main.go

package main

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

func main() {
	block := make(chan os.Signal, 2)
	signal.Notify(block, os.Interrupt)
	server1 := newHTTPServer("server_1", ":9200")
	server2 := newHTTPServer("server_2", ":9201")

	go run(&server1)
	go run(&server2)

	<-block
	server1.Shutdown(context.Background())

	<-block
	server2.Shutdown(context.Background())
	close(block)

	return
}

func newHTTPServer(name string, addr string) http.Server {
	mux := http.NewServeMux()
	mux.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte(fmt.Sprintf("hello, server %v", name)))
	}))
	return http.Server{
		Addr:    addr,
		Handler: mux,
	}
}

func run(s *http.Server) {
	log.Printf("starting server listening on %v\n", s.Addr)
	if err := s.ListenAndServe(); err != nil {
		log.Print(err)
	}
}