kratos discovery

常见的微服务注册中心

• consul
• etcd
• zookeeper
• Eureka
• kratos(discovery)

discovery

安装

源码安装

• github
• 下载生成可执行文件

git clone https://github.com/bilibili/discovery.git
cd discovery/cmd/discovery
go build

• 启动 ./discovery -conf discovery-example.toml -alsologtostderr

生成 docker images

docker build -t cc360428/discovery:latest .

docker 安装

docker run -itd --name disvoery -p 7171:7171 lichaocheng/discovery

注册

使用 kraots 之前 set DISCOVERY_NODES=127.0.0.1:7171

package main

import (
	"context"
	"flag"
	"github.com/go-kratos/kratos/pkg/conf/env"
	"github.com/go-kratos/kratos/pkg/conf/paladin"
	"github.com/go-kratos/kratos/pkg/naming"
	"github.com/go-kratos/kratos/pkg/naming/discovery"
	"github.com/go-kratos/kratos/pkg/net/rpc/warden/resolver"
	"im_square/internal/dao"
	"im_square/internal/di"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/go-kratos/kratos/pkg/log"
)

func main() {
	flag.Parse()
	log.Init(&log.Config{Stdout: true}) // debug flag: log.dir={path}
	defer log.Close()
	log.Info("im_square start")
	_ = paladin.Init()
	resolver.Register(discovery.Builder())
	_, closeFunc, err := di.InitApp()
	if err != nil {
		panic(err)
	}
	//consul 注册发现
	var RegCancel context.CancelFunc
	if _gRPCAddr != "" {
		hn, _ := os.Hostname()
		dis := discovery.New(nil)
		ins := &naming.Instance{
			Zone:     env.Zone,
			Env:      env.DeployEnv,
			AppID:    env.AppID,
			Hostname: hn,
			Addrs: []string{
				"grpc://" + _gRPCAddr,
			},
		}
		if cancel, err := dis.Register(context.Background(), ins); err != nil {
			panic(err)
		} else {
			RegCancel = cancel
		}
	}
	c := make(chan os.Signal, 1)
	signal.Notify(c, syscall.SIGHUP, syscall.SIGQUIT, syscall.SIGTERM, syscall.SIGINT)
	for {
		s := <-c
		log.Info("get a signal %s", s.String())
		switch s {
		case syscall.SIGQUIT, syscall.SIGTERM, syscall.SIGINT:
			closeFunc()
			RegCancel()
			log.Info("main exit")
			time.Sleep(time.Second)
			return
		case syscall.SIGHUP:
		default:
			return
		}
	}
}

var _gRPCAddr string

func init() {
	addFlag(flag.CommandLine)
	dao.SynchronizationRedisAll()
}

func addFlag(fs *flag.FlagSet) {
	v := os.Getenv("DISCOVERY_GRPC_ADDR")
	fs.StringVar(&_gRPCAddr, "grpc.addr", v, "app listen grpc port, default: nil")
}

发现

发现方式两种：1、直接连接输入 服务端 IP 地址；2、通过 discovery 注册中心（或其他的注册中心）

• 获取要发现的服务的 proto 文件生成对应的 pd 文件
• 设置 discovery 节点地址
• client 代码

1. 通过 discovery 注册中心连接

const AppID = "square_recom_ai_v1"

//  new grpc client
func NewAiRecomClient(cfg *warden.ClientConfig, opts ...grpc.DialOption) (SquareRecomAiClient, error) {
	client := warden.NewClient(cfg, opts...)
	cc, err := client.Dial(context.Background(), fmt.Sprintf("discovery://default/%s", AppID))
	if err != nil {
		log.Error("square_recom_ai_error", err.Error())
		return nil, err
		//return nil, nil
	}
	log.Info("square_recom_ai like ok")
	return NewSquareRecomAiClient(cc), nil
}

1. 已知服务 IP 地址

// NewImSquareClient new grpc client
func NewAiRecomClient(cfg *warden.ClientConfig, opts ...grpc.DialOption) (SquareRecomAiClient, error) {
	client := warden.NewClient(cfg, opts...)
	cc, err := client.Dial(context.Background(), fmt.Sprintf("direct://default/127.0.0.1:9003"))

	if err != nil {
		log.Error("square_recom_ai_error", err.Error())
		return nil, err
		//return nil, nil
	}
	log.Info("square_recom_ai like ok")
	return NewSquareRecomAiClient(cc), nil
}