定义 gRPC的.proto
syntax = "proto3";
package helloworld;
// The greeting service definition.
service Greeter {
// Sends a greeting
rpc SayHello (HelloRequest) returns (HelloReply) {}
}
// The request message containing the user's name.
message HelloRequest {
string name = 1;
}
// The response message containing the greetings
message HelloReply {
string message = 1;
}
Generate gRPC code
Next we need to update the gRPC code used by our application to use the new service definition. From the same examples dir as above ($GOPATH/src/google.golang.org/grpc/examples/helloworld)
$ protoc -I helloworld/ helloworld/helloworld.proto --go_out=plugins=grpc:helloworld
一个官方的 Demo
client.go
// Package main implements a client for Greeter service.
package main
import (
"context"
//pb "google.golang.org/grpc/examples/helloworld/helloworld"
"log"
"os"
"time"
pb "awesomeProject/protobufsw"
"google.golang.org/grpc"
//pb "google.golang.org/grpc/examples/helloworld/helloworld"
)
const (
address = "localhost:50051"
defaultName = "world"
)
func main() {
// Set up a connection to the server.
conn, err := grpc.Dial(address, grpc.WithInsecure(), grpc.WithBlock())
if err != nil {
log.Fatalf("did not connect: %v", err)
}
defer conn.Close()
c := pb.NewGreeterClient(conn)
// Contact the server and print out its response.
name := defaultName
if len(os.Args) > 1 {
name = os.Args[1]
}
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
defer cancel()
r, err := c.SayHello(ctx, &pb.HelloRequest{Name: name})
if err != nil {
log.Fatalf("could not greet: %v", err)
}
log.Printf("Greeting: %s", r.GetMessage())
}
server.go
//go:generate protoc -I ../helloworld --go_out=plugins=grpc:../helloworld ../helloworld/helloworld.proto
// Package main implements a server for Greeter service.
package main
import (
"context"
//pb "google.golang.org/grpc/examples/helloworld/helloworld"
"log"
"net"
"google.golang.org/grpc"
pb "awesomeProject/protobufsw"
//pb "google.golang.org/grpc/examples/helloworld/helloworld"
)
const (
port = ":50051"
)
// server is used to implement helloworld.GreeterServer.
type server struct {
pb.UnimplementedGreeterServer
}
// SayHello implements helloworld.GreeterServer
func (s *server) SayHello(ctx context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
log.Printf("Received: %v", in.GetName())
return &pb.HelloReply{Message: "Hello " + in.GetName()}, nil
}
func main() {
lis, err := net.Listen("tcp", port)
if err != nil {
log.Fatalf("failed to listen: %v", err)
}
s := grpc.NewServer()
pb.RegisterGreeterServer(s, &server{})
if err := s.Serve(lis); err != nil {
log.Fatalf("failed to serve: %v", err)
}
}
api.go
syntax = "proto3";
option java_multiple_files = true;
option java_package = "io.grpc.examples.helloworld";
option java_outer_classname = "HelloWorldProto";
package protobufsw;
// The greeting service definition.
service Greeter {
// Sends a greeting
rpc SayHello (HelloRequest) returns (HelloReply) {}
}
// The request message containing the user's name.
message HelloRequest {
string name = 1;
}
// The response message containing the greetings
message HelloReply {
string message = 1;
}
执行 protoc -I protobufsw/ protobufsw/api.proto --go_out=plugins=grpc:protobufsw 以将 api.go 生成 api.pb.go。此后，就可以运行 server.go 和 client.go