main.go

package main

import (
	"context"
	"fmt"
	"log"
	"net/http"
	"os"
	"time"
)

func main() {
	s := &http.Server{
		Addr: ":9132",
	}

	http.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
		f := w.(http.Flusher)

		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
		defer cancel()

		for {
			select {
			case <-req.Context().Done():
				return
			case <-ctx.Done():
				return
			default:
				time.Sleep(1 * time.Second)
				fmt.Fprintln(w, time.Now().String())
				f.Flush()
			}
		}
	})

	http.HandleFunc("/anhero", func(w http.ResponseWriter, req *http.Request) {
		go func() {
			err := s.Shutdown(context.Background())
			if err != nil {
				panic(err)
			}
		}()
	})

	err := s.ListenAndServe()
	if err != nil {
		switch err {
		case http.ErrServerClosed:
			s.SetKeepAlivesEnabled(false)

			time.Sleep(30 * time.Second)

			log.Println("goodbye cruel world")
			os.Exit(0)
		default:
			panic(err)
		}
	}
}