grpc

```go package main import ( "StudyGin/helloWorld" "context" "fmt" "google.golang.org/grpc" "google.golang.org/grpc/grpclog" "net" ) type HelloService struct { helloWorld.UnimplementedHelloServer } func (h *HelloService) SayHello(ctx context.Context, request *helloWorld.HelloRequest) (*helloWorld.HelloResponse,error){ // 或者rsp := new(helloWorld.HelloResponse) var rsp helloWorld.HelloResponse rsp.Message= fmt.Sprintf("Hello %s",request.Name) return &rsp,nil } func main() { //实例化grpc Server s:=grpc.NewServer() //注册HelloService var helloService HelloService helloWorld.RegisterHelloServer(s,&helloService) // 启动 lis, err := net.Listen("tcp", "0.0.0.0:8080") if err != nil { grpclog.Fatalf("Failed to listen: %v", err) } err = s.Serve(lis) if err != nil { return } } ``` **在学习grpc的时候，看教程服务端定义结构体不需要继承helloWorld.UnimplementedHelloServer，为什么现在需要 ? Go版本1.17**