webpack/lib/DelegatedModule.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 { OriginalSource, RawSource } = require("webpack-sources");
const Module = require("./Module");
const {
	JAVASCRIPT_TYPE,
	JAVASCRIPT_TYPES
} = require("./ModuleSourceTypeConstants");
const { JAVASCRIPT_MODULE_TYPE_DYNAMIC } = require("./ModuleTypeConstants");
const RuntimeGlobals = require("./RuntimeGlobals");
const DelegatedSourceDependency = require("./dependencies/DelegatedSourceDependency");
const StaticExportsDependency = require("./dependencies/StaticExportsDependency");
const makeSerializable = require("./util/makeSerializable");

/** @typedef {import("../declarations/plugins/DllReferencePlugin").DllReferencePluginOptions} DllReferencePluginOptions */
/** @typedef {import("./config/defaults").WebpackOptionsNormalizedWithDefaults} WebpackOptions */
/** @typedef {import("./Compilation")} Compilation */
/** @typedef {import("./Dependency").UpdateHashContext} UpdateHashContext */
/** @typedef {import("./Generator").SourceTypes} SourceTypes */
/** @typedef {import("./LibManifestPlugin").ManifestModuleData} ManifestModuleData */
/** @typedef {import("./Module").ModuleId} ModuleId */
/** @typedef {import("./Module").BuildCallback} BuildCallback */
/** @typedef {import("./Module").BuildMeta} BuildMeta */
/** @typedef {import("./Module").CodeGenerationContext} CodeGenerationContext */
/** @typedef {import("./Module").CodeGenerationResult} CodeGenerationResult */
/** @typedef {import("./Module").LibIdentOptions} LibIdentOptions */
/** @typedef {import("./Module").LibIdent} LibIdent */
/** @typedef {import("./Module").NeedBuildCallback} NeedBuildCallback */
/** @typedef {import("./Module").NeedBuildContext} NeedBuildContext */
/** @typedef {import("./Module").Sources} Sources */
/** @typedef {import("./Module").RuntimeRequirements} RuntimeRequirements */
/** @typedef {import("./RequestShortener")} RequestShortener */
/** @typedef {import("./ResolverFactory").ResolverWithOptions} ResolverWithOptions */
/** @typedef {import("./serialization/ObjectMiddleware").ObjectDeserializerContext} ObjectDeserializerContext */
/** @typedef {import("./serialization/ObjectMiddleware").ObjectSerializerContext} ObjectSerializerContext */
/** @typedef {import("./dependencies/StaticExportsDependency").Exports} Exports */
/** @typedef {import("./util/Hash")} Hash */
/** @typedef {import("./util/fs").InputFileSystem} InputFileSystem */

/** @typedef {string} DelegatedModuleSourceRequest */

/** @typedef {NonNullable<DllReferencePluginOptions["type"]>} DelegatedModuleType */

/**
 * Defines the delegated module data type used by this module.
 * @typedef {object} DelegatedModuleData
 * @property {BuildMeta=} buildMeta build meta
 * @property {Exports=} exports exports
 * @property {ModuleId} id module id
 */

const RUNTIME_REQUIREMENTS = new Set([
	RuntimeGlobals.module,
	RuntimeGlobals.require
]);

class DelegatedModule extends Module {
	/**
	 * Creates an instance of DelegatedModule.
	 * @param {DelegatedModuleSourceRequest} sourceRequest source request
	 * @param {DelegatedModuleData} data data
	 * @param {DelegatedModuleType} type type
	 * @param {string} userRequest user request
	 * @param {string | Module} originalRequest original request
	 */
	constructor(sourceRequest, data, type, userRequest, originalRequest) {
		super(JAVASCRIPT_MODULE_TYPE_DYNAMIC, null);

		// Info from Factory
		this.sourceRequest = sourceRequest;
		this.request = data.id;
		this.delegationType = type;
		this.userRequest = userRequest;
		this.originalRequest = originalRequest;
		this.delegateData = data;

		// Build info
		/** @type {undefined | DelegatedSourceDependency} */
		this.delegatedSourceDependency = undefined;
	}

	/**
	 * Returns the source types this module can generate.
	 * @returns {SourceTypes} types available (do not mutate)
	 */
	getSourceTypes() {
		return JAVASCRIPT_TYPES;
	}

	/**
	 * Gets the library identifier.
	 * @param {LibIdentOptions} options options
	 * @returns {LibIdent | null} an identifier for library inclusion
	 */
	libIdent(options) {
		return typeof this.originalRequest === "string"
			? this.originalRequest
			: this.originalRequest.libIdent(options);
	}

	/**
	 * Returns the unique identifier used to reference this module.
	 * @returns {string} a unique identifier of the module
	 */
	identifier() {
		return `delegated ${JSON.stringify(this.request)} from ${
			this.sourceRequest
		}`;
	}

	/**
	 * Returns a human-readable identifier for this module.
	 * @param {RequestShortener} requestShortener the request shortener
	 * @returns {string} a user readable identifier of the module
	 */
	readableIdentifier(requestShortener) {
		return `delegated ${this.userRequest} from ${this.sourceRequest}`;
	}

	/**
	 * Checks whether the module needs to be rebuilt for the current build state.
	 * @param {NeedBuildContext} context context info
	 * @param {NeedBuildCallback} callback callback function, returns true, if the module needs a rebuild
	 * @returns {void}
	 */
	needBuild(context, callback) {
		return callback(null, !this.buildMeta);
	}

	/**
	 * Builds the module using the provided compilation context.
	 * @param {WebpackOptions} options webpack options
	 * @param {Compilation} compilation the compilation
	 * @param {ResolverWithOptions} resolver the resolver
	 * @param {InputFileSystem} fs the file system
	 * @param {BuildCallback} callback callback function
	 * @returns {void}
	 */
	build(options, compilation, resolver, fs, callback) {
		const delegateData = /** @type {ManifestModuleData} */ (this.delegateData);
		this.buildMeta = { ...delegateData.buildMeta };
		this.buildInfo = {};
		this.dependencies.length = 0;
		this.delegatedSourceDependency = new DelegatedSourceDependency(
			this.sourceRequest
		);
		this.addDependency(this.delegatedSourceDependency);
		this.addDependency(
			new StaticExportsDependency(delegateData.exports || true, false)
		);
		callback();
	}

	/**
	 * Generates code and runtime requirements for this module.
	 * @param {CodeGenerationContext} context context for code generation
	 * @returns {CodeGenerationResult} result
	 */
	codeGeneration({ runtimeTemplate, moduleGraph, chunkGraph }) {
		const dep = /** @type {DelegatedSourceDependency} */ (this.dependencies[0]);
		const sourceModule = moduleGraph.getModule(dep);
		/** @type {string} */
		let str;

		if (!sourceModule) {
			str = runtimeTemplate.throwMissingModuleErrorBlock({
				request: this.sourceRequest
			});
		} else {
			str = `module.exports = (${runtimeTemplate.moduleExports({
				module: sourceModule,
				chunkGraph,
				request: dep.request,
				/** @type {RuntimeRequirements} */
				runtimeRequirements: new Set()
			})})`;

			switch (this.delegationType) {
				case "require":
					str += `(${JSON.stringify(this.request)})`;
					break;
				case "object":
					str += `[${JSON.stringify(this.request)}]`;
					break;
			}

			str += ";";
		}

		/** @type {Sources} */
		const sources = new Map();
		if (this.useSourceMap || this.useSimpleSourceMap) {
			sources.set(JAVASCRIPT_TYPE, new OriginalSource(str, this.identifier()));
		} else {
			sources.set(JAVASCRIPT_TYPE, new RawSource(str));
		}

		return {
			sources,
			runtimeRequirements: RUNTIME_REQUIREMENTS
		};
	}

	/**
	 * Returns the estimated size for the requested source type.
	 * @param {string=} type the source type for which the size should be estimated
	 * @returns {number} the estimated size of the module (must be non-zero)
	 */
	size(type) {
		return 42;
	}

	/**
	 * Updates the hash with the data contributed by this instance.
	 * @param {Hash} hash the hash used to track dependencies
	 * @param {UpdateHashContext} context context
	 * @returns {void}
	 */
	updateHash(hash, context) {
		hash.update(this.delegationType);
		hash.update(JSON.stringify(this.request));
		super.updateHash(hash, context);
	}

	/**
	 * Serializes this instance into the provided serializer context.
	 * @param {ObjectSerializerContext} context context
	 */
	serialize(context) {
		const { write } = context;
		// constructor
		write(this.sourceRequest);
		write(this.delegateData);
		write(this.delegationType);
		write(this.userRequest);
		write(this.originalRequest);
		super.serialize(context);
	}

	/**
	 * Restores this instance from the provided deserializer context.
	 * @param {ObjectDeserializerContext} context context\
	 * @returns {DelegatedModule} DelegatedModule
	 */
	static deserialize(context) {
		const { read } = context;
		const obj = new DelegatedModule(
			read(), // sourceRequest
			read(), // delegateData
			read(), // delegationType
			read(), // userRequest
			read() // originalRequest
		);
		obj.deserialize(context);
		return obj;
	}

	/**
	 * Assuming this module is in the cache. Update the (cached) module with
	 * the fresh module from the factory. Usually updates internal references
	 * and properties.
	 * @param {Module} module fresh module
	 * @returns {void}
	 */
	updateCacheModule(module) {
		super.updateCacheModule(module);
		const m = /** @type {DelegatedModule} */ (module);
		this.delegationType = m.delegationType;
		this.userRequest = m.userRequest;
		this.originalRequest = m.originalRequest;
		this.delegateData = m.delegateData;
	}

	/**
	 * Assuming this module is in the cache. Remove internal references to allow freeing some memory.
	 */
	cleanupForCache() {
		super.cleanupForCache();
		this.delegateData =
			/** @type {EXPECTED_ANY} */
			(undefined);
	}
}

makeSerializable(DelegatedModule, "webpack/lib/DelegatedModule");

module.exports = DelegatedModule;