main.go

var port = flag.Uint("port", 8080, "port to listen")
var fd = flag.Uint("fd", 0, "fd to listen and serve")

func init() {
  flag.Parse()
}

func main() {
  sigchan := make(chan os.Signal)
  signal.Notify(sigchan, syscall.SIGTERM)
  signal.Notify(sigchan, syscall.SIGINT)

  var l net.Listener
  var err error

  if *fd == 0 {
    log.Println(fmt.Sprintf("listening on port %d", *port))
    l, err = net.ListenTCP("tcp", &net.TCPAddr{Port: int(*port)})
  } else {
    log.Println("listening on socket")
    l, err = net.FileListener(os.NewFile(uintptr(*fd), ""))
  }

  if err != nil {
    log.Fatal(err)
    panic(err)
  }

  go func() {
    log.Println(http.Serve(l, nil))
  }()

  <-sigchan
}