go与grpc

参考：

https://github.com/grpc/grpc-go

http://doc.oschina.net/grpc?t=60133

---

快速入门

建议grpc服务分三步：写proto文件、写serve、写client

proto文件

建立文件：proto/ServeRoute.proto

syntax = "proto3"; // 指定proto版本
package proto;     // 指定包名

//定义传输过程用到的数据类型,数字代表内部成员序号
message Name {
    string name = 1;
}
message Msg1 {
    string message = 1;
}
message Msg2 {
    Msg1 message = 1;
}

//定义提供的服务
service ServeRoute{
    rpc Serve1(Name) returns (Msg1) {}
    rpc Serve2(Name) returns (Msg2) {}
}

在proto文件所在的文件夹输入下面命令，生产pb.go文件

protoc --go_out=plugins=grpc:. ServeRoute.proto

serve文件

建立serve/serve.go

package main

import (
	pb "../proto" // 引入编译生成的包
	"golang.org/x/net/context"
	"google.golang.org/grpc"
	"log"
	"net"
)
//通过一个结构体，实现proto中定义的所有服务
type ServeRoute struct{}

func (h ServeRoute) Serve1(ctx context.Context, in *pb.Name) (*pb.Msg1, error) {
	log.Println("serve 1 works: get name: ", in.Name)
	resp := &pb.Msg1{Message:"this is serve 1"}
	return resp, nil
}

func (h ServeRoute) Serve2(ctx context.Context, in *pb.Name) (*pb.Msg2, error) {
	log.Println("serve 2 works, get name: ", in.Name)
	resp := &pb.Msg2{
		Message:&pb.Msg1{Message:"this is serve 2"},
	}
	return resp, nil
}
func main() {
	listen, err := net.Listen("tcp", "127.0.0.1:50052") // Address gRPC服务地址
	if err != nil {
		log.Fatalf("failed to listen: %v", err)
	}
	s := grpc.NewServer()
	// 与http的注册路由类似，此处将所有服务注册到grpc服务器上，
	pb.RegisterServeRouteServer(s, ServeRoute{})
	log.Println("grpc serve running")
	if err := s.Serve(listen); err != nil{
		log.Fatal(err)
	}
}

client文件

建立client/client.go（与serve分别为独立项目）

package main
import (
pb "../proto" // 引入proto包
"golang.org/x/net/context"
"google.golang.org/grpc"
"log"
)

func main() {
	conn, err := grpc.Dial("127.0.0.1:50052", grpc.WithInsecure())
	if err != nil {
		log.Fatalln(err)
	}
	defer conn.Close()
	c := pb.NewServeRouteClient(conn)

	reqBody1 := &pb.Name{Name:"wang"}
	res1, err := c.Serve1(context.Background(), reqBody1)  //就像调用本地函数一样，通过serve1得到返回值
	if err != nil {
		log.Fatalln(err)
	}
	log.Println("message from serve: ", res1.Message)

	reqBody2 := &pb.Name{Name:"li"}
	res2, err := c.Serve2(context.Background(), reqBody2)  //就像调用本地函数一样，通过serve2得到返回值
	if err != nil {
		log.Fatalln(err)
	}
	log.Println("message from serve: ", res2.Message.Message)
}

运行

 

运行serve.go之后
serve端等待请求：
2019/07/04 20:37:40 grpc serve running

运行client.go之后
serve端：
2019/07/04 20:37:51 serve 1 works: get name:  wang
2019/07/04 20:37:51 serve 2 works, get name:  li
client端：
2019/07/04 20:37:51 message from serve:  this is serve 1
2019/07/04 20:37:51 message from serve:  this is serve 2