【笔记】gRPC-Gateway学习笔记

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前言

gRPC-Gateway is a plugin of protoc. It reads a gRPC service definition and generates a reverse-proxy server which translates a RESTful JSON API into gRPC. This server is generated according to custom options in your gRPC definition.（官网）

下载依赖

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go install github.com/grpc-ecosystem/grpc-gateway/v2/protoc-gen-grpc-gateway@latest
go install google.golang.org/protobuf/cmd/protoc-gen-go@latest
go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@latest

下载Google提供的Protobuf

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mkdir -p google/api
cd google/api
wget https://raw.githubusercontent.com/googleapis/googleapis/master/google/api/annotations.proto
wget https://raw.githubusercontent.com/googleapis/googleapis/master/google/api/http.proto
cd ../..
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+ google
  + api
    - annotations.proto
    - http.proto

创建基本的GRPC结构

client/main.go
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package main

import (
	"context"
	"fmt"
	"github.com/feiju12138/grpc/test"
	"google.golang.org/grpc"
)

func main() {
	listen, _ := grpc.Dial("127.0.0.1:8888", grpc.WithInsecure())
	client := test.NewTestServiceClient(listen)
	res, _ := client.Test(context.Background(), &test.Req{Message: "1"})
	fmt.Println(res.GetMessage())
}
service/main.go
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package main

import (
	"context"
	"github.com/feiju12138/grpc/test"
	"google.golang.org/grpc"
	"net"
)

type TestService struct {
	test.UnimplementedTestServiceServer
}

func (*TestService) Test(context context.Context, req *test.Req) (*test.Res, error) {
	return &test.Res{Message: req.GetMessage()}, nil
}

func main() {
	listen, _ := net.Listen("tcp", "0.0.0.0:8888")
	server := grpc.NewServer()
	test.RegisterTestServiceServer(server, &TestService{})
	server.Serve(listen)
}
test/test.proto
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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

package test;

message Req {
  string message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res);
}

在Protobuf的service中添加option

test/test.proto
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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

import "google/api/annotations.proto";

package test;

message Req {
  string message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res) {
    option(google.api.http) = {
      post:"/api/test",
      body:"*",
    };
  };
}

GRPC生成Go代码

-I ./proto：指定项目根目录的所在路径
--go_out ./、--go-grpc_out ./、--grpc-gateway_out .：指定相对于项目根目录的路径
./test/test.proto：Protobuf的所在路径

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protoc -I ./ \
  --go_out ./ --go_opt paths=source_relative \ 
  --go-grpc_out ./ --go-grpc_opt paths=source_relative \ 
  --grpc-gateway_out ./ --grpc-gateway_opt paths=source_relative \
  ./test/test.proto
  • 会在Protobuf文件同级目录下生成test.pb.go、test.pb.gw.go、test_grpc.pb.go文件

在服务端添加对外暴露的代码

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package main

import (
	"context"
	"github.com/feiju12138/grpc/test"
	"github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
	"google.golang.org/grpc"
	"net"
	"net/http"
	"sync"
)

type TestService struct {
	test.UnimplementedTestServiceServer
}

func (*TestService) Test(context context.Context, req *test.Req) (*test.Res, error) {
	return &test.Res{Message: req.GetMessage() + "0"}, nil
}

func registerGateway(waitGroup *sync.WaitGroup) {
	// 创建中间层
	conn, _ := grpc.DialContext(context.Background(), "127.0.0.1:8888", grpc.WithBlock(), grpc.WithInsecure())
	mux := runtime.NewServeMux()
	// 创建http服务
	gatewayServer := &http.Server{
		Handler: mux,
		Addr:    "0.0.0.0:8889",
	}
	// 启动网关服务
	gatewayServer.ListenAndServe()
	// 注册网关
	test.RegisterTestServiceHandler(context.Background(), mux, conn)
	waitGroup.Done()
}

func registerGRPC(waitGroup *sync.WaitGroup) {
	listen, _ := net.Listen("tcp", "0.0.0.0:8888")
	server := grpc.NewServer()
	test.RegisterTestServiceServer(server, &TestService{})
	server.Serve(listen)
	waitGroup.Done()
}

func main() {
	waitGroup := sync.WaitGroup{}
	waitGroup.Add(2)
	go registerGateway(&waitGroup)
	go registerGRPC(&waitGroup)
	waitGroup.Wait()
}

GRPCGateway配置

处理GET请求

request
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GET http://127.0.0.1:8080/api/test?message=1
Accept: application/json

请求参数映射为字符串

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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

import "google/api/annotations.proto";

package test;

message Req {
  string message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res) {
    option(google.api.http) = {
      get:"/api/test",
    };
  };
}

请求参数映射为结构体

request
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GET http://127.0.0.1:8080/api/test?message.key=1
Accept: application/json
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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

import "google/api/annotations.proto";

package test;

message Message {
  string key = 1
}

message Req {
  Message message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res) {
    option(google.api.http) = {
      get:"/api/test",
    };
  };
}

处理POST请求

请求参数映射为字符串

从query获取数据
request
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POST http://127.0.0.1:8080/api/test?message=1
Accept: application/json
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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

import "google/api/annotations.proto";

package test;

message Req {
  string message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res) {
    option(google.api.http) = {
      post:"/api/test",
      body:"*",
    };
  };
}
从body获取数据
request
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POST http://127.0.0.1:8080/api/test
Accept: application/json

"1"
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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

import "google/api/annotations.proto";

package test;

message Req {
  string message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res) {
    option(google.api.http) = {
      post:"/api/test",
      body:"*",
    };
  };
}
从path获取数据
request
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POST http://127.0.0.1:8080/api/test/1
Accept: application/json
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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

import "google/api/annotations.proto";

package test;

message Req {
  string message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res) {
    option(google.api.http) = {
      post:"/api/test/{message}",
      body:"*",
    };
  };
}

请求参数映射为结构体

从query获取数据
request
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POST http://127.0.0.1:8080/api/test?message.key=1
Accept: application/json
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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

import "google/api/annotations.proto";

package test;

message Message {
  string key = 1
}

message Req {
  Message message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res) {
    option(google.api.http) = {
      post:"/api/test",
      body:"message",
    };
  };
}
从body获取数据
request
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POST http://127.0.0.1:8080/api/test
Accept: application/json

{"key": "value"}
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syntax = "proto3";

option go_package="github.com/feiju12138/grpc/test;test";

import "google/api/annotations.proto";

package test;

message Message {
  string key = 1
}

message Req {
  Message message = 1;
}

message Res {
  string message = 1;
}

service TestService {
  rpc Test(Req) returns (Res) {
    option(google.api.http) = {
      post:"/api/test",
      body:"message",
    };
  };
}

完成

参考文献

Github——go圈里最会写js的奇淼