webpack/lib/webworker/WebWorkerMainTemplatePlugin.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, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/
"use strict";

const Template = require("../Template");

class WebWorkerMainTemplatePlugin {
	apply(mainTemplate) {
		const needChunkOnDemandLoadingCode = chunk => {
			for (const chunkGroup of chunk.groupsIterable) {
				if (chunkGroup.getNumberOfChildren() > 0) return true;
			}
			return false;
		};
		mainTemplate.hooks.localVars.tap(
			"WebWorkerMainTemplatePlugin",
			(source, chunk) => {
				if (needChunkOnDemandLoadingCode(chunk)) {
					return Template.asString([
						source,
						"",
						"// object to store loaded chunks",
						'// "1" means "already loaded"',
						"var installedChunks = {",
						Template.indent(
							chunk.ids.map(id => `${JSON.stringify(id)}: 1`).join(",\n")
						),
						"};"
					]);
				}
				return source;
			}
		);
		mainTemplate.hooks.requireEnsure.tap(
			"WebWorkerMainTemplatePlugin",
			(_, chunk, hash) => {
				const chunkFilename = mainTemplate.outputOptions.chunkFilename;
				const chunkMaps = chunk.getChunkMaps();
				return Template.asString([
					"promises.push(Promise.resolve().then(function() {",
					Template.indent([
						'// "1" is the signal for "already loaded"',
						"if(!installedChunks[chunkId]) {",
						Template.indent([
							"importScripts(" +
								"__webpack_require__.p + " +
								mainTemplate.getAssetPath(JSON.stringify(chunkFilename), {
									hash: `" + ${mainTemplate.renderCurrentHashCode(hash)} + "`,
									hashWithLength: length =>
										`" + ${mainTemplate.renderCurrentHashCode(
											hash,
											length
										)} + "`,
									chunk: {
										id: '" + chunkId + "',
										hash: `" + ${JSON.stringify(chunkMaps.hash)}[chunkId] + "`,
										hashWithLength(length) {
											const shortChunkHashMap = Object.create(null);
											for (const chunkId of Object.keys(chunkMaps.hash)) {
												if (typeof chunkMaps.hash[chunkId] === "string") {
													shortChunkHashMap[chunkId] = chunkMaps.hash[
														chunkId
													].substr(0, length);
												}
											}
											return `" + ${JSON.stringify(
												shortChunkHashMap
											)}[chunkId] + "`;
										},
										contentHash: {
											javascript: `" + ${JSON.stringify(
												chunkMaps.contentHash.javascript
											)}[chunkId] + "`
										},
										contentHashWithLength: {
											javascript: length => {
												const shortContentHashMap = {};
												const contentHash = chunkMaps.contentHash.javascript;
												for (const chunkId of Object.keys(contentHash)) {
													if (typeof contentHash[chunkId] === "string") {
														shortContentHashMap[chunkId] = contentHash[
															chunkId
														].substr(0, length);
													}
												}
												return `" + ${JSON.stringify(
													shortContentHashMap
												)}[chunkId] + "`;
											}
										},
										name: `" + (${JSON.stringify(
											chunkMaps.name
										)}[chunkId]||chunkId) + "`
									},
									contentHashType: "javascript"
								}) +
								");"
						]),
						"}"
					]),
					"}));"
				]);
			}
		);
		mainTemplate.hooks.bootstrap.tap(
			"WebWorkerMainTemplatePlugin",
			(source, chunk, hash) => {
				if (needChunkOnDemandLoadingCode(chunk)) {
					const chunkCallbackName =
						mainTemplate.outputOptions.chunkCallbackName;
					const globalObject = mainTemplate.outputOptions.globalObject;
					return Template.asString([
						source,
						`${globalObject}[${JSON.stringify(
							chunkCallbackName
						)}] = function webpackChunkCallback(chunkIds, moreModules) {`,
						Template.indent([
							"for(var moduleId in moreModules) {",
							Template.indent(
								mainTemplate.renderAddModule(
									hash,
									chunk,
									"moduleId",
									"moreModules[moduleId]"
								)
							),
							"}",
							"while(chunkIds.length)",
							Template.indent("installedChunks[chunkIds.pop()] = 1;")
						]),
						"};"
					]);
				}
				return source;
			}
		);
		mainTemplate.hooks.hotBootstrap.tap(
			"WebWorkerMainTemplatePlugin",
			(source, chunk, hash) => {
				const hotUpdateChunkFilename =
					mainTemplate.outputOptions.hotUpdateChunkFilename;
				const hotUpdateMainFilename =
					mainTemplate.outputOptions.hotUpdateMainFilename;
				const hotUpdateFunction = mainTemplate.outputOptions.hotUpdateFunction;
				const globalObject = mainTemplate.outputOptions.globalObject;
				const currentHotUpdateChunkFilename = mainTemplate.getAssetPath(
					JSON.stringify(hotUpdateChunkFilename),
					{
						hash: `" + ${mainTemplate.renderCurrentHashCode(hash)} + "`,
						hashWithLength: length =>
							`" + ${mainTemplate.renderCurrentHashCode(hash, length)} + "`,
						chunk: {
							id: '" + chunkId + "'
						}
					}
				);
				const currentHotUpdateMainFilename = mainTemplate.getAssetPath(
					JSON.stringify(hotUpdateMainFilename),
					{
						hash: `" + ${mainTemplate.renderCurrentHashCode(hash)} + "`,
						hashWithLength: length =>
							`" + ${mainTemplate.renderCurrentHashCode(hash, length)} + "`
					}
				);

				return (
					source +
					"\n" +
					`var parentHotUpdateCallback = ${globalObject}[${JSON.stringify(
						hotUpdateFunction
					)}];\n` +
					`${globalObject}[${JSON.stringify(hotUpdateFunction)}] = ` +
					Template.getFunctionContent(
						require("./WebWorkerMainTemplate.runtime")
					)
						.replace(/\/\/\$semicolon/g, ";")
						.replace(/\$require\$/g, mainTemplate.requireFn)
						.replace(/\$hotMainFilename\$/g, currentHotUpdateMainFilename)
						.replace(/\$hotChunkFilename\$/g, currentHotUpdateChunkFilename)
						.replace(/\$hash\$/g, JSON.stringify(hash))
				);
			}
		);
		mainTemplate.hooks.hash.tap("WebWorkerMainTemplatePlugin", hash => {
			hash.update("webworker");
			hash.update("4");
		});
	}
}
module.exports = WebWorkerMainTemplatePlugin;