GRPC

官方网站

gRPCgRPC

项目地址

GitHub - grpc/grpc-go: The Go language implementation of gRPC. HTTP/2 based RPCGitHub

下载与安装

首先安装protoc

访问下方地址

Releases · protocolbuffers/protobufGitHub

根据系统类型找到合适的安装包下载后解压，将其中的二进制文件移入$PATH目录中，将其中的include/目录下的文件复制到/usr/local/lib/目录下

接着安装 protoc-gen-go 插件

go install google.golang.org/protobuf/cmd/protoc-gen-go@v1.28
go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@v1.2

最后下载 grpc 库

go get -u google.golang.org/grpc

如果无法访问外网则使用以下方式

git clone https://github.com/grpc/grpc-go.git $GOPATH/src/google.golang.org/grpc
git clone [e-mail]:googleapis/go-genproto.git $GOPATH/src/google.golang.org/genproto

例子

简单grpc服务

server/main.go

package main

import (
	"context"
	"log"
	"net"

	"google.golang.org/grpc"
	
	"demo/rpc/grpc/simple/protos/pb"
)

const (
	port = "localhost:9090"
)

type server struct{}

func (s *server) Echo(ctx context.Context, in *pb.StringMessage) (*pb.StringMessage, error) {
	log.Printf("Received: %v", in.Value)
	return &pb.StringMessage{Value: "Hello " + in.Value}, nil
}

func main() {
	lis, err := net.Listen("tcp", port)
	if err != nil {
		log.Fatalf("failed to listen: %v", err)
	}
	s := grpc.NewServer()
	pb.RegisterYourServiceServer(s, &server{})
	if err := s.Serve(lis); err != nil {
		log.Fatalf("failed to serve: %v", err)
	}
}

client/main.go

package main

import (
	"context"
	"log"
	"os"
	"time"

	"google.golang.org/grpc"
	
	"demo/rpc/grpc/simple/protos/pb"
)

const (
	address     = "localhost:9090"
	defaultName = "world"
)

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

	name := defaultName
	if len(os.Args) > 1 {
		name = os.Args[1]
	}
	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
	defer cancel()
	r, err := c.Echo(ctx, &pb.StringMessage{Value: name})
	if err != nil {
		log.Fatalf("could not greet: %v", err)
	}
	log.Printf("Greeting: %s", r.Value)
}

protos/helloworld.proto

syntax = "proto3";
option go_package = "/pb";

package example;

message StringMessage {
  string value = 1;
}

service YourService {
  rpc Echo(StringMessage) returns (StringMessage) {}
}

执行命令

protoc --go_out=./protos --go-grpc_out=./protos --proto_path=./protos protos/*.proto

这时 protos/ 目录下会生成 helloworld.pb.go 和 helloworld_grpc.pb.go 文件，该文件是 grpc 接口以及相关参数的定义

执行以下命令启动GRPC服务端

go run server/main.go

执行以下命令执行GRPC客户端

go run client/main.go

服务端输出

2019/06/25 17:32:09 Received: world

客户端输出

2019/06/25 17:32:09 Greeting: Hello world