gRPC的Go语言使用例子

        gRPC刚被Google开源， gRPC是啥? 先照抄一段说明:
gRPC是一个高性能、通用的开源RPC框架，其由Google主要面向移动应用开发并基于HTTP/2协议标准而设计，基于ProtoBuf(Protocol Buffers)序列化协议开发，且支持众多开发语言。gRPC提供了一种简单的方法来精确地定义服务和为iOS、Android和后台支持服务自动生成可靠性很强的客户端功能库。客户端充分利用高级流和链接功能，从而有助于节省带宽、降低的TCP链接次数、节省CPU使用、和电池寿命。

   这段抄自info: http://www.infoq.com/cn/news/2015/03/grpc-google-http2-protobuf

    官网地址: http://www.grpc.io  

冲着面向移动应用开发这点，值得一试，参考其说明文档,用Golang弄了个例子:

1. 先创建一个rpcsrv.proto文件:

syntax = "proto3";

package xcl;



enum UserStatus {
    OFFLINE = 0;
    ONLINE = 1;
 }

message UserInfo {
  int32 id = 1; 
  string name = 2; 
  UserStatus status = 3 ;
}

message UserID {
  int32 id = 1; 
}

message funcResponse {    
   string reply = 1;
}

service UserService {
  rpc Login(UserInfo) returns (funcResponse){};
  rpc logout(UserID) returns (funcResponse){};
}

    主要的几个struct:     

type UserInfo struct {
	Id     int32      `protobuf:"varint,1,opt,name=id" json:"id,omitempty"`
	Name   string     `protobuf:"bytes,2,opt,name=name" json:"name,omitempty"`
	Status UserStatus `protobuf:"varint,3,opt,name=status,enum=xcl.UserStatus" json:"status,omitempty"`
}

type UserID struct {
	Id int32 `protobuf:"varint,1,opt,name=id" json:"id,omitempty"`
}


type FuncResponse struct {
	Reply string `protobuf:"bytes,1,opt,name=reply" json:"reply,omitempty"`
}

  3. RPC服务端

//gRPC例子-服务端
//author: Xiong Chuan Liang
//date: 2015-3-8

package main

import (
	pb "xcl"

	"log"
	"net"
	"os"

	"golang.org/x/net/context"
	"google.golang.org/grpc"
)

func main() {

	log.SetOutput(os.Stdout)
	lis, err := net.Listen("tcp", port)
	if err != nil {
		log.Fatalf("failed to listen: %v", err)
	}
	s := grpc.NewServer()
	pb.RegisterUserServiceServer(s, &server{})

	log.Println("Server......")
	s.Serve(lis)

}

const (
	port = ":50051"
)

type server struct{}

func (s *server) Login(ctx context.Context, usr *pb.UserInfo) (*pb.FuncResponse, error) {
	log.Println("Server...... Login() UserInfo:", usr)

	usr.Id = 100
	strId := "100" //strconv.Itoa(usr.Id)

	return &pb.FuncResponse{Reply: strId}, nil

}

func (s *server) Logout(ctx context.Context, uid *pb.UserID) (*pb.FuncResponse, error) {
	log.Println("Server...... Logout() UserID:", uid)
	return &pb.FuncResponse{Reply: "Logout Successed."}, nil
}

4. 客户端:

//gRPC例子-客户端
//author: Xiong Chuan Liang
//date: 2015-3-8

package main

import (
	"log"
	"os"
	"strconv"

	pb "xcl"

	"golang.org/x/net/context"
	"google.golang.org/grpc"
)

const (
	address = "localhost:50051"
)

func main() {
	log.SetOutput(os.Stdout)

	conn, err := grpc.Dial(address)
	if err != nil {
		log.Fatalf("did not connect: %v", err)
	}
	defer conn.Close()
	c := pb.NewUserServiceClient(conn)

	var status pb.UserStatus
	status = pb.UserStatus_ONLINE

	userInfo := &pb.UserInfo{
		//Id:     10,         //proto.Int32(10),
		Name:   "XCL-gRPC", //proto.String("XCL-gRPC"),
		Status: status,
	}

	r, err := c.Login(context.Background(), userInfo)
	if err != nil {
		log.Fatalf("登录失败!  %v", err)
	}
	log.Println("Login():", r)

	uid, err := strconv.ParseInt(r.Reply, 10, 32)
	if err != nil {
		log.Fatalf("非数字  %v", err)
	}

	userID := &pb.UserID{int32(uid)}
	out, err := c.Logout(context.Background(), userID)
	log.Println("Logout():", out)
}

 gRPC 跑起来了，内部的东西还没去细究。不过app服务端相关的话，应当值得一试。

MAIL: xcl_168@aliyun.com

BLOG:http://blog.csdn.net/xcl168

原文：http://blog.csdn.net/xcl168/article/details/44137627