livereload package

import ""

package livereload handles Server-sent events and injection of the livereload script into upstream HTML pages.

To get started, create a Handler struct, serve it as you wish and call ForwardMessages to trigger reloads.

package main

import (


func main() {
	// Handler wiring
	livereloadHandler := &livereload.Handler{
		// Wire your own http.Handler here (eg http.FileServer)
		Upstream: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			// The Content-Type must contain text/html for the livereload script to be injected
			w.Header().Set("Content-Type", "text/html; charset=utf-8")
		LogRequest:      livereload.SingleLineRequestLogger(80, false),
		LogSlowResponse: livereload.SlowResponseLogger(time.Second),
	s := http.Server{
		Handler: livereloadHandler,
		Addr:    ":1234",
	go s.ListenAndServe()
	defer s.Close()

	http.Get("http://localhost:1234/") // a livereload script will be injected in HTML responses

	// Reload wiring (usually connected to os.Signal or os.Stdin)
	messages := make(chan string)
	go func() {
		messages <- "reload" // trigger a reload to all connected browsers

	livereloadHandler.ForwardMessages(messages, 5*time.Millisecond, time.Second)



200 GET /                                                                     0s



func SingleLineRequestLogger

SingleLineRequestLogger will print a colored line for each request, for instance:

200 GET /style.css                                                         300µs
Code Method RequestURI                                              ResponseTime

func SlowResponseLogger

SlowResponseLogger will print a colored line for each request when the headers weren't sent within the timeout, for instance:

slow response (>1s)  GET /devf/style.css
RedMessage           Method RequestURI

type FallbackFS

FallbackFS will try to Open a file from each of the underlying fs, until succesful.

func (FallbackFS) Open

type Handler

Handler is a wrapper to manage livereloading. Only the Upstream field is required. See SingleLineRequestLogger and SlowResponseLogger for the optional LogRequest and LogSlowResponse fields.

func (*Handler) ForwardMessages

ForwardMessages forwards the non-empty messages to the webpage, to trigger a reload. This method returns when the message channel is closed.

func (*Handler) ServeHTTP

ServeHTTP handles /.devf/* requests and inject the livereload script to html responses of the Upstream http.Handler.

Source Files

fallbackfs.go handler.go logger.go sse.go