eureka

README

registry-eureka (This is a community driven project)

registry-eureka implements Hertz registry and resolver for Netflix Eureka.

How to use?

Server

example/server/main.go

package main

import (
	"context"
	"time"

	"github.com/cloudwego/hertz/pkg/app"
	"github.com/cloudwego/hertz/pkg/app/server"
	"github.com/cloudwego/hertz/pkg/app/server/registry"
	"github.com/cloudwego/hertz/pkg/common/utils"
	"github.com/cloudwego/hertz/pkg/protocol/consts"
	"github.com/hertz-contrib/registry/eureka"
)

func main() {
	addr := "127.0.0.1:8888"
	r := eureka.NewEurekaRegistry([]string{"http://127.0.0.1:8761/eureka"}, 40*time.Second)
	h := server.Default(
		server.WithHostPorts(addr),
		server.WithRegistry(r, &registry.Info{
			ServiceName: "hertz.discovery.eureka",
			Addr:        utils.NewNetAddr("tcp", addr),
			Weight:      10,
			Tags:        nil,
		}))
	h.GET("/ping", func(c context.Context, ctx *app.RequestContext) {
		ctx.JSON(consts.StatusOK, utils.H{"ping": "pong2"})
	})
	h.Spin()
}

Client

example/client/main.go

package main

import (
	"context"

	"github.com/cloudwego/hertz/pkg/app/client"
	"github.com/cloudwego/hertz/pkg/app/middlewares/client/sd"
	"github.com/cloudwego/hertz/pkg/common/config"
	"github.com/cloudwego/hertz/pkg/common/hlog"
	"github.com/hertz-contrib/registry/eureka"
)

func main() {
	cli, err := client.NewClient()
	if err != nil {
		hlog.Fatal(err)
		return
	}
	r := eureka.NewEurekaResolver([]string{"http://127.0.0.1:8761/eureka"})

	cli.Use(sd.Discovery(r))
	for i := 0; i < 10; i++ {
		status, body, err := cli.Get(context.Background(), nil, "http://hertz.discovery.eureka/ping", config.WithSD(true))
		if err != nil {
			hlog.Fatal(err)
		}
		hlog.Infof("code=%d,body=%s", status, string(body))
	}
}

How to Run example?

Start Eureka Server

docker-compose up

Run Server

go run ./example/server/main.go

Run Client

go run ./example/client/main.go

2022/08/28 22:16:59 Getting app hertz.discovery.eureka from url http://127.0.0.1:8761/eureka/apps/hertz.discovery.eureka
2022/08/28 22:16:59 Got eureka response from url=http://127.0.0.1:8761/eureka/apps/hertz.discovery.eureka
2022/08/28 22:16:59.443078 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.443258 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.443405 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.443548 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.443697 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.443855 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.444004 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.444149 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.444289 main.go:41: [Info] code=200,body={"ping":"pong2"}
2022/08/28 22:16:59.444405 main.go:41: [Info] code=200,body={"ping":"pong2"}

Configuration

This project uses fargo as eureka client. You should refer to fargo documentation for advanced configuration.

There are multiple ways to crate a eurekaRegistry.

• NewEurekaRegistry creates a registry with a slice of eureka server addresses.
• NewEurekaRegistryFromConfig creates a registry with given fargo.Config.
• NewEurekaRegistryFromConn creates a registry using existing fargo.EurekaConnection .

The same also applies for eurekaResolver.

• NewEurekaResolver creates a resolver with a slice of eureka server addresses.
• NewEurekaResolverFromConfig creates a resolver with given fargo.Config.
• NewEurekaResolverFromConn creates a resolver using existing fargo.EurekaConnection .

Authentication

A straight-forward approach is passing credentials in uri e.g. []string{"http://username:password@127.0.0.1:8080/eureka". Alternatively, you can pass existing connection to NewEurekaRegistryFromConn or NewEurekaResolverFromConn.

Setting Log Level

As discussed above, this project uses fargo as eureka client, which relies on go-logging for logging. Unfortunately, go-logging does not provide an interface to adjust log level. The following code demonstrates how to set log level.

package main

import (
	"context"
	"github.com/op/go-logging"
	"time"

	"github.com/cloudwego/hertz/pkg/app"
	"github.com/cloudwego/hertz/pkg/app/server"
	"github.com/cloudwego/hertz/pkg/app/server/registry"
	"github.com/cloudwego/hertz/pkg/common/utils"
	"github.com/cloudwego/hertz/pkg/protocol/consts"
	"github.com/hertz-contrib/registry/eureka"
)

func main() {

	logging.SetLevel(logging.WARNING, "fargo")
	// set this to a higher level if you wish to check responses from eureka 
	logging.SetLevel(logging.WARNING, "fargo.metadata")
	logging.SetLevel(logging.WARNING, "fargo.marshal")

	addr := "127.0.0.1:8888"
	r := eureka.NewEurekaRegistry([]string{"http://127.0.0.1:8761/eureka"}, 40*time.Second)
	h := server.Default(
		server.WithHostPorts(addr),
		server.WithRegistry(r, &registry.Info{
			ServiceName: "hertz.discovery.eureka",
			Addr:        utils.NewNetAddr("tcp", addr),
			Weight:      10,
			Tags:        nil,
		}))
	h.GET("/ping", func(c context.Context, ctx *app.RequestContext) {
		ctx.JSON(consts.StatusOK, utils.H{"ping": "pong2"})
	})
	h.Spin()
}

Compatibility

This project is compatible with eureka server v1.

Documentation

Index

• Constants
• Variables
• func NewEurekaRegistry(servers []string, heatBeatInterval time.Duration) *eurekaRegistry
• func NewEurekaRegistryFromConfig(config fargo.Config, heatBeatInterval time.Duration) *eurekaRegistry
• func NewEurekaRegistryFromConn(conn fargo.EurekaConnection, heatBeatInterval time.Duration) *eurekaRegistry
• func NewEurekaResolver(servers []string) *eurekaResolver
• func NewEurekaResolverFromConfig(config fargo.Config) *eurekaResolver
• func NewEurekaResolverFromConn(conn fargo.EurekaConnection) *eurekaResolver
• type RegistryEntity

Constants

const (
	Eureka = "eureka"
	TCP    = "tcp"
	Meta   = "meta"
)

Variables

var (
	ErrNilInfo          = errors.New("registry info can't be nil")
	ErrNilAddr          = errors.New("registry addr can't be nil")
	ErrEmptyServiceName = errors.New("registry service name can't be empty")
	ErrMissingPort      = errors.New("addr missing port")
)

Functions

func NewEurekaRegistry

func NewEurekaRegistry(servers []string, heatBeatInterval time.Duration) *eurekaRegistry

NewEurekaRegistry creates a eureka registry.

func NewEurekaRegistryFromConfig

func NewEurekaRegistryFromConfig(config fargo.Config, heatBeatInterval time.Duration) *eurekaRegistry

NewEurekaRegistryFromConfig creates a eureka registry.

func NewEurekaRegistryFromConn

func NewEurekaRegistryFromConn(conn fargo.EurekaConnection, heatBeatInterval time.Duration) *eurekaRegistry

NewEurekaRegistryFromConn creates a eureka registry.

func NewEurekaResolver

func NewEurekaResolver(servers []string) *eurekaResolver

NewEurekaResolver creates a eureka resolver with a slice of server addresses.

func NewEurekaResolverFromConfig

func NewEurekaResolverFromConfig(config fargo.Config) *eurekaResolver

NewEurekaResolverFromConfig creates a eureka resolver with given configuration.

func NewEurekaResolverFromConn

func NewEurekaResolverFromConn(conn fargo.EurekaConnection) *eurekaResolver

NewEurekaResolverFromConn creates a eureka resolver using an existing connection.

Types

type RegistryEntity

type RegistryEntity struct {
	Weight int
	Tags   map[string]string
}