eureka

Service Registration and Discovery eureka Extensions provided by Hertz.

Install

go get github.com/hertz-contrib/eureka

Service Registry

NewEurekaRegistry

NewEurekaRegistry uses eureka to create a new service registry, you need to pass the service Url into NewConn through a string slice, and also pass in the heartbeat interval.

Function signature:

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

Example:

func main() {
    // ...
    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,
        }))
    //...
}

NewEurekaRegistryFromConfig

NewEurekaRegistryFromConfig uses eureka to create a new service registry, you need to pass in the configuration and call NewConnFromConfig , and also need to pass in the heartbeat interval.

Function signature:

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

Example:

func main() {
    // ...
    config := fargo.Config{
    // ...
    }
    r := eureka.NewEurekaRegistryFromConfig(config, 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,
        }))
    //...
}

NewEurekaRegistryFromConn

NewEurekaRegistryFromConn uses eureka to create a new service registry, you need to pass in conn directly, and also need to pass in the heartbeat interval.

Function signature:

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

Example:

func main() {
    // ...
    conn := fargo.EurekaConnection{
    // ...
    }
    r := eureka.NewEurekaRegistryFromConn(conn, 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,
        }))
    //...
}

Service Discovery

NewEurekaResolver

NewEurekaResolver uses eureka to create a new service discovery center, you need to pass the service Url through a string slice to NewConn.

Function signature:

func NewEurekaResolver(servers []string) *eurekaResolver

Example:

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))
    // ...
}

NewEurekaResolverFromConfig

NewEurekaResolverFromConfig uses eureka to create a new service discovery center, requires passing in the configuration and calling NewConnFromConfig.

Function signature:

func NewEurekaResolverFromConfig(config fargo.Config) *eurekaResolver

Example:

func main() {
    // ...
    config := fargo.Config{
    // ...
    }
    cli, err := client.NewClient()
    if err != nil {
        hlog.Fatal(err)
        return
    }
    r := eureka.NewEurekaResolverFromConfig(config)

    cli.Use(sd.Discovery(r))
    // ...
}

NewEurekaResolverFromConn

NewEurekaResolverFromConn uses eureka to create a new service discovery center, which needs to be passed directly to conn.

Function signature:

func NewEurekaResolverFromConn(conn fargo.EurekaConnection) *eurekaResolver

Example:

func main() {
    // ...
    conn := fargo.EurekaConnection{
    // ...
    }
    cli, err := client.NewClient()
    if err != nil {
        hlog.Fatal(err)
        return
    }
    r := eureka.NewEurekaResolverFromConn(conn)

    cli.Use(sd.Discovery(r))
    // ...
}

How to use

Server

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

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/seureka"
)

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))
    }
}

Configuration

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

Complete Example

For more, see example .


Last modified June 26, 2024 : doc: add construct use case (#1098) (83b7cf9)