package consul

import (
    "fmt"
    "io/ioutil"

    "gitee.com/natas-public/utils/net"
    "gitee.com/natas-public/utils/str"

    consulApi "github.com/hashicorp/consul/api"

    yaml "gopkg.in/yaml.v2"
)

type Config struct {
    Consul struct {
        Server   string   `yaml:"server"`
        Port     string   `yaml:"port"`
        ID       string   `yaml:"id"`
        Name     string   `yaml:"name"`
        Tags     []string `yaml:"tags,flow"`
        Timeout  int      `yaml:"timeout"`
        Interval int      `yaml:"interval"`
        Dcsafter int      `yaml:"dcsafter"`

        Client struct {
            IP     string `yaml:"ip"`
            Port   int    `yaml:"port"`
            Health string `yaml:"health"`
        } `yaml:"client"`
    } `yaml:"consul"`
}

var (
    client *consulApi.Client
)

func Register() error {

    var (
        err     error
        ymlConf []byte
    )

    if ymlConf, err = ioutil.ReadFile("./conf/consul.yml"); nil != err {
        return err
    }

    config := new(Config)
    config.Consul.ID = str.GetRandomString(8)
    config.Consul.Name = str.GetRandomString(16)
    config.Consul.Client.IP = net.GetLocalIP()
    config.Consul.Timeout = 5
    config.Consul.Interval = 5
    config.Consul.Dcsafter = 30

    if err = yaml.Unmarshal(ymlConf, config); nil != err {
        return err
    }

    consulConfig := consulApi.DefaultConfig()
    consulConfig.Address = fmt.Sprintf("%s:%s", config.Consul.Server, config.Consul.Port)
    if client, err = consulApi.NewClient(consulConfig); nil != err {
        return err
    }

    // 创建注册到consul的服务到
    registration := new(consulApi.AgentServiceRegistration)
    registration.ID = config.Consul.ID
    registration.Name = config.Consul.Name
    registration.Port = config.Consul.Client.Port
    registration.Tags = config.Consul.Tags
    registration.Address = config.Consul.Client.IP

    // 增加consul健康检查回调函数
    check := new(consulApi.AgentServiceCheck)
    check.HTTP = fmt.Sprintf("http://%s:%d%s", registration.Address, registration.Port, config.Consul.Client.Health)
    check.Timeout = fmt.Sprintf("%ds", config.Consul.Timeout)
    check.Interval = fmt.Sprintf("%ds", config.Consul.Interval)
    check.DeregisterCriticalServiceAfter = fmt.Sprintf("%ds", config.Consul.Dcsafter) // 故障检查失败30s后 consul自动将注册服务删除
    registration.Check = check

    // 注册服务到consul
    if err = client.Agent().ServiceRegister(registration); nil != err {
        return err
    }

    return nil
}