not use protobuf on context but use it on render (#1496)

render/protobuf.go

@@ -11,7 +11,7 @@ import (
 )
 
 type ProtoBuf struct {
-	Data proto.Message
+	Data interface{}
 }
 
 var protobufContentType = []string{"application/x-protobuf"}
@@ -19,7 +19,7 @@ var protobufContentType = []string{"application/x-protobuf"}
 func (r ProtoBuf) Render(w http.ResponseWriter) error {
 	r.WriteContentType(w)
 
-	bytes, err := proto.Marshal(r.Data)
+	bytes, err := proto.Marshal(r.Data.(proto.Message))
 	if err != nil {
 		return err
 	}

render/render_test.go

@@ -15,10 +15,11 @@ import (
 	"strings"
 	"testing"
 
-	testdata "github.com/gin-gonic/gin/testdata/protoexample"
 	"github.com/golang/protobuf/proto"
 	"github.com/stretchr/testify/assert"
 	"github.com/ugorji/go/codec"
+
+	testdata "github.com/gin-gonic/gin/testdata/protoexample"
 )
 
 // TODO unit tests