package main

import (
	"flag"
	"fmt"
	"github.com/google/uuid"
	"github.com/hashicorp/consul/api"
	"log"
	"net/http"
	"time"
)

const ConsulServerAddress = "192.168.177.131:8500"

func main() {
	// 处理命令行参数
	addr := flag.String("addr", "127.0.0.1", "The Address for listen. Default is 127.0.0.1")
	port := flag.Int("port", 8080, "The Port for listen. Default is 8080.")
	flag.Parse()

	// 拼凑完整地址
	address := fmt.Sprintf("%s:%d", *addr, *port)

	// 定义业务逻辑服务，假设为产品服务
	service := http.NewServeMux()
	service.HandleFunc("/info", func(writer http.ResponseWriter, request *http.Request) {
		_, err := fmt.Fprintf(writer, "Product Service on %s. Now is %s", address, time.Now().String())
		if err != nil {
			log.Fatalln(err)
		}
	})
	// 增加 /health 路由处理器
	service.HandleFunc("/health", func(writer http.ResponseWriter, request *http.Request) {
		log.Println("Health Check.")
		_, err := fmt.Fprintf(writer, "Product Service Health Check.")
		if err != nil {
			log.Fatalln(err)
		}
	})

	// 定义注册中心的服务
	serviceReg := new(api.AgentServiceRegistration)
	serviceReg.Name = "Product"
	serviceReg.ID = "productService-" + uuid.NewString()
	serviceReg.Address = *addr
	serviceReg.Port = *port
	serviceReg.Tags = []string{"test"}
	// 定义服务的健康检查
	serviceReg.Checks = api.AgentServiceChecks{
		&api.AgentServiceCheck{
			CheckID:                        serviceReg.ID + "-check",
			Name:                           serviceReg.ID + "-check",
			Interval:                       "5s",
			Timeout:                        "1s",
			HTTP:                           fmt.Sprintf("http://%s/health", address),
			Method:                         "GET",
			Notes:                          "",
			SuccessBeforePassing:           0,
			FailuresBeforeWarning:          0,
			FailuresBeforeCritical:         0,
			DeregisterCriticalServiceAfter: "",
		},
	}

	// 注册服务
	// 连接 consul ，作为客户端连接 consul
	consulApiConfig := api.DefaultConfig()
	consulApiConfig.Address = ConsulServerAddress
	consulClient, err := api.NewClient(consulApiConfig)
	if err != nil {
		log.Fatalln(err)
	}
	// 发出 put 注册请求
	if err := consulClient.Agent().ServiceRegister(serviceReg); err != nil {
		log.Fatalln(err)
	}
	log.Println("Service Product has be registered.")

	// 启动监听
	fmt.Printf("Product service is listening on %s.\n", address)
	log.Fatalln(http.ListenAndServe(address, service))
}