app.go

package app

import (
	"context"
	"fmt"
	"github.com/gin-gonic/gin"
	"github.com/gin-gonic/gin/binding"
	"github.com/go-playground/validator/v10"
	"github.com/prometheus/client_golang/prometheus/promhttp"
	"github.com/spf13/pflag"
	ah "github.com/zhifeifu/fwds/internal/api/http"
	"github.com/zhifeifu/fwds/internal/job"
	"github.com/zhifeifu/fwds/internal/router"
	"github.com/zhifeifu/fwds/pkg/config"
	"github.com/zhifeifu/fwds/pkg/db"
	"github.com/zhifeifu/fwds/pkg/email"
	"github.com/zhifeifu/fwds/pkg/log"
	"github.com/zhifeifu/fwds/pkg/redis"
	"github.com/zhifeifu/fwds/pkg/trace"
	"github.com/zhifeifu/fwds/pkg/valid"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"
)

func Flag() string {
	var cfgFile = pflag.StringP("config", "c", "", "fwds config file path")
	pflag.Parse()
	return *cfgFile
}

func Run() {
	//获取启动时带的参数
	cfgFile := Flag()
	//初始化配置
	cfg, err := config.Init(cfgFile)
	if err != nil {
		panic(cfg)
	}
	//日志初始化
	log.Init(&cfg.Log)
	//数据库初始化
	db.Init(cfg.Mysql)
	//redis初始化
	redis.Init(&cfg.Redis)
	//链路跟踪初始化
	trace.Init(cfg)
	// Set gin mode.
	gin.SetMode(cfg.App.Mode)
	// 邮箱客户端 初始化
	email.Init(&cfg.Email)
	// 定时任务初始化
	job.Init()
	// http 服务
	HttpService(cfg)
}

func pprof(cfg *config.AppConfig) {
	go func() {
		fmt.Printf("Listening and serving PProf HTTP on %s\n", cfg.PprofPort)
		if err := http.ListenAndServe(cfg.PprofPort, http.DefaultServeMux); err != nil && err != http.ErrServerClosed {
			log.Fatalf("listen ListenAndServe for PProf, err: %s", err.Error())
		}
	}()
}

func HttpService(cfg *config.Config) {
	// Create the Gin engine.
	ge := gin.Default()
	//custom validator
	if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
		_ = v.RegisterValidation("phone", valid.Phone)
	}
	// HealthCheck 健康检查路由
	ge.GET("/health", ah.HealthCheck)
	// metrics router 可以在 prometheus 中进行监控
	ge.GET("/metrics", gin.WrapH(promhttp.Handler()))
	// API Routes.
	router.Load(ge)
	log.Infof("Start to listening the incoming requests on http address: %s", cfg.Http.Addr)
	srv := &http.Server{
		Addr:    cfg.Http.Addr,
		Handler: ge,
	}
	go func() {
		// service connections
		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("listen: %s", err.Error())
		}
	}()
	gracefulStop(srv)
}

// gracefulStop 优雅退出
// 等待中断信号以超时 5 秒正常关闭服务器
// 官方说明：https://github.com/gin-gonic/gin#graceful-restart-or-stop
func gracefulStop(srv *http.Server) {
	quit := make(chan os.Signal)
	// kill 命令发送信号 syscall.SIGTERM
	// kill -2 命令发送信号 syscall.SIGINT
	// kill -9 命令发送信号 syscall.SIGKILL
	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
	<-quit
	log.Info("Shutdown Server ...")
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()
	if err := srv.Shutdown(ctx); err != nil {
		log.Fatal("Server Shutdown:", err)
	}
	// 5 秒后捕获 ctx.Done() 信号
	select {
	case <-ctx.Done():
		log.Info("timeout of 5 seconds.")
	default:
	}
	log.Info("Server exiting")
}