webpack/lib/SourceMapDevToolPlugin.js

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

"use strict";

const asyncLib = require("neo-async");
const validateOptions = require("schema-utils");
const { ConcatSource, RawSource } = require("webpack-sources");
const ModuleFilenameHelpers = require("./ModuleFilenameHelpers");
const ProgressPlugin = require("./ProgressPlugin");
const SourceMapDevToolModuleOptionsPlugin = require("./SourceMapDevToolModuleOptionsPlugin");
const getLazyHashedEtag = require("./cache/getLazyHashedEtag");
const createHash = require("./util/createHash");
const { relative, dirname } = require("./util/fs");
const { absolutify } = require("./util/identifier");

const schema = require("../schemas/plugins/SourceMapDevToolPlugin.json");

/** @typedef {import("source-map").RawSourceMap} SourceMap */
/** @typedef {import("webpack-sources").Source} Source */
/** @typedef {import("../declarations/plugins/SourceMapDevToolPlugin").SourceMapDevToolPluginOptions} SourceMapDevToolPluginOptions */
/** @typedef {import("./Cache").Etag} Etag */
/** @typedef {import("./Chunk")} Chunk */
/** @typedef {import("./Compilation")} Compilation */
/** @typedef {import("./Compiler")} Compiler */
/** @typedef {import("./Module")} Module */
/** @typedef {import("./util/Hash")} Hash */

/**
 * @typedef {object} SourceMapTask
 * @property {Source} asset
 * @property {(string | Module)[]} modules
 * @property {string} source
 * @property {string} file
 * @property {SourceMap} sourceMap
 * @property {string} cacheIdent cache identifier
 * @property {Etag} cacheETag cache ETag
 */

/**
 * Creating {@link SourceMapTask} for given file
 * @param {string} file current compiled file
 * @param {Source} asset the asset
 * @param {SourceMapDevToolPluginOptions} options source map options
 * @param {Compilation} compilation compilation instance
 * @param {string} cacheIdent cache identifier
 * @param {Etag} cacheETag cache ETag
 * @returns {SourceMapTask | undefined} created task instance or `undefined`
 */
const getTaskForFile = (
	file,
	asset,
	options,
	compilation,
	cacheIdent,
	cacheETag
) => {
	let source;
	/** @type {SourceMap} */
	let sourceMap;
	/**
	 * Check if asset can build source map
	 */
	if (asset.sourceAndMap) {
		const sourceAndMap = asset.sourceAndMap(options);
		sourceMap = /** @type {SourceMap} */ (sourceAndMap.map);
		source = sourceAndMap.source;
	} else {
		sourceMap = /** @type {SourceMap} */ (asset.map(options));
		source = asset.source();
	}
	if (!sourceMap || typeof source !== "string") return;
	const context = compilation.options.context;
	const root = compilation.compiler.root;
	const modules = sourceMap.sources.map(source => {
		if (!source.startsWith("webpack://")) return source;
		source = absolutify(context, source.slice(10), root);
		const module = compilation.findModule(source);
		return module || source;
	});

	return {
		file,
		asset,
		source,
		sourceMap,
		modules,
		cacheIdent,
		cacheETag
	};
};

class SourceMapDevToolPlugin {
	/**
	 * @param {SourceMapDevToolPluginOptions} [options] options object
	 * @throws {Error} throws error, if got more than 1 arguments
	 */
	constructor(options = {}) {
		validateOptions(schema, options, {
			name: "SourceMap DevTool Plugin",
			baseDataPath: "options"
		});

		/** @type {string | false} */
		this.sourceMapFilename = options.filename;
		/** @type {string | false} */
		this.sourceMappingURLComment =
			options.append === false
				? false
				: options.append || "\n//# source" + "MappingURL=[url]";
		/** @type {string | Function} */
		this.moduleFilenameTemplate =
			options.moduleFilenameTemplate || "webpack://[namespace]/[resourcePath]";
		/** @type {string | Function} */
		this.fallbackModuleFilenameTemplate =
			options.fallbackModuleFilenameTemplate ||
			"webpack://[namespace]/[resourcePath]?[hash]";
		/** @type {string} */
		this.namespace = options.namespace || "";
		/** @type {SourceMapDevToolPluginOptions} */
		this.options = options;
	}

	/**
	 * Apply compiler
	 * @param {Compiler} compiler compiler instance
	 * @returns {void}
	 */
	apply(compiler) {
		const outputFs = compiler.outputFileSystem;
		const sourceMapFilename = this.sourceMapFilename;
		const sourceMappingURLComment = this.sourceMappingURLComment;
		const moduleFilenameTemplate = this.moduleFilenameTemplate;
		const namespace = this.namespace;
		const fallbackModuleFilenameTemplate = this.fallbackModuleFilenameTemplate;
		const requestShortener = compiler.requestShortener;
		const options = this.options;
		options.test = options.test || /\.(m?js|css)($|\?)/i;

		const matchObject = ModuleFilenameHelpers.matchObject.bind(
			undefined,
			options
		);

		compiler.hooks.compilation.tap("SourceMapDevToolPlugin", compilation => {
			new SourceMapDevToolModuleOptionsPlugin(options).apply(compilation);

			compilation.hooks.finishAssets.tapAsync(
				"SourceMapDevToolPlugin",
				(assets, callback) => {
					const chunkGraph = compilation.chunkGraph;
					/** @type {Map<string | Module, string>} */
					const moduleToSourceNameMapping = new Map();
					/**
					 * @type {Function}
					 * @returns {void}
					 */
					const reportProgress =
						ProgressPlugin.getReporter(compilation.compiler) || (() => {});

					/** @type {Map<string, Chunk>} */
					const fileToChunk = new Map();
					for (const chunk of compilation.chunks) {
						for (const file of chunk.files) {
							fileToChunk.set(file, chunk);
						}
						for (const file of chunk.auxiliaryFiles) {
							fileToChunk.set(file, chunk);
						}
					}

					/** @type {string[]} */
					const files = [];
					for (const file of Object.keys(assets)) {
						if (matchObject(file)) {
							files.push(file);
						}
					}

					reportProgress(0.0);
					/** @type {SourceMapTask[]} */
					const tasks = [];
					let fileIndex = 0;

					asyncLib.each(
						files,
						(file, callback) => {
							const asset = compilation.getAsset(file).source;
							const cacheIdent = `${compilation.compilerPath}/SourceMapDevToolPlugin/${file}`;
							const cacheETag = getLazyHashedEtag(asset);

							compilation.cache.get(cacheIdent, cacheETag, (err, assets) => {
								if (err) {
									return callback(err);
								}
								/**
								 * If presented in cache, reassigns assets. Cache assets already have source maps.
								 */
								if (assets) {
									for (const cachedFile in assets) {
										if (cachedFile === file) {
											compilation.updateAsset(cachedFile, assets[cachedFile]);
										} else {
											compilation.emitAsset(cachedFile, assets[cachedFile], {
												development: true
											});
										}
										/**
										 * Add file to chunk, if not presented there
										 */
										if (cachedFile !== file) {
											const chunk = fileToChunk.get(file);
											if (chunk !== undefined)
												chunk.auxiliaryFiles.add(cachedFile);
										}
									}

									reportProgress(
										(0.5 * ++fileIndex) / files.length,
										file,
										"restored cached SourceMap"
									);

									return callback();
								}

								reportProgress(
									(0.5 * fileIndex) / files.length,
									file,
									"generate SourceMap"
								);

								/** @type {SourceMapTask | undefined} */
								const task = getTaskForFile(
									file,
									asset,
									options,
									compilation,
									cacheIdent,
									cacheETag
								);

								if (task) {
									const modules = task.modules;

									for (let idx = 0; idx < modules.length; idx++) {
										const module = modules[idx];
										if (!moduleToSourceNameMapping.get(module)) {
											moduleToSourceNameMapping.set(
												module,
												ModuleFilenameHelpers.createFilename(
													module,
													{
														moduleFilenameTemplate: moduleFilenameTemplate,
														namespace: namespace
													},
													{
														requestShortener,
														chunkGraph
													}
												)
											);
										}
									}

									tasks.push(task);
								}

								reportProgress(
									(0.5 * ++fileIndex) / files.length,
									file,
									"generated SourceMap"
								);

								callback();
							});
						},
						err => {
							if (err) {
								return callback(err);
							}

							reportProgress(0.5, "resolve sources");
							/** @type {Set<string>} */
							const usedNamesSet = new Set(moduleToSourceNameMapping.values());
							/** @type {Set<string>} */
							const conflictDetectionSet = new Set();

							/**
							 * all modules in defined order (longest identifier first)
							 * @type {Array<string | Module>}
							 */
							const allModules = Array.from(
								moduleToSourceNameMapping.keys()
							).sort((a, b) => {
								const ai = typeof a === "string" ? a : a.identifier();
								const bi = typeof b === "string" ? b : b.identifier();
								return ai.length - bi.length;
							});

							// find modules with conflicting source names
							for (let idx = 0; idx < allModules.length; idx++) {
								const module = allModules[idx];
								let sourceName = moduleToSourceNameMapping.get(module);
								let hasName = conflictDetectionSet.has(sourceName);
								if (!hasName) {
									conflictDetectionSet.add(sourceName);
									continue;
								}

								// try the fallback name first
								sourceName = ModuleFilenameHelpers.createFilename(
									module,
									{
										moduleFilenameTemplate: fallbackModuleFilenameTemplate,
										namespace: namespace
									},
									{
										requestShortener,
										chunkGraph
									}
								);
								hasName = usedNamesSet.has(sourceName);
								if (!hasName) {
									moduleToSourceNameMapping.set(module, sourceName);
									usedNamesSet.add(sourceName);
									continue;
								}

								// otherwise just append stars until we have a valid name
								while (hasName) {
									sourceName += "*";
									hasName = usedNamesSet.has(sourceName);
								}
								moduleToSourceNameMapping.set(module, sourceName);
								usedNamesSet.add(sourceName);
							}

							let taskIndex = 0;

							asyncLib.each(
								tasks,
								(task, callback) => {
									const assets = Object.create(null);
									const file = task.file;
									const chunk = fileToChunk.get(file);
									const sourceMap = task.sourceMap;
									const source = task.source;
									const modules = task.modules;

									reportProgress(
										0.5 + (0.5 * taskIndex) / tasks.length,
										file,
										"attach SourceMap"
									);

									const moduleFilenames = modules.map(m =>
										moduleToSourceNameMapping.get(m)
									);
									sourceMap.sources = moduleFilenames;
									if (options.noSources) {
										sourceMap.sourcesContent = undefined;
									}
									sourceMap.sourceRoot = options.sourceRoot || "";
									sourceMap.file = file;

									/** @type {string | false} */
									let currentSourceMappingURLComment = sourceMappingURLComment;
									if (
										currentSourceMappingURLComment !== false &&
										/\.css($|\?)/i.test(file)
									) {
										currentSourceMappingURLComment = currentSourceMappingURLComment.replace(
											/^\n\/\/(.*)$/,
											"\n/*$1*/"
										);
									}
									const sourceMapString = JSON.stringify(sourceMap);
									if (sourceMapFilename) {
										let filename = file;
										const pathParams = {
											chunk,
											filename: options.fileContext
												? relative(
														outputFs,
														`/${options.fileContext}`,
														`/${filename}`
												  )
												: filename,
											contentHash: /** @type {string} */ (createHash("md4")
												.update(sourceMapString)
												.digest("hex"))
										};
										let sourceMapFile = compilation.getPath(
											sourceMapFilename,
											pathParams
										);
										const sourceMapUrl = options.publicPath
											? options.publicPath + sourceMapFile
											: relative(
													outputFs,
													dirname(outputFs, `/${file}`),
													`/${sourceMapFile}`
											  );
										/**
										 * Add source map url to compilation asset, if {@link currentSourceMappingURLComment} presented
										 */
										if (currentSourceMappingURLComment !== false) {
											const asset = new ConcatSource(
												new RawSource(source),
												compilation.getPath(
													currentSourceMappingURLComment,
													Object.assign({ url: sourceMapUrl }, pathParams)
												)
											);
											assets[file] = asset;
											compilation.updateAsset(file, asset);
										}
										/**
										 * Add source map file to compilation assets and chunk files
										 */
										const asset = new RawSource(sourceMapString);
										assets[sourceMapFile] = asset;
										compilation.emitAsset(sourceMapFile, asset, {
											development: true
										});
										if (chunk !== undefined)
											chunk.auxiliaryFiles.add(sourceMapFile);
									} else {
										if (currentSourceMappingURLComment === false) {
											throw new Error(
												"SourceMapDevToolPlugin: append can't be false when no filename is provided"
											);
										}
										/**
										 * Add source map as data url to asset
										 */
										const asset = new ConcatSource(
											new RawSource(source),
											currentSourceMappingURLComment
												.replace(/\[map\]/g, () => sourceMapString)
												.replace(
													/\[url\]/g,
													() =>
														`data:application/json;charset=utf-8;base64,${Buffer.from(
															sourceMapString,
															"utf-8"
														).toString("base64")}`
												)
										);
										assets[file] = asset;
										compilation.updateAsset(file, asset);
									}

									compilation.cache.store(
										task.cacheIdent,
										task.cacheETag,
										assets,
										err => {
											reportProgress(
												0.5 + (0.5 * ++taskIndex) / tasks.length,
												task.file,
												"attached SourceMap"
											);

											if (err) {
												return callback(err);
											}
											callback();
										}
									);
								},
								err => {
									reportProgress(1.0);
									callback(err);
								}
							);
						}
					);
				}
			);
		});
	}
}

module.exports = SourceMapDevToolPlugin;