webpack/lib/dependencies/WorkerDependency.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 Ivan Kopeykin @vankop
*/

"use strict";

const Dependency = require("../Dependency");
const RuntimeGlobals = require("../RuntimeGlobals");
const makeSerializable = require("../util/makeSerializable");
const ModuleDependency = require("./ModuleDependency");

/** @typedef {import("webpack-sources").ReplaceSource} ReplaceSource */
/** @typedef {import("../AsyncDependenciesBlock")} AsyncDependenciesBlock */
/** @typedef {import("../Dependency").ReferencedExports} ReferencedExports */
/** @typedef {import("../Dependency").UpdateHashContext} UpdateHashContext */
/** @typedef {import("../DependencyTemplate").DependencyTemplateContext} DependencyTemplateContext */
/** @typedef {import("../Entrypoint")} Entrypoint */
/** @typedef {import("../ModuleGraph")} ModuleGraph */
/** @typedef {import("../javascript/JavascriptParser").Range} Range */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectDeserializerContext} ObjectDeserializerContext */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectSerializerContext} ObjectSerializerContext */
/** @typedef {import("../util/Hash")} Hash */
/** @typedef {import("../util/runtime").RuntimeSpec} RuntimeSpec */

/**
 * Represents the worker dependency runtime component.
 * @typedef {object} WorkerDependencyOptions
 * @property {string=} publicPath public path for the worker
 * @property {boolean=} needNewUrl true when need generate `new URL(...)`, otherwise false
 */

class WorkerDependency extends ModuleDependency {
	/**
	 * Creates an instance of WorkerDependency.
	 * @param {string} request request
	 * @param {Range} range range
	 * @param {WorkerDependencyOptions} workerDependencyOptions options
	 */
	constructor(request, range, workerDependencyOptions) {
		super(request);
		this.range = range;
		// If options are updated, don't forget to update the hash and serialization functions
		/** @type {WorkerDependencyOptions} */
		this.options = workerDependencyOptions;
		/** Cache the hash */
		/** @type {undefined | string} */
		this._hashUpdate = undefined;
	}

	/**
	 * Returns list of exports referenced by this dependency
	 * @param {ModuleGraph} moduleGraph module graph
	 * @param {RuntimeSpec} runtime the runtime for which the module is analysed
	 * @returns {ReferencedExports} referenced exports
	 */
	getReferencedExports(moduleGraph, runtime) {
		return Dependency.NO_EXPORTS_REFERENCED;
	}

	get type() {
		return "new Worker()";
	}

	get category() {
		return "worker";
	}

	/**
	 * Updates the hash with the data contributed by this instance.
	 * @param {Hash} hash hash to be updated
	 * @param {UpdateHashContext} context context
	 * @returns {void}
	 */
	updateHash(hash, context) {
		if (this._hashUpdate === undefined) {
			this._hashUpdate = JSON.stringify(this.options);
		}
		hash.update(this._hashUpdate);
	}

	/**
	 * Serializes this instance into the provided serializer context.
	 * @param {ObjectSerializerContext} context context
	 */
	serialize(context) {
		const { write } = context;
		write(this.options);
		super.serialize(context);
	}

	/**
	 * Restores this instance from the provided deserializer context.
	 * @param {ObjectDeserializerContext} context context
	 */
	deserialize(context) {
		const { read } = context;
		this.options = read();
		super.deserialize(context);
	}
}

WorkerDependency.Template = class WorkerDependencyTemplate extends (
	ModuleDependency.Template
) {
	/**
	 * Applies the plugin by registering its hooks on the compiler.
	 * @param {Dependency} dependency the dependency for which the template should be applied
	 * @param {ReplaceSource} source the current replace source which can be modified
	 * @param {DependencyTemplateContext} templateContext the context object
	 * @returns {void}
	 */
	apply(dependency, source, templateContext) {
		const { chunkGraph, moduleGraph, runtimeRequirements } = templateContext;
		const dep = /** @type {WorkerDependency} */ (dependency);
		const block = /** @type {AsyncDependenciesBlock} */ (
			moduleGraph.getParentBlock(dependency)
		);
		const entrypoint = /** @type {Entrypoint} */ (
			chunkGraph.getBlockChunkGroup(block)
		);
		const chunk = entrypoint.getEntrypointChunk();
		// We use the workerPublicPath option if provided, else we fallback to the RuntimeGlobal publicPath
		const workerImportBaseUrl = dep.options.publicPath
			? `"${dep.options.publicPath}"`
			: RuntimeGlobals.publicPath;

		runtimeRequirements.add(RuntimeGlobals.publicPath);
		runtimeRequirements.add(RuntimeGlobals.baseURI);
		runtimeRequirements.add(RuntimeGlobals.getChunkScriptFilename);

		const workerImportStr = `/* worker import */ ${workerImportBaseUrl} + ${
			RuntimeGlobals.getChunkScriptFilename
		}(${JSON.stringify(chunk.id)}), ${RuntimeGlobals.baseURI}`;

		source.replace(
			dep.range[0],
			dep.range[1] - 1,
			dep.options.needNewUrl ? `new URL(${workerImportStr})` : workerImportStr
		);
	}
};

makeSerializable(WorkerDependency, "webpack/lib/dependencies/WorkerDependency");

module.exports = WorkerDependency;