shutdown-hooks.go

package main

import (
	"context"
	"fmt"
	log "github.com/sirupsen/logrus"
	"os"
	"os/signal"
	"sync"
	"syscall"
	"time"
)

func main() {
	log.Info("starting")
	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()

	var wg sync.WaitGroup
	c := make(chan string)

	go func() {
		wg.Add(1)
		defer wg.Done()
		done := false
		for !done {
			select {
			case <-ctx.Done():
				log.Infof("exiting for loop")
				done = true
				break
			case m := <-c:
				log.Infof("msg: %s", m)
			}
		}

		log.Infof("gracefully shutting down...")
		time.Sleep(1 * time.Second)
		log.Infof("gracefully shutdown complete")
	}()

	go func() {
		for {
			time.Sleep(1 * time.Second)
			c <- fmt.Sprintf("The date time is: %s", time.Now().Format(time.RFC850))
		}
	}()

	<-ctx.Done()
	log.Infof("Recieved shutdown signal, waiting for sync groups")
	wg.Wait()
}