Implementing a graceful shutdown of http that is docker compatible

main.go

package main

import (
	"fmt"
	"io"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/braintree/manners"
)

func main() {

	shutdown := make(chan int)

	//create a notification channel to shutdown
	sigChan := make(chan os.Signal, 1)

	//start the http server
	http.HandleFunc("/", hello)
	server := manners.NewWithServer(&http.Server{Addr: ":80", Handler: nil})
	go func() {
		server.ListenAndServe()
		shutdown <- 1
	}()

	//register for interupt (Ctrl+C) and SIGTERM (docker)
	signal.Notify(sigChan, os.Interrupt, syscall.SIGTERM)
	go func() {
		<-sigChan
		fmt.Println("Shutting down...")
		server.Close()
	}()

	<-shutdown
}

func hello(w http.ResponseWriter, r *http.Request) {
	//pretend to do some work
	time.Sleep(3000 * time.Millisecond)
	io.WriteString(w, "Hello world!")
}