webpack/lib/dependencies/LoaderPlugin.js

Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support loaders to preprocess files, i.e. json, jade, coffee, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/
var LoaderDependency = require("./LoaderDependency");

function LoaderPlugin() {
}
module.exports = LoaderPlugin;

LoaderPlugin.prototype.apply = function(compiler) {
	compiler.plugin("compilation", function(compilation, params) {
		var normalModuleFactory = params.normalModuleFactory;

		compilation.dependencyFactories.set(LoaderDependency, normalModuleFactory);
	});
	compiler.plugin("compilation", function(compilation) {
		var cache = {};
		compilation.plugin("normal-module-loader", function(loaderContext, module) {
			loaderContext.loadModule = function loadModule(request, callback) {
				var dep = new LoaderDependency(request);
				compilation.addModuleDependencies(module, [[dep]], true, "lm", false, function(err) {
					if(err) return callback(err);
					
					module = dep.module;
					if(!module) return callback(new Error("Cannot load the module"));
					if(module.building) module.building.push(next);
					else next();

					function next(err) {
						if(err) return callback(err);

						if(dep.module.error) return callback(dep.module.error);
						if(!dep.module._source) throw new Error("The module created for a LoaderDependency must have a property _source");
						var map = dep.module._source.map();
						var source = dep.module._source.source();
						if(dep.module.fileDependencies) {
							dep.module.fileDependencies.forEach(function(dep) {
								loaderContext.addDependency(dep);
							});
						}
						if(dep.module.contextDependencies) {
							dep.module.contextDependencies.forEach(function(dep) {
								loaderContext.addContextDependency(dep);
							});
						}
						return callback(null, source, map, dep.module);
					}
				});
			};
		});
	});
};