メモとしてgRPC通信のサンプル実装を残す。
【環境について】
・go version:go1.19.2
・protoc version:libprotoc 22.0
・protoc-gen-go version:v1.28.0
・protoc-gen-go-grpc version:1.2.0
フォルダ構成
grpc
├─go.mod
├─go.sum
└─examples
│
├─greeter_client
│ └ main.go
├─greeter_server
│ └ main.go
└─helloworld
├ helloworld.pb.go
├ helloworld.proto
└ helloworld_grpc.pb.go
【protocを設定】
■protocをインストール
①こちらから「protoc-xxx-win32.zip」を取得。
■環境変数の設定
①コントロールパネル>システムとセキュリティ>システムを開く
②システム詳細設定をクリックしてシステムプロパティを開く
③環境変数をクリック
④「新規」をクリックして変数名と値(protocを保存しておきたいパス)を設定。
⑤変数:Pathにカーソルを合わせて「編集」をクリック。
⑥環境変数名の編集画面で「新規」をクリックして値(protocを保存しておきたいパス)を入力
⑦コマンドプロンプト等で「protoc --version」を入力して下記のように表示される事を確認
protoc --version
libprotoc 22.0
【gRPCをインストール】
※前提:go modファイルを作成してから実施して下さい。$ go get -u google.golang.org/grpc
protoc-gen-go,protoc-gen-go-grpcをインストール
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
protoファイルの作成
syntax = "proto3";
// option java_multiple_files = true;
// option java_package = "io.grpc.examples.helloworld";
// option java_outer_classname = "HelloWorldProto";
// option go_package = "proto/;proto";
option go_package = "google.golang.org/grpc/examples/helloworld/helloworld";
option java_multiple_files = true;
option java_package = "io.grpc.examples.helloworld";
option java_outer_classname = "HelloWorldProto";
package proto;
// 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;
}
作成後下記コマンドを実行
protoc --go_out=. --go-grpc_out=./helloworld ./helloworld/*.proto
「helloworld.pb.go」と「helloworld_grpc.pb.go」が作成出来ている事を確認。
helloworld.pb.go
// Code generated by protoc-gen-go. DO NOT EDIT.
// versions:
// protoc-gen-go v1.28.0
// protoc v4.22.0
// source: helloworld/helloworld.proto
package helloworld
import (
protoreflect "google.golang.org/protobuf/reflect/protoreflect"
protoimpl "google.golang.org/protobuf/runtime/protoimpl"
reflect "reflect"
sync "sync"
)
const (
// Verify that this generated code is sufficiently up-to-date.
_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
// Verify that runtime/protoimpl is sufficiently up-to-date.
_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
)
// The request message containing the user's name.
type HelloRequest struct {
state protoimpl.MessageState
sizeCache protoimpl.SizeCache
unknownFields protoimpl.UnknownFields
Name string `protobuf:"bytes,1,opt,name=name,proto3" json:"name,omitempty"`
}
func (x *HelloRequest) Reset() {
*x = HelloRequest{}
if protoimpl.UnsafeEnabled {
mi := &file_helloworld_helloworld_proto_msgTypes[0]
ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
ms.StoreMessageInfo(mi)
}
}
func (x *HelloRequest) String() string {
return protoimpl.X.MessageStringOf(x)
}
func (*HelloRequest) ProtoMessage() {}
func (x *HelloRequest) ProtoReflect() protoreflect.Message {
mi := &file_helloworld_helloworld_proto_msgTypes[0]
if protoimpl.UnsafeEnabled && x != nil {
ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
if ms.LoadMessageInfo() == nil {
ms.StoreMessageInfo(mi)
}
return ms
}
return mi.MessageOf(x)
}
// Deprecated: Use HelloRequest.ProtoReflect.Descriptor instead.
func (*HelloRequest) Descriptor() ([]byte, []int) {
return file_helloworld_helloworld_proto_rawDescGZIP(), []int{0}
}
func (x *HelloRequest) GetName() string {
if x != nil {
return x.Name
}
return ""
}
// The response message containing the greetings
type HelloReply struct {
state protoimpl.MessageState
sizeCache protoimpl.SizeCache
unknownFields protoimpl.UnknownFields
Message string `protobuf:"bytes,1,opt,name=message,proto3" json:"message,omitempty"`
}
func (x *HelloReply) Reset() {
*x = HelloReply{}
if protoimpl.UnsafeEnabled {
mi := &file_helloworld_helloworld_proto_msgTypes[1]
ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
ms.StoreMessageInfo(mi)
}
}
func (x *HelloReply) String() string {
return protoimpl.X.MessageStringOf(x)
}
func (*HelloReply) ProtoMessage() {}
func (x *HelloReply) ProtoReflect() protoreflect.Message {
mi := &file_helloworld_helloworld_proto_msgTypes[1]
if protoimpl.UnsafeEnabled && x != nil {
ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
if ms.LoadMessageInfo() == nil {
ms.StoreMessageInfo(mi)
}
return ms
}
return mi.MessageOf(x)
}
// Deprecated: Use HelloReply.ProtoReflect.Descriptor instead.
func (*HelloReply) Descriptor() ([]byte, []int) {
return file_helloworld_helloworld_proto_rawDescGZIP(), []int{1}
}
func (x *HelloReply) GetMessage() string {
if x != nil {
return x.Message
}
return ""
}
var File_helloworld_helloworld_proto protoreflect.FileDescriptor
var file_helloworld_helloworld_proto_rawDesc = []byte{
0x0a, 0x1b, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x77, 0x6f, 0x72, 0x6c, 0x64, 0x2f, 0x68, 0x65, 0x6c,
0x6c, 0x6f, 0x77, 0x6f, 0x72, 0x6c, 0x64, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x05, 0x70,
0x72, 0x6f, 0x74, 0x6f, 0x22, 0x22, 0x0a, 0x0c, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x52, 0x65, 0x71,
0x75, 0x65, 0x73, 0x74, 0x12, 0x12, 0x0a, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x18, 0x01, 0x20, 0x01,
0x28, 0x09, 0x52, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x22, 0x26, 0x0a, 0x0a, 0x48, 0x65, 0x6c, 0x6c,
0x6f, 0x52, 0x65, 0x70, 0x6c, 0x79, 0x12, 0x18, 0x0a, 0x07, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67,
0x65, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x52, 0x07, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65,
0x32, 0x3f, 0x0a, 0x07, 0x47, 0x72, 0x65, 0x65, 0x74, 0x65, 0x72, 0x12, 0x34, 0x0a, 0x08, 0x53,
0x61, 0x79, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x12, 0x13, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e,
0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x1a, 0x11, 0x2e, 0x70,
0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x52, 0x65, 0x70, 0x6c, 0x79, 0x22,
0x00, 0x42, 0x67, 0x0a, 0x1b, 0x69, 0x6f, 0x2e, 0x67, 0x72, 0x70, 0x63, 0x2e, 0x65, 0x78, 0x61,
0x6d, 0x70, 0x6c, 0x65, 0x73, 0x2e, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x77, 0x6f, 0x72, 0x6c, 0x64,
0x42, 0x0f, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x57, 0x6f, 0x72, 0x6c, 0x64, 0x50, 0x72, 0x6f, 0x74,
0x6f, 0x50, 0x01, 0x5a, 0x35, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61,
0x6e, 0x67, 0x2e, 0x6f, 0x72, 0x67, 0x2f, 0x67, 0x72, 0x70, 0x63, 0x2f, 0x65, 0x78, 0x61, 0x6d,
0x70, 0x6c, 0x65, 0x73, 0x2f, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x77, 0x6f, 0x72, 0x6c, 0x64, 0x2f,
0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x77, 0x6f, 0x72, 0x6c, 0x64, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74,
0x6f, 0x33,
}
var (
file_helloworld_helloworld_proto_rawDescOnce sync.Once
file_helloworld_helloworld_proto_rawDescData = file_helloworld_helloworld_proto_rawDesc
)
func file_helloworld_helloworld_proto_rawDescGZIP() []byte {
file_helloworld_helloworld_proto_rawDescOnce.Do(func() {
file_helloworld_helloworld_proto_rawDescData = protoimpl.X.CompressGZIP(file_helloworld_helloworld_proto_rawDescData)
})
return file_helloworld_helloworld_proto_rawDescData
}
var file_helloworld_helloworld_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
var file_helloworld_helloworld_proto_goTypes = []interface{}{
(*HelloRequest)(nil), // 0: proto.HelloRequest
(*HelloReply)(nil), // 1: proto.HelloReply
}
var file_helloworld_helloworld_proto_depIdxs = []int32{
0, // 0: proto.Greeter.SayHello:input_type -> proto.HelloRequest
1, // 1: proto.Greeter.SayHello:output_type -> proto.HelloReply
1, // [1:2] is the sub-list for method output_type
0, // [0:1] is the sub-list for method input_type
0, // [0:0] is the sub-list for extension type_name
0, // [0:0] is the sub-list for extension extendee
0, // [0:0] is the sub-list for field type_name
}
func init() { file_helloworld_helloworld_proto_init() }
func file_helloworld_helloworld_proto_init() {
if File_helloworld_helloworld_proto != nil {
return
}
if !protoimpl.UnsafeEnabled {
file_helloworld_helloworld_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
switch v := v.(*HelloRequest); i {
case 0:
return &v.state
case 1:
return &v.sizeCache
case 2:
return &v.unknownFields
default:
return nil
}
}
file_helloworld_helloworld_proto_msgTypes[1].Exporter = func(v interface{}, i int) interface{} {
switch v := v.(*HelloReply); i {
case 0:
return &v.state
case 1:
return &v.sizeCache
case 2:
return &v.unknownFields
default:
return nil
}
}
}
type x struct{}
out := protoimpl.TypeBuilder{
File: protoimpl.DescBuilder{
GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
RawDescriptor: file_helloworld_helloworld_proto_rawDesc,
NumEnums: 0,
NumMessages: 2,
NumExtensions: 0,
NumServices: 1,
},
GoTypes: file_helloworld_helloworld_proto_goTypes,
DependencyIndexes: file_helloworld_helloworld_proto_depIdxs,
MessageInfos: file_helloworld_helloworld_proto_msgTypes,
}.Build()
File_helloworld_helloworld_proto = out.File
file_helloworld_helloworld_proto_rawDesc = nil
file_helloworld_helloworld_proto_goTypes = nil
file_helloworld_helloworld_proto_depIdxs = nil
}
helloworld_grpc.pb.go
// Code generated by protoc-gen-go-grpc. DO NOT EDIT.
// versions:
// - protoc-gen-go-grpc v1.2.0
// - protoc v4.22.0
// source: helloworld/helloworld.proto
package helloworld
import (
context "context"
grpc "google.golang.org/grpc"
codes "google.golang.org/grpc/codes"
status "google.golang.org/grpc/status"
)
// This is a compile-time assertion to ensure that this generated file
// is compatible with the grpc package it is being compiled against.
// Requires gRPC-Go v1.32.0 or later.
const _ = grpc.SupportPackageIsVersion7
// GreeterClient is the client API for Greeter service.
//
// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream.
type GreeterClient interface {
// Sends a greeting
SayHello(ctx context.Context, in *HelloRequest, opts ...grpc.CallOption) (*HelloReply, error)
}
type greeterClient struct {
cc grpc.ClientConnInterface
}
func NewGreeterClient(cc grpc.ClientConnInterface) GreeterClient {
return &greeterClient{cc}
}
func (c *greeterClient) SayHello(ctx context.Context, in *HelloRequest, opts ...grpc.CallOption) (*HelloReply, error) {
out := new(HelloReply)
err := c.cc.Invoke(ctx, "/proto.Greeter/SayHello", in, out, opts...)
if err != nil {
return nil, err
}
return out, nil
}
// GreeterServer is the server API for Greeter service.
// All implementations must embed UnimplementedGreeterServer
// for forward compatibility
type GreeterServer interface {
// Sends a greeting
SayHello(context.Context, *HelloRequest) (*HelloReply, error)
mustEmbedUnimplementedGreeterServer()
}
// UnimplementedGreeterServer must be embedded to have forward compatible implementations.
type UnimplementedGreeterServer struct {
}
func (UnimplementedGreeterServer) SayHello(context.Context, *HelloRequest) (*HelloReply, error) {
return nil, status.Errorf(codes.Unimplemented, "method SayHello not implemented")
}
func (UnimplementedGreeterServer) mustEmbedUnimplementedGreeterServer() {}
// UnsafeGreeterServer may be embedded to opt out of forward compatibility for this service.
// Use of this interface is not recommended, as added methods to GreeterServer will
// result in compilation errors.
type UnsafeGreeterServer interface {
mustEmbedUnimplementedGreeterServer()
}
func RegisterGreeterServer(s grpc.ServiceRegistrar, srv GreeterServer) {
s.RegisterService(&Greeter_ServiceDesc, srv)
}
func _Greeter_SayHello_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
in := new(HelloRequest)
if err := dec(in); err != nil {
return nil, err
}
if interceptor == nil {
return srv.(GreeterServer).SayHello(ctx, in)
}
info := &grpc.UnaryServerInfo{
Server: srv,
FullMethod: "/proto.Greeter/SayHello",
}
handler := func(ctx context.Context, req interface{}) (interface{}, error) {
return srv.(GreeterServer).SayHello(ctx, req.(*HelloRequest))
}
return interceptor(ctx, in, info, handler)
}
// Greeter_ServiceDesc is the grpc.ServiceDesc for Greeter service.
// It's only intended for direct use with grpc.RegisterService,
// and not to be introspected or modified (even as a copy)
var Greeter_ServiceDesc = grpc.ServiceDesc{
ServiceName: "proto.Greeter",
HandlerType: (*GreeterServer)(nil),
Methods: []grpc.MethodDesc{
{
MethodName: "SayHello",
Handler: _Greeter_SayHello_Handler,
},
},
Streams: []grpc.StreamDesc{},
Metadata: "helloworld/helloworld.proto",
}
【server側の実装】
//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"
"log"
"net"
"google.golang.org/grpc"
pb "google.golang.org/grpc/examples/helloworld/helloworld"
)
const (
port = ":50051"
)
type server struct{
pb.UnimplementedGreeterServer
}
// SayHelloメソッドを実装
func (s *server) SayHello(ctx context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
log.Printf("Received: %v", in.Name)
return &pb.HelloReply{Message: "Hello " + in.Name}, nil
}
func main() {
// リッスン処理
lis, err := net.Listen("tcp", port)
if err != nil {
log.Fatalf("failed to listen: %v", err)
}
// サーバ起動
s := grpc.NewServer()
pb.RegisterGreeterServer(s, &server{})
if err := s.Serve(lis); err != nil {
log.Fatalf("failed to serve: %v", err)
}
}
【Client側の実装】
// Package main implements a client for Greeter service.
package main
import (
"context"
"log"
"os"
"time"
"google.golang.org/grpc"
pb "google.golang.org/grpc/examples/helloworld/helloworld"
)
const (
address = "localhost:50051"
defaultName = "world"
)
func main() {
// gRPCコネクションの作成
conn, err := grpc.Dial(address, grpc.WithInsecure())
if err != nil {
log.Fatalf("did not connect: %v", err)
}
defer conn.Close()
c := pb.NewGreeterClient(conn)
// 引数の準備
name := defaultName
if len(os.Args) > 1 {
name = os.Args[1]
}
// contextの準備
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
defer cancel()
// SayHelloメソッドの呼び出し
r, err := c.SayHello(ctx, &pb.HelloRequest{Name: name})
if err != nil {
log.Fatalf("could not greet: %v", err)
}
log.Printf("Greeting: %s", r.Message)
}
動作確認
サーバーを動かす
go run greeter_server/main.go
リクエストを実行
go run main.go
2023/02/20 00:19:51 Greeting: Hello world