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Rafał Lorenz edited this page Jun 1, 2017 · 2 revisions
  1. HostSwitch


// We need an object that implements the http.Handler interface.
// Therefore we need a type for which we implement the ServeHTTP method.
// We just use a map here, in which we map host names (with port) to http.Handlers
type HostSwitch map[string]http.Handler

// Implement the ServerHTTP method on our new type
func (hs HostSwitch) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	// Check if a http.Handler is registered for the given host.
	// If yes, use it to handle the request.
	if handler := hs[r.Host]; handler != nil {
		handler.ServeHTTP(w, r)
	} else {
		// Handle host names for wich no handler is registered
		http.Error(w, "Forbidden", 403) // Or Redirect?

func main() {
	// Initialize a router as usual
	router := gorouter.New()
	router.GET("/", http.HandlerFunc(Index))
	router.GET("/hello/{name}", http.HandlerFunc(Hello))

	// Make a new HostSwitch and insert the router (our http handler)
	// for and port 12345
	hs := make(HostSwitch)
	hs[""] = router

	// Use the HostSwitch to listen and serve on port 12345
	log.Fatal(http.ListenAndServe(":12345", hs))
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