golang 微服务开发（五）go

代码地址

go micro 简单使用

目录结构 go init go_micro_learn

- proto // 放proto文件
- server.go //微服务服务端
- client.go  // 微服务客户端

使用proto生成文件，生成的包名为pb

syntax = "proto3";
option go_package = "./;pb";

service Greeter {
    rpc Hello(HelloRequest) returns (HelloResponse) {}
}

message HelloRequest {
    string name = 1;
}

message HelloResponse {
    string greeting = 2;
}

使用protoc 生成.go 文件 protoc --proto_path=. --go_out=. --micro_out=. proto/greeter.proto

server端

package main

import (
    "fmt"
    pb "go_micro_learn/proto"

    "context"

    micro "github.com/micro/go-micro/v2"
)

type Greeter struct {
}

func (g *Greeter) Hello(ctx context.Context, req *pb.HelloRequest, res *pb.HelloResponse) error {
    fmt.Println("server")
    res.Greeting = "接收到的值为" + req.Name

    return nil

}

func main() {
    // 创建服务
    service := micro.NewService(
        micro.Name("greeter.server"), // 服务名为greeter.server
        micro.Address("0.0.0.0:9630"),
    )

    // 初始化服务
    service.Init()

    //注册服务 参数1为micro服务
    pb.RegisterGreeterHandler(service.Server(), new(Greeter))

    service.Run()
}

client端

package main

import (
    "context"
    "fmt"
    pb "go_micro_learn/proto"

    micro "github.com/micro/go-micro/v2"
)

func main() {
    service := micro.NewService(micro.Name("geeter.client"))

    service.Init()

    // 创建新客户端
    greeter := pb.NewGreeterService("greeter.server", service.Client()) // 定义要访问的服务

    // 调用服务的Hello方法
    res, err := greeter.Hello(context.Background(), &pb.HelloRequest{
        Name: "abc",
    })
    fmt.Println("res", res)
    fmt.Println(err)

}

遇到的报错

使用grpc报错 etcd client3

报错信息 grpc 版本问题

github.com/coreos/etcd/clientv3/balancer/resolver/endpoint
../../pkg/mod/github.com/coreos/etcd@v3.3.18+incompatible/clientv3/balancer/resolver/endpoint/endpoint.go:114:78: undefined: resolver.BuildOption
../../pkg/mod/github.com/coreos/etcd@v3.3.18+incompatible/clientv3/balancer/resolver/endpoint/endpoint.go:182:31: undefined: resolver.ResolveNowOption
# github.com/coreos/etcd/clientv3/balancer/picker
../../pkg/mod/github.com/coreos/etcd@v3.3.18+incompatible/clientv3/balancer/picker/err.go:37:44: undefined: balancer.PickOptions
../../pkg/mod/github.com/coreos/etcd@v3.3.18+incompatible/clientv3/balancer/picker/roundrobin_balanced.go:55:54: undefined: balancer.PickOptions

解决方案

go mod 中添加
replace google.golang.org/grpc => google.golang.org/grpc v1.26.0