Go API server shutdown with graceful timeout

signal.go

// Setup signal capture
signalShutdown := make(chan os.Signal, 1)
signal.Notify(signalShutdown, os.Interrupt, os.Kill, syscall.SIGTERM)
ctxCancel, cancel := context.WithCancel(context.Background())
wg := sync.WaitGroup{}

// Init API server
apiSrv := apiserver.New(ctxCancel, &wg)

// Start internal webserver
wg.Add(1)

// HTTP ListenAndServe
go apiSrv.Start()

// Will block until a signal is received to shut down the API
// When the shutdown signal is received, it executes a cancel context and forcefully stop the services if needed.
<-signalShutdown
fmt.Printf("\nWaiting for services to stop")

// Signal goroutines to cancel
cancel()

// Waiting for graceful stop
normalShutdown := make(chan struct{})
ticker := time.NewTicker(time.Second)
t := time.Now()
timeoutDuration := 10 * time.Second

go func() {
	wg.Wait()
	close(normalShutdown)
}()

loop:
for {
	select {
	case <-normalShutdown:
		break loop
	case <-ticker.C:
		fmt.Printf(".")

		if time.Since(t) >= timeoutDuration {
			fmt.Printf("\nTimed out, force killing services.")
			break loop
		}
	}
}

ticker.Stop()
fmt.Printf("\nAPI stopped.")