学习一段时间的grpc了，今天简单记录下grpc的使用流程。
在进入今天的分享前，请确保自己已经安装好相关的环境：
- go 1.19
- protoc v3.19.4
- protoc-gen-go v1.28.1
- protoc-gen-go-grpc v1.3.0
1.项目目录结构
如下图显示：
2.proto 文件-接口定义
这里我们以简单的 HelloSerivce 为切入点：
syntax = "proto3"; // 固定语法前缀
option go_package = "."; // 指定生成的go代码在你项目中的导入路径
package pb; // 包名
// 定义服务
service HelloService {
// SayHello 方法
rpc SayHello (HelloRequest) returns (HelloResponse) {}
}
// 请求消息
message HelloRequest {
string name = 1;
}
// 响应消息
message HelloResponse {
string reply = 1;
}
3.生成 pb.go 文件
在定义好接口后，我们就可以生成相关的对应的go代码了：
protoc --go_out=./proto --go-grpc_out=./proto pb/hello.proto
# 命令说明
- --go_out，指定 pb.go 文件生成到的目录
- --go-grpc_out，指定 grpc.pb.go 文件生成到的目录
- pb/hello.proto，指定用到的接口定义文件
一键生成后，可以看看相关的 pb.go文件：
hello.pb.go
// Code generated by protoc-gen-go. DO NOT EDIT.
// versions:
// protoc-gen-go v1.28.1
// protoc v3.19.4
// source: pb/hello.proto
package proto
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)
)
// 请求消息
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_pb_hello_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_pb_hello_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_pb_hello_proto_rawDescGZIP(), []int{0}
}
func (x *HelloRequest) GetName() string {
if x != nil {
return x.Name
}
return ""
}
// 响应消息
type HelloResponse struct {
state protoimpl.MessageState
sizeCache protoimpl.SizeCache
unknownFields protoimpl.UnknownFields
Reply string `protobuf:"bytes,1,opt,name=reply,proto3" json:"reply,omitempty"`
}
func (x *HelloResponse) Reset() {
*x = HelloResponse{}
if protoimpl.UnsafeEnabled {
mi := &file_pb_hello_proto_msgTypes[1]
ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
ms.StoreMessageInfo(mi)
}
}
func (x *HelloResponse) String() string {
return protoimpl.X.MessageStringOf(x)
}
func (*HelloResponse) ProtoMessage() {}
func (x *HelloResponse) ProtoReflect() protoreflect.Message {
mi := &file_pb_hello_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 HelloResponse.ProtoReflect.Descriptor instead.
func (*HelloResponse) Descriptor() ([]byte, []int) {
return file_pb_hello_proto_rawDescGZIP(), []int{1}
}
func (x *HelloResponse) GetReply() string {
if x != nil {
return x.Reply
}
return ""
}
var File_pb_hello_proto protoreflect.FileDescriptor
var file_pb_hello_proto_rawDesc = []byte{
0x0a, 0x0e, 0x70, 0x62, 0x2f, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f,
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0x28, 0x09, 0x52, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x22, 0x25, 0x0a, 0x0d, 0x48, 0x65, 0x6c, 0x6c,
0x6f, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e, 0x73, 0x65, 0x12, 0x14, 0x0a, 0x05, 0x72, 0x65, 0x70,
0x6c, 0x79, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x52, 0x05, 0x72, 0x65, 0x70, 0x6c, 0x79, 0x32,
0x41, 0x0a, 0x0c, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x53, 0x65, 0x72, 0x76, 0x69, 0x63, 0x65, 0x12,
0x31, 0x0a, 0x08, 0x53, 0x61, 0x79, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x12, 0x10, 0x2e, 0x70, 0x62,
0x2e, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x1a, 0x11, 0x2e,
0x70, 0x62, 0x2e, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e, 0x73, 0x65,
0x22, 0x00, 0x42, 0x03, 0x5a, 0x01, 0x2e, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
}
var (
file_pb_hello_proto_rawDescOnce sync.Once
file_pb_hello_proto_rawDescData = file_pb_hello_proto_rawDesc
)
func file_pb_hello_proto_rawDescGZIP() []byte {
file_pb_hello_proto_rawDescOnce.Do(func() {
file_pb_hello_proto_rawDescData = protoimpl.X.CompressGZIP(file_pb_hello_proto_rawDescData)
})
return file_pb_hello_proto_rawDescData
}
var file_pb_hello_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
var file_pb_hello_proto_goTypes = []interface{}{
(*HelloRequest)(nil), // 0: pb.HelloRequest
(*HelloResponse)(nil), // 1: pb.HelloResponse
}
var file_pb_hello_proto_depIdxs = []int32{
0, // 0: pb.HelloService.SayHello:input_type -> pb.HelloRequest
1, // 1: pb.HelloService.SayHello:output_type -> pb.HelloResponse
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_pb_hello_proto_init() }
func file_pb_hello_proto_init() {
if File_pb_hello_proto != nil {
return
}
if !protoimpl.UnsafeEnabled {
file_pb_hello_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_pb_hello_proto_msgTypes[1].Exporter = func(v interface{}, i int) interface{} {
switch v := v.(*HelloResponse); 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_pb_hello_proto_rawDesc,
NumEnums: 0,
NumMessages: 2,
NumExtensions: 0,
NumServices: 1,
},
GoTypes: file_pb_hello_proto_goTypes,
DependencyIndexes: file_pb_hello_proto_depIdxs,
MessageInfos: file_pb_hello_proto_msgTypes,
}.Build()
File_pb_hello_proto = out.File
file_pb_hello_proto_rawDesc = nil
file_pb_hello_proto_goTypes = nil
file_pb_hello_proto_depIdxs = nil
}
hello_grpc.pb.go
// Code generated by protoc-gen-go-grpc. DO NOT EDIT.
// versions:
// - protoc-gen-go-grpc v1.3.0
// - protoc v3.19.4
// source: pb/hello.proto
package proto
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
const (
HelloService_SayHello_FullMethodName = "/pb.HelloService/SayHello"
)
// HelloServiceClient is the client API for HelloService 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 HelloServiceClient interface {
// SayHello 方法
SayHello(ctx context.Context, in *HelloRequest, opts ...grpc.CallOption) (*HelloResponse, error)
}
type helloServiceClient struct {
cc grpc.ClientConnInterface
}
func NewHelloServiceClient(cc grpc.ClientConnInterface) HelloServiceClient {
return &helloServiceClient{cc}
}
func (c *helloServiceClient) SayHello(ctx context.Context, in *HelloRequest, opts ...grpc.CallOption) (*HelloResponse, error) {
out := new(HelloResponse)
err := c.cc.Invoke(ctx, HelloService_SayHello_FullMethodName, in, out, opts...)
if err != nil {
return nil, err
}
return out, nil
}
// HelloServiceServer is the server API for HelloService service.
// All implementations must embed UnimplementedHelloServiceServer
// for forward compatibility
type HelloServiceServer interface {
// SayHello 方法
SayHello(context.Context, *HelloRequest) (*HelloResponse, error)
mustEmbedUnimplementedHelloServiceServer()
}
// UnimplementedHelloServiceServer must be embedded to have forward compatible implementations.
type UnimplementedHelloServiceServer struct {
}
func (UnimplementedHelloServiceServer) SayHello(context.Context, *HelloRequest) (*HelloResponse, error) {
return nil, status.Errorf(codes.Unimplemented, "method SayHello not implemented")
}
func (UnimplementedHelloServiceServer) mustEmbedUnimplementedHelloServiceServer() {}
// UnsafeHelloServiceServer may be embedded to opt out of forward compatibility for this service.
// Use of this interface is not recommended, as added methods to HelloServiceServer will
// result in compilation errors.
type UnsafeHelloServiceServer interface {
mustEmbedUnimplementedHelloServiceServer()
}
func RegisterHelloServiceServer(s grpc.ServiceRegistrar, srv HelloServiceServer) {
s.RegisterService(&HelloService_ServiceDesc, srv)
}
func _HelloService_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.(HelloServiceServer).SayHello(ctx, in)
}
info := &grpc.UnaryServerInfo{
Server: srv,
FullMethod: HelloService_SayHello_FullMethodName,
}
handler := func(ctx context.Context, req interface{}) (interface{}, error) {
return srv.(HelloServiceServer).SayHello(ctx, req.(*HelloRequest))
}
return interceptor(ctx, in, info, handler)
}
// HelloService_ServiceDesc is the grpc.ServiceDesc for HelloService service.
// It's only intended for direct use with grpc.RegisterService,
// and not to be introspected or modified (even as a copy)
var HelloService_ServiceDesc = grpc.ServiceDesc{
ServiceName: "pb.HelloService",
HandlerType: (*HelloServiceServer)(nil),
Methods: []grpc.MethodDesc{
{
MethodName: "SayHello",
Handler: _HelloService_SayHello_Handler,
},
},
Streams: []grpc.StreamDesc{},
Metadata: "pb/hello.proto",
}
4.server
此段我们主要是定义 service 的具体业务处理逻辑，启动 grpc server。
server
package main
import (
"context"
"fmt"
"log"
"net
"go-grpc-demo1/proto"
"google.golang.org/grpc"
)
func main() {
// create tcp lis
lis, err := net.Listen("tcp", ":8093")
if err != nil {
panic(err)
}
// create grpc server
server := grpc.NewServer()
// register user defined service
log.Printf("Register server service: %+v", HelloService{})
proto.RegisterHelloServiceServer(server, &HelloService{})
// run grpc server
if err = server.Serve(lis); err != nil {
panic(err)
}
}
// 具体业务处理
type HelloService struct {
proto.UnimplementedHelloServiceServer
}
// 具体业务实现的方法逻辑
func (s *HelloService) SayHello(ctx context.Context, req *proto.HelloRequest) (*proto.HelloResponse, error) {
log.Printf("Recv from RPC Client call, params: %s", req.Name)
return &proto.HelloResponse{
Reply: fmt.Sprintf("hello name: %s", req.Name),
}, nil
}
写好 server 后可以启动服务，等待client的连接、请求。
5.client
客户端代码很简单，此段代码主要根据 pb.go、grpc.pb.go 创建 client，进行server的 Dial 请求：
package main
import (
"context"
"fmt"
"log"
"go-grpc-demo1/proto"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials/insecure"
)
func main() {
// conn server
conn, err := grpc.Dial("localhost:8093", grpc.WithTransportCredentials(insecure.NewCredentials()))
if err != nil {
log.Fatalln(err)
}
// call .grpc.pb.go -> NewClient(), create client
client := proto.NewHelloServiceClient(conn)
// call .grpc.pb.go client req method, use .pb.go file pre generate req method
resp, err := client.SayHello(context.Background(), &proto.HelloRequest{
Name: "gRPC_hello",
})
// print response params
fmt.Printf("response: %+v", resp)
}
6.测试请求响应
先启动 server, 然后启动 client 向server发起请求：
server
2023/03/20 15:07:19 Register server service: {UnimplementedHelloServiceServer:{}}
client
response: reply:"hello name: gRPC_hello"
server
2023/03/20 15:07:19 Register server service: {UnimplementedHelloServiceServer:{}}
2023/03/20 15:08:05 Recv from RPC Client call, params: gRPC_hello
从我们定义的接口及 server 和 client 的请求响应逻辑，我们向 server 端发送带 name 参数的请求，server 端收到后打印请求参数，并返回 reply 响应，整个流程简单，但不失为go-grpc入门实操的一次尝试，更复杂的业务逻辑，更多服务治理，无非就是加功能，但这些基本流程是一样的，动起手来实践吧。
参考文档：
标签：proto,gRPC,pb,grpc,实操,go,hello,protoimpl From： https://www.cnblogs.com/davis12/p/17236399.html