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("../ChunkGraph")} ChunkGraph */
/** @typedef {import("../Dependency").ReferencedExport} ReferencedExport */
/** @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 */

class WorkerDependency extends ModuleDependency {
	/**
	 * @param {string} request request
	 * @param {Range} range range
	 * @param {object} workerDependencyOptions options
	 * @param {string=} workerDependencyOptions.publicPath public path for the worker
	 */
	constructor(request, range, workerDependencyOptions) {
		super(request);
		this.range = range;
		// If options are updated, don't forget to update the hash and serialization functions
		this.options = workerDependencyOptions;
		/** Cache the hash */
		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 {(string[] | ReferencedExport)[]} referenced exports
	 */
	getReferencedExports(moduleGraph, runtime) {
		return Dependency.NO_EXPORTS_REFERENCED;
	}

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

	get category() {
		return "worker";
	}

	/**
	 * Update the hash
	 * @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);
	}

	/**
	 * @param {ObjectSerializerContext} context context
	 */
	serialize(context) {
		const { write } = context;
		write(this.options);
		super.serialize(context);
	}

	/**
	 * @param {ObjectDeserializerContext} context context
	 */
	deserialize(context) {
		const { read } = context;
		this.options = read();
		super.deserialize(context);
	}
}

WorkerDependency.Template = class WorkerDependencyTemplate extends (
	ModuleDependency.Template
) {
	/**
	 * @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);

		source.replace(
			dep.range[0],
			dep.range[1] - 1,
			`/* worker import */ ${workerImportBaseUrl} + ${
				RuntimeGlobals.getChunkScriptFilename
			}(${JSON.stringify(chunk.id)}), ${RuntimeGlobals.baseURI}`
		);
	}
};

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

module.exports = WorkerDependency;