proto.Marshal(r.Data)
+	if err != nil {
+		return err
+	}
+
+	w.Write(bytes)
+	return nil
+}
+
+func (r ProtoBuf) WriteContentType(w http.ResponseWriter) {
+	writeContentType(w, protobufContentType)
+}

render/render.go

@@ -27,6 +27,7 @@ var (
 	_ Render     = MsgPack{}
 	_ Render     = Reader{}
 	_ Render     = AsciiJSON{}
+	_ Render     = ProtoBuf{}
 )
 
 func writeContentType(w http.ResponseWriter, value []string) {