livereload

What is livereload?

The livereload npm package allows developers to automatically refresh the browser whenever files are modified. This is particularly useful for web development, as it speeds up the development process by eliminating the need to manually refresh the browser to see changes.

What are livereload's main functionalities?

Automatic Browser Refresh

This feature sets up a LiveReload server that watches the specified directory (in this case, the 'public' directory). Whenever a file in this directory changes, the server will automatically refresh the browser.

const livereload = require('livereload');
const server = livereload.createServer();
server.watch(__dirname + '/public');

Custom File Extensions

This feature allows you to specify custom file extensions to watch. In this example, the server will only watch for changes in files with the extensions 'html', 'css', and 'js'.

const livereload = require('livereload');
const server = livereload.createServer({ exts: ['html', 'css', 'js'] });
server.watch(__dirname + '/public');

Excluding Files and Directories

This feature allows you to exclude certain files or directories from being watched. In this example, the server will ignore files with the '.map' extension and anything in the 'node_modules' directory.

const livereload = require('livereload');
const server = livereload.createServer({ exclusions: ['*.map', 'node_modules/**'] });
server.watch(__dirname + '/public');

Other packages similar to livereload

browser-sync

BrowserSync is a powerful tool for synchronizing file changes across multiple devices and browsers. It offers more features than livereload, such as synchronized scrolling, form replication, and a user interface for controlling the server. However, it is also more complex to set up and configure.

webpack-dev-server

Webpack Dev Server is a development server that provides live reloading and hot module replacement. It is tightly integrated with Webpack, making it a great choice for projects that already use Webpack for module bundling. It offers more advanced features like hot module replacement, which livereload does not.

gulp-livereload

Gulp-livereload is a plugin for Gulp that integrates livereload functionality into Gulp tasks. It is a good choice for projects that use Gulp as their task runner, providing a seamless way to add live reloading to the build process.

README

node-livereload

An implementation of the LiveReload server in Node.js. It's an alternative to the graphical http://livereload.com/ application, which monitors files for changes and reloads your web browser.

Usage

You can use this by using the official browser extension or by adding JavaScript code to your page.

Method 1: Use Browser Extension

Install the LiveReload browser plugins by visiting http://help.livereload.com/kb/general-use/browser-extensions.

Note: Only Google Chrome supports viewing file:/// URLS, and you have to specifically enable it. If you are using other browsers and want to use file:/// URLs, add the JS code to the page as shown in the next section.

Once you have the plugin installed, start livereload. Then, in the browser, click the LiveReload icon to connect the browser to the server.

Method 2: Add code to page

Add this code:

<script>
  document.write('<script src="http://' + (location.host || 'localhost').split(':')[0] +
  ':35729/livereload.js?snipver=1"></' + 'script>')
</script>

Note: If you are using a different port other than 35729 you will need to change the above script.

Running LiveReload

You can run LiveReload two ways: using the CLI application or by writing your own server using the API.

Method 1: Using the Command line Interface

To use livereload from the command line:

$ npm install -g livereload
$ livereload [path] [options]

To watch files in the current directory for changes and use the default extensions, run this command:

$ livereload

To watch files in another directory, specify its path:

$ livereload ~/website

The commandline options are

• -p or --port to specify the listening port
• -d or --debug to show debug messages when the browser reloads.
• -e or --exts to specify extentions that you want to observe. Example: -e 'jade,scss'. Removes the default extensions.
• -ee or --extraExts to include additional extentions that you want to observe. Example: -ee 'jade,scss'.
• -x or --exclusions to specify additional exclusion patterns. Example: -x html, images/.
• -u or --usepolling to poll for file system changes. Set this to true to successfully watch files over a network.
• -w or --wait to add a delay (in miliseconds) between when livereload detects a change to the filesystem and when it notifies the browser.
• -op or --originalpath to set a URL you use for development, e.g 'http:/domain.com', then LiveReload will proxy this url to local path.

For example, to use a wait time and turn on debugging so you can see messages in your terminal, execute livereload like this:

$ livereload -w 1000 -d

To turn on debugging and tell Livereload to only look at HTML files in the public directory, run it like this:

$ livereload public/ -e 'html'

The file path can be at any place in the arguments. For example, you can put it at the end if you wish:

$ livereload -e 'html' public/

Finally, you can tell LiveReload to refresh the browser when specific filenames change. This is useful when there are files that don't have extensions, or when you want to exclude all HTML files except for index.html throughout the project. Use the -f or --filesToReload option:

$ livereload -f 'index.html' public/

All changes to index.html in any subdirectory will cause LiveReload to send the reload message.

Option 2: From within your own project

To use the api within a project:

$ npm install livereload --save

Then, create a server and fire it up.

var livereload = require('livereload');
var server = livereload.createServer();
server.watch(__dirname + "/public");

You can also use this with a Connect server. Here's an example of a simple server using connect and a few other modules just to give you an idea:

var connect  = require('connect');
var compiler = require('connect-compiler');
var static = require('serve-static');

var server = connect();

server.use(
  compiler({
      enabled : [ 'coffee', 'uglify' ],
      src     : 'src',
      dest    : 'public'
  })
);

server.use(  static(__dirname + '/public'));

server.listen(3000);

var livereload = require('livereload');
var lrserver = livereload.createServer();
lrserver.watch(__dirname + "/public");

You can then start up the server which will listen on port 3000.

Server API

The createServer() method accepts two arguments.

The first are some configuration options, passed as a JavaScript object:

• https is an optional object of options to be passed to https.createServer (if not provided, http.createServer is used instead)
• port is the listening port. It defaults to 35729 which is what the LiveReload extensions use currently.
• exts is an array of extensions you want to observe. This overrides the default extensions of [html, css, js, png, gif, jpg, php, php5, py, rb, erb, coffee].
• extraExts is an array of extensions you want to observe. The default extensions are [html, css, js, png, gif, jpg, php, php5, py, rb, erb, coffee].
• applyCSSLive tells LiveReload to reload CSS files in the background instead of refreshing the page. The default for this is true.
• applyImgLive tells LiveReload to reload image files in the background instead of refreshing the page. The default for this is true. Namely for these extensions: jpg, jpeg, png, gif
• exclusions lets you specify files to ignore. By default, this includes .git/, .svn/, and .hg/
• originalPath Set URL you use for development, e.g 'http:/domain.com', then LiveReload will proxy this url to local path.
• overrideURL lets you specify a different host for CSS files. This lets you edit local CSS files but view a live site. See http://feedback.livereload.com/knowledgebase/articles/86220-preview-css-changes-against-a-live-site-then-uplo for details.
• usePolling Poll for file system changes. Set this to true to successfully watch files over a network.
• delay add a delay (in miliseconds) between when livereload detects a change to the filesystem and when it notifies the browser. Useful if the browser is reloading/refreshing before a file has been compiled, for example, by browserify.
• noListen Pass as true to indicate that the websocket server should not be started automatically. (useful if you want to start it yourself later)

The second argument is an optional callback that will be sent to the LiveReload server and called for the listening event. (ie: when the server is ready to start accepting connections)

Watching multiple paths:

Passing an array of paths or glob patterns will allow you to watch multiple directories. All directories have the same configuration options.

server.watch([__dirname + "/js", __dirname + "/css"]);

Command line:

$ livereload "path1, path2, path3"

Using the originalPath option

You can map local CSS files to a remote URL. If your HTML file specifies live CSS files at example.com like this:

<!-- html -->
<head>
  <link rel="stylesheet" href="http://domain.com/css/style.css">
</head>

Then you can tell livereload to substitute a local CSS file instead:

// server.js
var server = livereload.createServer({
    originalPath: "http://domain.com"
});
server.watch('/User/Workspace/test');

Then run the server:

$ node server.js

When /User/Workspace/test/css/style.css is modified, the stylesheet will be reloaded on the page.

Troubleshooting

The browser extension doesn't connect.

If you're using file:/// urls, make sure the browser extension is configured to access local files. Alternatively, embed the livereload.js script on your page as shown in this README.

When I change the HTML page I'm working on, the browser refreshes and tells me the file isn't found.

Your editor is most likely using a swapfile, and when you save, there's a split second where the existing file is deleted from the file system before the swap file is saved in its place. This happens with Vim. You can disable swapfiles in your editor, or you can add a slight delay to Livereload using the -w option on the command line.

Developing livereload

This library is implemented in CoffeeScript 1.x. It may eventually be converted to JavaScript, but because there are many projects that depend on this library, the conversion isn't a priority.

To build the distributable versions, run npm run build.

Run npm test to run the test suite.

Contributing

Contributions welcome, but remember that this library is meant to be small and serve its intended purpose only. Before submitting a pull request, open a new issue to discuss your feature or bug. Please check all open and closed issues.

When submitting code, please keep commits small, and do not modify the README file. Commit both the Coffee and JS files.

Changelog

0.9.2

• Server: Added filesToReload option to specify a list of filenames that should trigger the reload, rather than relying on extensions alone.
• CLI: You can use the -f or --filesToReload option with the command line tool to specifiy filenames that should trigger a reload.
• CLI: The file path is no longer fixed to a specific position in the arguments list
• CLI: You no longer need to specify the file path when using additional arguments
• CLI: You can use the -op or --originalpath option with the command line tool instead of writing your own server.
• CLI: The help screen displays more accurate option descriptions.
• Tests: Added more specific tests to ensure that refresh is called in various scenarios.
• Other: Removed Cakefile as Cake is no longer needed. Use npm run tests and npm run build instead.
• Dependencies: Updated chokidar dependency to 3.5.1
• Dependencies: Updated livereload-js dependency to 3.3.1
• Dependencies: Updated ws dependency to 7.4.3

0.9.1

• Fix issue with livereload.js not resolving properly on some projects (caseywebdev)
• Update license to newer style to suppress "no license" messages.
• Update test scripts to handle compilers properly, suppressing the deprecation notice
• Deprecating the cake tasks for building the project.

0.9.0

• Serve Livereload client library from an NPM dependency instead of copying the code into the project - smhg
• Update Chokidar to 3.3.0 which improves performance and reduces CPU load.

0.8.2

• Fix regression in 0.8.1 where broadcasting failed due to incompatibility between arrays and sets
• Add debug message when broadcasting to each socket
• Add debug message for the input message from clients

0.8.1

• Update ws dependency to v6.2.1 to close security vulnerability

0.8.0

• Update bundled Livereload.js file to v3.0.0
• Update deps to close security vulnerabilities

0.7.0

• Updates bundled Livereload.js file to v2.3.0 to fix console error.
• BREAKING CHANGE: The exts and e options now replace the default extensions.
• Adds the extraExts and ee options to preserve the old behavior of adding extensions to watch.
• You can now use server.on 'error' in your code to catch the "port in use" message gracefully. The CLI now handles this nicely as well.

0.6.3

• Updated to use Chokidar 1.7, which hopefully fixes some memory issues.
• BUGFIX: Check to see if a watcher object is actually defined before attempting to close.
• Added deprecation warning for exts option. In the next version, extensions you specify on the command line will OVERRIDE the default extensions. We'll add a new option for adding your exts to the defaults.
• Modified CLI so it trims spaces from the extensions in the array, just in case you put spaces between the commas.

0.6.2

• CLI now properly splits extension list. Previous versions appended a blank entry to the list of extensions.
• CLI now requires extensions to be comma separated instead of space separated.
• Added extra debugging info (protocol version, watched directory, extensions, and exclusions).
• Cleaned up some inconsistencies in the code.

0.6.1

• Fix default exclusions regex

0.6.0

• Implements LiveReload protocol v7 so browser plugins work again.
• Removes support for protocol v6
• Introduces noListen option
• Introduces optional callback which will be invoked when the LiveReload server is listening

0.5.0

• Updated ws library
• Fix issues with exclusions
• Allow watching multiple paths from CLI
• Added delay option

0.4.1

• Remove some bad JS code

0.4.0

• Rewritten using Chokidar library and ws library
• Added usePolling option
• Added support for specifying additional extensions from the CLI

Older version history not kept.

License

Copyright (c) 2010-2021 Brian P. Hogan and Joshua Peek

Released under the MIT license. See LICENSE for details.