使用twirp搭建rpc框架

1.安装protobuf complier

链接:https://pan.baidu.com/s/1HcCTttxZHJYopu-YwUl6PQ 提取码:3rub

把下载好的protoc.exe文件放到你的$GOPATH/bin下，并且保证你的$GOPATH/bin目录已经导入到环境变量中

2.安装protoc-gen-go

到https://github.com/golang/protobuf 把库文件克隆下来，再执行下面的命令生成protoc-gen-go.exe到$GOPATH/bin中

go get -u github.com/golang/protobuf/protoc-gen-go

3.安装protoc-gen-twirp

到https://github.com/twitchtv/twirp 把库文件克隆下来，再执行下面的命令生成protoc-gen-twirp.exe到$GOPATH/bin中

go get -u github.com/twitchtv/twirp/protoc-gen-twirp

4.编写protobuf服务的定义

在刚刚克隆下来的twitch文件夹下创建一个twirpexample文件夹，在twirpexample文件夹下创建rpc/haberdasher/service.proto，编写service.proto

syntax = "proto3";

package twirp.example.haberdasher;
option go_package = "haberdasher";

// Haberdasher service makes hats for clients.
service Haberdasher {
  // MakeHat produces a hat of mysterious, randomly-selected color!
  rpc MakeHat(Size) returns (Hat);
}

// Size of a Hat, in inches.
message Size {
  int32 inches = 1; // must be > 0
}

// A Hat is a piece of headwear made by a Haberdasher.
message Hat {
  int32 inches = 1;
  string color = 2; // anything but "invisible"
  string name = 3; // i.e. "bowler"
}

5.生成*.pb.go和*.twirp.go

切换到rpc目录，执行下面的命令

protoc --go_out=.  --proto_path=. ./rpc/haberdasher/service.proto --twirp_out=.

解释一下，--go_out就是生成的*.pb.go文件存放的位置，--proto_path就是待转换的*.proto文件存放的位置，--twirp_out就是生成的*.twirp.go文件存放的位置

6.实现服务器的业务逻辑(接口的方法)

在twirpexample文件夹下，创建internal/haberdasherserver/server.go，编写server.go

package haberdasherserver

import (
    "context"
    "math/rand"

    "github.com/twitchtv/twirp"
    pb "github.com/twitchtv/twirpexample/rpc/haberdasher"
)

// Server implements the Haberdasher service
type Server struct {}

func (s *Server) MakeHat(ctx context.Context, size *pb.Size) (hat *pb.Hat, err error) {
    if size.Inches <= 0 {
        return nil, twirp.InvalidArgumentError("inches", "I can't make a hat that small!")
    }
    return &pb.Hat{
        Inches:  size.Inches,
        Color: []string{"white", "black", "brown", "red", "blue"}[rand.Intn(4)],
        Name:  []string{"bowler", "baseball cap", "top hat", "derby"}[rand.Intn(3)],
    }, nil
}

7.创建提供服务的服务器

在twirpexample文件夹下，创建cmd/server/main.go，编写main.go

package main

import (
    "net/http"

    "github.com/twitchtv/twirpexample/internal/haberdasherserver"
    "github.com/twitchtv/twirpexample/rpc/haberdasher"
)

func main() {
  server := &haberdasherserver.Server{} // implements Haberdasher interface
  twirpHandler := haberdasher.NewHaberdasherServer(server, nil)

  http.ListenAndServe(":8080", twirpHandler)
}

8.创建客户端

在twirpexample文件夹下，创建cmd/client/main.go，编写main.go

package main

import (
    "context"
    "net/http"
    "os"
    "fmt"
    "github.com/twitchtv/twirpexample/rpc/haberdasher"
)

func main() {
    client := haberdasher.NewHaberdasherProtobufClient("http://localhost:8080", &http.Client{})

    hat, err := client.MakeHat(context.Background(), &haberdasher.Size{Inches: 12})
    if err != nil {
        fmt.Printf("oh no: %v", err)
        os.Exit(1)
    }
    fmt.Printf("I have a nice new hat: %+v", hat)
}

9.测试

在cmd/server/main.go中执行go run main.go开启服务器，在cmd/client/main.go中执行go run main.go开启客户端访问相应的服务