From 5682f53f386312e5b1413996ec2b8fc5aa6e5d34 Mon Sep 17 00:00:00 2001
From: salamer <salamer_gaga@163.com>
Date: Sun, 12 Aug 2018 14:46:43 +0800
Subject: [PATCH 1/2] Add support for Protobuf format response

---
 context.go         |  6 ++++++
 render/protobuf.go | 33 +++++++++++++++++++++++++++++++++
 render/render.go   |  1 +
 3 files changed, 40 insertions(+)
 create mode 100644 render/protobuf.go

diff --git a/context.go b/context.go
index 724ded79..c73748eb 100644
--- a/context.go
+++ b/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 *******/
 /************************************/
diff --git a/render/protobuf.go b/render/protobuf.go
new file mode 100644
index 00000000..eb34619c
--- /dev/null
+++ b/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)
+}
diff --git a/render/render.go b/render/render.go
index 4ff1c7b6..df0d1d7c 100755
--- a/render/render.go
+++ b/render/render.go
@@ -27,6 +27,7 @@ var (
 	_ Render     = MsgPack{}
 	_ Render     = Reader{}
 	_ Render     = AsciiJSON{}
+	_ Render     = ProtoBuf{}
 )
 
 func writeContentType(w http.ResponseWriter, value []string) {

From 73b20fdb2aaa35d36347d377accc1a4a637633d8 Mon Sep 17 00:00:00 2001
From: salamer <salamer_gaga@163.com>
Date: Sun, 12 Aug 2018 15:32:35 +0800
Subject: [PATCH 2/2] add RenderProtoBuf test

---
 context_test.go | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/context_test.go b/context_test.go
index 0185507f..a8cb4d10 100644
--- a/context_test.go
+++ b/context_test.go
@@ -17,11 +17,14 @@ import (
 	"testing"
 	"time"
 
+	"io"
+
 	"github.com/gin-contrib/sse"
 	"github.com/gin-gonic/gin/binding"
+	pb "github.com/gin-gonic/gin/examples/grpc/pb"
+	"github.com/golang/protobuf/proto"
 	"github.com/stretchr/testify/assert"
 	"golang.org/x/net/context"
-	"io"
 )
 
 var _ context.Context = &Context{}
@@ -953,6 +956,23 @@ func TestContextRenderYAML(t *testing.T) {
 	assert.Equal(t, "application/x-yaml; charset=utf-8", w.HeaderMap.Get("Content-Type"))
 }
 
+// TestContextRenderProtoBuf tests that the response is serialized as YAML
+// and Content-Type is set to application/x-protobuf
+// and we just use the example protobuf to check if the response is correct
+func TestContextRenderProtoBuf(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+
+	c.ProtoBuf(201, &pb.HelloRequest{Name: "Hello"})
+
+	realProtoBuf, err := proto.Marshal(&pb.HelloRequest{Name: "Hello"})
+	assert.Nil(t, err)
+
+	assert.Equal(t, 201, w.Code)
+	assert.Equal(t, realProtoBuf, w.Body.Bytes())
+	assert.Equal(t, "application/x-protobuf", w.HeaderMap.Get("Content-Type"))
+}
+
 func TestContextHeaders(t *testing.T) {
 	c, _ := CreateTestContext(httptest.NewRecorder())
 	c.Header("Content-Type", "text/plain")