webpack/lib/web/JsonpChunkLoadingPlugin.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 Tobias Koppers @sokra
*/

"use strict";

const RuntimeGlobals = require("../RuntimeGlobals");
const lazyModule = require("../util/lazyModule");

/** @import Chunk from "../Chunk" */
/** @import Compiler from "../Compiler" */
/** @import { RuntimeRequirements } from "../Module" */

// only a chunk that loads other chunks at runtime emits this
const getJsonpChunkLoadingRuntimeModule = lazyModule(() =>
	require("./JsonpChunkLoadingRuntimeModule")
);

const PLUGIN_NAME = "JsonpChunkLoadingPlugin";

/**
 * Enables browser-side JavaScript chunk loading through the JSONP runtime and
 * adds the supporting runtime requirements for matching chunks.
 */
class JsonpChunkLoadingPlugin {
	/**
	 * Registers compilation hooks that attach the JSONP chunk-loading runtime
	 * module and its dependent runtime globals to chunks using `chunkLoading:
	 * "jsonp"`.
	 * @param {Compiler} compiler the compiler instance
	 * @returns {void}
	 */
	apply(compiler) {
		compiler.hooks.thisCompilation.tap(PLUGIN_NAME, (compilation) => {
			const globalChunkLoading = compilation.outputOptions.chunkLoading;
			/**
			 * Determines whether the chunk resolves JavaScript chunks through the
			 * JSONP loading backend.
			 * @param {Chunk} chunk chunk
			 * @returns {boolean} true, if wasm loading is enabled for the chunk
			 */
			const isEnabledForChunk = (chunk) => {
				const options = chunk.getEntryOptions();
				const chunkLoading =
					options && options.chunkLoading !== undefined
						? options.chunkLoading
						: globalChunkLoading;
				return chunkLoading === "jsonp";
			};
			/** @type {WeakSet<Chunk>} */
			const onceForChunkSet = new WeakSet();
			/**
			 * Adds the JSONP runtime module to a chunk once, along with the core
			 * runtime globals it relies on.
			 * @param {Chunk} chunk chunk
			 * @param {RuntimeRequirements} set runtime requirements
			 */
			const handler = (chunk, set) => {
				if (onceForChunkSet.has(chunk)) return;
				onceForChunkSet.add(chunk);
				if (!isEnabledForChunk(chunk)) return;
				compilation.addLazyRuntimeModule(
					chunk,
					getJsonpChunkLoadingRuntimeModule,
					(Ctor) => new Ctor(set)
				);
			};
			/**
			 * Installing a chunk, on load or on a hot update, is the only part that writes
			 * the module factories and looks a chunk id up; a base uri or `onChunksLoaded`
			 * comes without either. Kept off `handler`, which runs once per chunk and so
			 * cannot see which of the requirements below the chunk ends up with.
			 * @param {Chunk} chunk chunk to check
			 * @param {RuntimeRequirements} set runtime requirements
			 */
			const installHandler = (chunk, set) => {
				if (!isEnabledForChunk(chunk)) return;
				set.add(RuntimeGlobals.moduleFactoriesAddOnly);
				set.add(RuntimeGlobals.hasOwnProperty);
			};
			for (const requirement of [
				RuntimeGlobals.ensureChunkHandlers,
				RuntimeGlobals.hmrDownloadUpdateHandlers,
				RuntimeGlobals.hmrDownloadManifest,
				RuntimeGlobals.baseURI,
				RuntimeGlobals.onChunksLoaded
			]) {
				compilation.hooks.runtimeRequirementInTree
					.for(requirement)
					.tap(PLUGIN_NAME, handler);
			}
			for (const requirement of [
				RuntimeGlobals.ensureChunkHandlers,
				RuntimeGlobals.chunkCallback,
				RuntimeGlobals.hmrDownloadUpdateHandlers,
				RuntimeGlobals.prefetchChunkHandlers,
				RuntimeGlobals.preloadChunkHandlers
			]) {
				compilation.hooks.runtimeRequirementInTree
					.for(requirement)
					.tap(PLUGIN_NAME, installHandler);
			}

			compilation.hooks.runtimeRequirementInTree
				.for(RuntimeGlobals.ensureChunkHandlers)
				.tap(PLUGIN_NAME, (chunk, set) => {
					if (!isEnabledForChunk(chunk)) return;
					set.add(RuntimeGlobals.publicPath);
					set.add(RuntimeGlobals.loadScript);
					set.add(RuntimeGlobals.getChunkScriptFilename);
				});
			compilation.hooks.runtimeRequirementInTree
				.for(RuntimeGlobals.hmrDownloadUpdateHandlers)
				.tap(PLUGIN_NAME, (chunk, set) => {
					if (!isEnabledForChunk(chunk)) return;
					set.add(RuntimeGlobals.publicPath);
					set.add(RuntimeGlobals.loadScript);
					set.add(RuntimeGlobals.getChunkUpdateScriptFilename);
					set.add(RuntimeGlobals.moduleCache);
					set.add(RuntimeGlobals.hmrModuleData);
					set.add(RuntimeGlobals.moduleFactoriesAddOnly);
				});
			compilation.hooks.runtimeRequirementInTree
				.for(RuntimeGlobals.hmrDownloadManifest)
				.tap(PLUGIN_NAME, (chunk, set) => {
					if (!isEnabledForChunk(chunk)) return;
					set.add(RuntimeGlobals.publicPath);
					set.add(RuntimeGlobals.getUpdateManifestFilename);
				});
		});
	}
}

module.exports = JsonpChunkLoadingPlugin;