webpack/lib/DynamicEntryPlugin.js

Packs ECMAScript/CommonJs/AMD modules for the browser. Allows you to split your codebase into multiple bundles, which can be loaded on demand. Supports loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Naoyuki Kanezawa @nkzawa
*/

"use strict";

const EntryOptionPlugin = require("./EntryOptionPlugin");
const EntryPlugin = require("./EntryPlugin");
const EntryDependency = require("./dependencies/EntryDependency");

/**
 * @import {
 * 	EntryDescriptionNormalized,
 * 	EntryStatic,
 * 	EntryStaticNormalized
 * } from "../declarations/WebpackOptions"
 */
/** @import Compiler from "./Compiler" */

const PLUGIN_NAME = "DynamicEntryPlugin";

/** @typedef {() => EntryStatic | Promise<EntryStatic>} RawEntryDynamic */
/** @typedef {() => Promise<EntryStaticNormalized>} EntryDynamic */

class DynamicEntryPlugin {
	/**
	 * Creates an instance of DynamicEntryPlugin.
	 * @param {string} context the context path
	 * @param {EntryDynamic} entry the entry value
	 */
	constructor(context, entry) {
		/** @type {string} */
		this.context = context;
		/** @type {EntryDynamic} */
		this.entry = entry;
	}

	/**
	 * Applies the plugin by registering its hooks on the compiler.
	 * @param {Compiler} compiler the compiler instance
	 * @returns {void}
	 */
	apply(compiler) {
		compiler.hooks.compilation.tap(
			PLUGIN_NAME,
			(compilation, { normalModuleFactory }) => {
				compilation.dependencyFactories.set(
					EntryDependency,
					normalModuleFactory
				);
			}
		);

		compiler.hooks.make.tapPromise(PLUGIN_NAME, (compilation) =>
			Promise.resolve(this.entry())
				.then((entry) => {
					/** @type {Promise<void>[]} */
					const promises = [];
					for (const name of Object.keys(entry)) {
						const desc = entry[name];
						const options = EntryOptionPlugin.entryDescriptionToOptions(
							compiler,
							name,
							desc
						);
						for (const entry of /** @type {NonNullable<EntryDescriptionNormalized["import"]>} */ (
							desc.import
						)) {
							promises.push(
								new Promise(
									/**
									 * Handles the callback logic for this hook.
									 * @param {(value?: undefined) => void} resolve resolve
									 * @param {(reason?: Error) => void} reject reject
									 */
									(resolve, reject) => {
										compilation.addEntry(
											this.context,
											EntryPlugin.createDependency(entry, options),
											options,
											(err) => {
												if (err) return reject(err);
												resolve();
											}
										);
									}
								)
							);
						}
					}
					return Promise.all(promises);
				})
				.then(() => {})
		);
	}
}

module.exports = DynamicEntryPlugin;