1、获取gRPC
环境变量GOPATH的src目录下执行：
git clone https://github.com/grpc/grpc-go.git google.golang.org/grpc
git clone https://github.com/golang/net.git golang.org/x/net
git clone https://github.com/golang/text.git golang.org/x/text
go get -u github.com/golang/protobuf/protoc-gen-go
git clone https://github.com/google/go-genproto.git google.golang.org/genproto
go install google.golang.org/grpc
2、proto文件
gRPC 允许定义4种类型的 service 方法。
（1）编写test.proto
syntax = "proto3";
package test;
//参数
message Question{
string question_str = 1;
}
//返回
message Answer{
string answer_str = 1;
}
//定义服务
service Test{
//简单RPC
rpc GetAnswer1(Question) returns (Answer){}
//服务端流式RPC
rpc GetAnswer2(Question) returns (stream Answer){}
//客户端流式RPC
rpc GetAnswer3(stream Question) returns (Answer){}
//双向流式RPC
rpc GetAnswer4(stream Question) returns (stream Answer){}
}
（2）生成文件test.pb.go
protoc --go_out=plugins=grpc:. test.proto
3、服务端
package main
import (
"context"
"fmt"
"io"
"log"
"net"
"test/grpc/test"
"google.golang.org/grpc"
)
type testServer struct{}
//简单RPC
//客户端一次请求，服务端一次响应
func (*testServer) GetAnswer1(ctx context.Context, q *test.Question) (*test.Answer, error) {
answer := test.Answer{AnswerStr: fmt.Sprintf("Question：%s；Answer：%s。", q.QuestionStr, "Answer1")}
return &answer, nil
}
//服务端流式RPC
//客户端一次请求，服务端多次响应
func (*testServer) GetAnswer2(q *test.Question, stream test.Test_GetAnswer2Server) error {
for i := 1; i <= 3; i++ {
answer := test.Answer{AnswerStr: fmt.Sprintf("Question：%s；Answer：%s%d。", q.QuestionStr, "Answer", i)}
if err := stream.Send(&answer); err != nil {
return err
}
}
return nil
}
//客户端流式RPC
//客户端多次请求，服务端一次响应
func (*testServer) GetAnswer3(stream test.Test_GetAnswer3Server) error {
answer := test.Answer{}
for i := 1; ; i++ {
question, err := stream.Recv()
if err == io.EOF {
return stream.SendAndClose(&answer)
}
if err != nil {
return err
}
answer.AnswerStr = fmt.Sprintf("%sQuestion：%s;Answer：Answer%d。\n", answer.AnswerStr, question.QuestionStr, i)
}
}
//双向流式RPC
//客户端多次请求，服务端多次响应
func (*testServer) GetAnswer4(stream test.Test_GetAnswer4Server) error {
for i := 1; ; i++ {
question, err := stream.Recv()
if err == io.EOF {
return nil
}
if err != nil {
return err
}
answer := test.Answer{AnswerStr: fmt.Sprintf("Question：%s；Answer：%s%d。", question.QuestionStr, "Answer", i)}
if err = stream.Send(&answer); err != nil {
return err
}
}
}
func main() {
lis, err := net.Listen("tcp", "127.0.0.1:5000")
if err != nil {
log.Fatalf("failed to listen: %v", err)
}
grpcServer := grpc.NewServer()
test.RegisterTestServer(grpcServer, &testServer{})
grpcServer.Serve(lis)
}
4、客户端
package main
import (
"context"
"fmt"
"io"
"log"
"test/grpc/test"
"google.golang.org/grpc"
)
func main() {
conn, err := grpc.Dial("127.0.0.1:5000", grpc.WithInsecure())
if err != nil {
log.Fatalf("fail to dial: %v", err)
}
defer conn.Close()
client := test.NewTestClient(conn)
fmt.Println("简单RPC===========================")
question := test.Question{QuestionStr: "问题11111111？"}
answer, err := client.GetAnswer1(context.Background(), &question)
if err != nil {
log.Fatalf("fail to GetAnswer1: %v", err)
}
fmt.Println(answer.AnswerStr)
fmt.Println("服务端流式RPC===========================")
stream, err := client.GetAnswer2(context.Background(), &question)
if err != nil {
log.Fatalf("fail to GetAnswer2: %v", err)
}
for {
answer, err := stream.Recv()
if err == io.EOF {
break
}
if err != nil {
log.Fatalf("%v.GetAnswer2, %v", client, err)
}
fmt.Println(answer.AnswerStr)
}
fmt.Println("客户端流式RPC===========================")
stream3, err := client.GetAnswer3(context.Background())
if err != nil {
log.Fatalf("fail to GetAnswer3: %v", err)
}
for i := 1; i <= 3; i++ {
question := test.Question{QuestionStr: fmt.Sprintf("问题%d", i)}
if err = stream3.Send(&question); err != nil {
log.Fatalf("fail to GetAnswer3 Send: %v", err)
}
}
answer, err = stream3.CloseAndRecv()
if err != nil {
log.Fatalf("fail to GetAnswer3 CloseAndRecv: %v", err)
}
fmt.Println(answer.AnswerStr)
fmt.Println("双向流式RPC===============================")
done := make(chan bool)
stream4, err := client.GetAnswer4(context.Background())
if err != nil {
log.Fatalf("fail to GetAnswer4: %v", err)
}
//接受服务端响应
go func() {
for {
answer, err := stream4.Recv()
if err == io.EOF {
close(done)
return
}
if err != nil {
log.Fatalf("%v.GetAnswer4, %v", client, err)
}
fmt.Println(answer.AnswerStr)
}
}()
//客户端发送请求
for i := 1; i <= 4; i++ {
question := test.Question{QuestionStr: fmt.Sprintf("问题%d", i)}
if err = stream4.Send(&question); err != nil {
log.Fatalf("fail to GetAnswer3 Send: %v", err)
}
}
stream4.CloseSend()
<-done
}
5、输出
// 简单RPC=========================== // Question：问题11111111？；Answer：Answer1。 // 服务端流式RPC=========================== // Question：问题11111111？；Answer：Answer1。 // Question：问题11111111？；Answer：Answer2。 // Question：问题11111111？；Answer：Answer3。 // 客户端流式RPC=========================== // Question：问题1;Answer：Answer1。 // Question：问题2;Answer：Answer2。 // Question：问题3;Answer：Answer3。 // 双向流式RPC=============================== // Question：问题1；Answer：Answer1。 // Question：问题2；Answer：Answer2。 // Question：问题3；Answer：Answer3。 // Question：问题4；Answer：Answer4。
原文：https://www.cnblogs.com/dzhy/p/11103429.html