webpack is a bundler for modules. The main purpose is to bundle javascript files for usage in a browser.
TL;DR
- bundles CommonJs and AMD modules. (even combined)
- can create a single bundle or multiple chunks loaded on demand, to reduce initial loading time.
- dependencies are resolved during compilation reducing the runtime size
- loaders can preprocess files while compiling, i. e. coffee-script to javascript
Check the documentation if you want to know more...
project:
npm install webpack --save-dev
global:
npm install webpack -g
Take a look at the examples
folder.
webpack has a rich plugin interface. Most of the features within webpack itself use this plugin interface. This makes webpack very flexible.
webpack uses async I/O and has multiple caching levels. This makes webpack fast and incredibly fast on incremental compilations.
webpack enables use of loaders to preprocess files. This allows you to bundle any static resource way beyond javascript. You can easily write your own loaders using node.js.
webpack supports AMD and CommonJS module styles. It performs clever static analysis on the AST of your code. It even has an evaluation engine to evaluate simple expressions. This allows you to support most existing libraries.
webpack allows you to split your codebase into multiple chunks. Chunks are loaded on demand. This reduces the initial loading time.
webpack can do many optimizations to reduce the output size. It also can make your chunks cache friendly by using hashes.
// webpack is a module bundler
// This means webpack takes modules with dependencies
// and emit static assets representing that modules.
// dependencies can be written in CommonJs
var commonjs = require("./commonjs");
// or in AMD
define(["amd-module", "../file"], function(amdModule, file) {
// while previous constructs are sync
// this is async
require(["big-module/big/file"], function(big) {
// for async dependencies webpack splits
// your application into multiple "chunks".
// This part of your application is
// loaded on demand (Code Splitting)
var stuff = require("../my/stuff");
// "../my/stuff" is also loaded on demand
// because it's in the callback function
// of the AMD require
});
});
require("coffee!./cup.coffee");
// "Loaders" can be used to preprocess files.
// They can be prefixed in the require call
// or configured in the configuration.
require("./cup");
// This does the same when you add ".coffee" to the extensions
// and configure the "coffee" loader for /\.coffee$/
function loadTemplate(name) {
return require("./templates/" + name + ".jade");
// many expression are supported in require calls
// a clever parser extract information and concludes
// that everything in "./templates" that matches
// /\.jade$/ should be included in the bundle, as it
// can be required.
}
// ... and you can combine everything
function loadTemplateAsync(name, callback) {
require(["bundle?lazy!./templates/" + name + ".jade"],
function(templateBundle) {
templateBundle(callback);
});
}
You can run the node tests with npm test
.
You can run the browser tests:
cd test/browsertests
node build
and open tests.html
in browser.
You are welcome to contribute by opening an issue or a pull request. It would be nice if you open sourced your own loaders or webmodules. :)
You are also welcome to correct any spelling mistakes or any language issues, because my english is not perfect...
If you want to discus something or just need help, here is a gitter.im room.
Copyright (c) 2012-2014 Tobias Koppers
MIT (https://www.opensource.org/licenses/mit-license.php)
This is a freetime project. My time investment fluctuates randomly. If you use webpack for a serious task you may want me to invest more time. Or if you make some good revenue you can give some money back. Keep in mind that this project may increase your income. It makes development and applications faster and reduce the required bandwidth.
I'm very thankful for every dollar. If you leave your username or email I may show my thanks by giving you extra support.