consul

Service Registration and Discovery consul Extensions provided by Hertz.

Install

go get github.com/hertz-contrib/registry/consul

Service Registry

Option

Consul extension provides option configuration in the service registry section.

WithCheck

Consul extension provides WithCheck to help users configure the AgentServiceCheck option in Consul. defaultCheck() is called by default. If not use, set check.Timeout to 5 seconds, check.Internal to 5 seconds, and check.DeregisterCriticalServiceAfter to 1 minute.

Function signature:

func WithCheck(check *api.AgentServiceCheck) Option

Example:

func main() {
    // ...
    consulClient, err := consulapi.NewClient(config)
    // ...
    check := &consulapi.AgentServiceCheck{
        // ...
    }
    r := consul.NewConsulRegister(consulClient, consul.WithCheck(check))
    h := server.Default(
        server.WithHostPorts(addr),
        server.WithRegistry(r, &registry.Info{
            ServiceName: "hertz.test.demo",
            Addr:        utils.NewNetAddr("tcp", addr),
            Weight:      10,
            Tags:        nil,
        }),
    )
    // ...
}

NewConsulRegister

NewConsulRegister uses consul to create a new service registry, which needs to be passed in a client, which is created with NewClient. The service registry configuration can be customized.

Function signature:

func NewConsulRegister(consulClient *api.Client, opts ...Option) registry.Registry

Example:

func main() {
    // ...
    consulClient, err := consulapi.NewClient(config)
    // ...
    r := consul.NewConsulRegister(consulClient)
    h := server.Default(
        server.WithHostPorts(addr),
        server.WithRegistry(r, &registry.Info{
            ServiceName: "hertz.test.demo",
            Addr:        utils.NewNetAddr("tcp", addr),
            Weight:      10,
            Tags:        nil,
        }),
    )
    // ...
}

Service Discovery

NewConsulResolver

NewConsulResolver uses consul to create a new service discovery center, you need to pass in the client. The client is created using NewClient. The service discovery center configuration can be customized.

Function signature:

func NewConsulResolver(consulClient *api.Client) discovery.Resolver

Example:

func main() {
    // ...
    consulClient, err := consulapi.NewClient(consulConfig)
    if err != nil {
        log.Fatal(err)
        return
    }
    r := consul.NewConsulResolver(consulClient)

    cli, err := client.NewClient()
    if err != nil {
        panic(err)
    }
    cli.Use(sd.Discovery(r))
}

How to use

Server

import (
    "context"
    "log"

    "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"
    consulapi "github.com/hashicorp/consul/api"
    "github.com/hertz-contrib/registry/consul"
)


func main() {
    // build a consul client
    config := consulapi.DefaultConfig()
    config.Address = "127.0.0.1:8500"
    consulClient, err := consulapi.NewClient(config)
    if err != nil {
        log.Fatal(err)
        return
    }
    // build a consul register with the consul client
    r := consul.NewConsulRegister(consulClient)

    // run Hertz with the consul register
    addr := "127.0.0.1:8888"
    h := server.Default(
        server.WithHostPorts(addr),
        server.WithRegistry(r, &registry.Info{
            ServiceName: "hertz.test.demo",
            Addr:        utils.NewNetAddr("tcp", addr),
            Weight:      10,
            Tags:        nil,
        }),
    )
    h.GET("/ping", func(ctx context.Context, c *app.RequestContext) {
        c.JSON(consts.StatusOK, utils.H{"ping": "pong1"})
    })
    h.Spin()
}

Client

import (
    "log"

    "github.com/cloudwego/hertz/pkg/app/client"
    "github.com/cloudwego/hertz/pkg/app/middlewares/client/sd"
    consulapi "github.com/hashicorp/consul/api"
    "github.com/hertz-contrib/registry/consul"
)

func main() {
    // build a consul client
    consulConfig := consulapi.DefaultConfig()
    consulConfig.Address = "127.0.0.1:8500"
    consulClient, err := consulapi.NewClient(consulConfig)
    if err != nil {
        log.Fatal(err)
        return
    }
    // build a consul resolver with the consul client
    r := consul.NewConsulResolver(consulClient)

    // build a hertz client with the consul resolver
    cli, err := client.NewClient()
    if err != nil {
        panic(err)
    }
    cli.Use(sd.Discovery(r))
}

Configuration

The configuration of Consul client and server can be customized, refer to the configuration of consul.

Complete Example

For more, see example .