add Context.ReadJSONProtobuf method

Former-commit-id: 9c7f268c0d7be7e405ea97a5ac12257beba3a4f3

_examples/response-writer/protobuf/main.go

@@ -0,0 +1,60 @@
+package main
+
+import (
+	"app/protos"
+
+	"github.com/kataras/iris/v12"
+)
+
+func main() {
+	app := iris.New()
+
+	app.Get("/", send)
+	app.Get("/json", sendAsJSON)
+	app.Post("/read", read)
+	app.Post("/read_json", readFromJSON)
+
+	app.Listen(":8080")
+}
+
+func send(ctx iris.Context) {
+	response := &protos.HelloReply{Message: "Hello, World!"}
+	ctx.Protobuf(response)
+}
+
+func sendAsJSON(ctx iris.Context) {
+	response := &protos.HelloReply{Message: "Hello, World!"}
+	options := iris.JSON{
+		Proto: iris.ProtoMarshalOptions{
+			AllowPartial: true,
+			Multiline:    true,
+			Indent:       "    ",
+		},
+	}
+
+	ctx.JSON(response, options)
+}
+
+func read(ctx iris.Context) {
+	var request protos.HelloRequest
+
+	err := ctx.ReadProtobuf(&request)
+	if err != nil {
+		ctx.StopWithError(iris.StatusBadRequest, err)
+		return
+	}
+
+	ctx.Writef("HelloRequest.Name = %s", request.Name)
+}
+
+func readFromJSON(ctx iris.Context) {
+	var request protos.HelloRequest
+
+	err := ctx.ReadJSONProtobuf(&request)
+	if err != nil {
+		ctx.StopWithError(iris.StatusBadRequest, err)
+		return
+	}
+
+	ctx.Writef("HelloRequest.Name = %s", request.Name)
+}