webpack-bundle-analyzer
Version:
Webpack plugin and CLI utility that represents bundle content as convenient interactive zoomable treemap
255 lines (246 loc) • 9.73 kB
JavaScript
;
const fs = require('fs');
const path = require('path');
const {
parseChunked
} = require('@discoveryjs/json-ext');
const Logger = require('./Logger');
const Folder = require('./tree/Folder').default;
const {
parseBundle
} = require('./parseUtils');
const {
createAssetsFilter
} = require('./utils');
const {
getCompressedSize
} = require('./sizeUtils');
const FILENAME_QUERY_REGEXP = /\?.*$/u;
const FILENAME_EXTENSIONS = /\.(js|mjs|cjs|bundle)$/iu;
module.exports = {
getViewerData,
readStatsFromFile
};
function getViewerData(bundleStats, bundleDir, opts) {
const {
logger = new Logger(),
compressionAlgorithm,
excludeAssets = null
} = opts || {};
const isAssetIncluded = createAssetsFilter(excludeAssets);
// Sometimes all the information is located in `children` array (e.g. problem in #10)
if ((bundleStats.assets == null || bundleStats.assets.length === 0) && bundleStats.children && bundleStats.children.length > 0) {
const {
children
} = bundleStats;
bundleStats = bundleStats.children[0];
// Sometimes if there are additional child chunks produced add them as child assets,
// leave the 1st one as that is considered the 'root' asset.
for (let i = 1; i < children.length; i++) {
children[i].assets.forEach(asset => {
asset.isChild = true;
bundleStats.assets.push(asset);
});
}
} else if (bundleStats.children && bundleStats.children.length > 0) {
// Sometimes if there are additional child chunks produced add them as child assets
bundleStats.children.forEach(child => {
child.assets.forEach(asset => {
asset.isChild = true;
bundleStats.assets.push(asset);
});
});
}
// Picking only `*.js, *.cjs or *.mjs` assets from bundle that has non-empty `chunks` array
bundleStats.assets = (bundleStats.assets || []).filter(asset => {
// Filter out non 'asset' type asset if type is provided (Webpack 5 add a type to indicate asset types)
if (asset.type && asset.type !== 'asset') {
return false;
}
// Removing query part from filename (yes, somebody uses it for some reason and Webpack supports it)
// See #22
asset.name = asset.name.replace(FILENAME_QUERY_REGEXP, '');
return FILENAME_EXTENSIONS.test(asset.name) && asset.chunks.length > 0 && isAssetIncluded(asset.name);
});
// Trying to parse bundle assets and get real module sizes if `bundleDir` is provided
let bundlesSources = null;
let parsedModules = null;
if (bundleDir) {
bundlesSources = {};
parsedModules = {};
for (const statAsset of bundleStats.assets) {
const assetFile = path.join(bundleDir, statAsset.name);
let bundleInfo;
try {
bundleInfo = parseBundle(assetFile, {
sourceType: statAsset.info.javascriptModule ? 'module' : 'script'
});
} catch (err) {
const msg = err.code === 'ENOENT' ? 'no such file' : err.message;
logger.warn(`Error parsing bundle asset "${assetFile}": ${msg}`, {
cause: err
});
continue;
}
bundlesSources[statAsset.name] = {
src: bundleInfo.src,
runtimeSrc: bundleInfo.runtimeSrc
};
Object.assign(parsedModules, bundleInfo.modules);
}
if (Object.keys(bundlesSources).length === 0) {
bundlesSources = null;
parsedModules = null;
logger.warn('\nNo bundles were parsed. Analyzer will show only original module sizes from stats file.\n');
}
}
const assets = bundleStats.assets.reduce((result, statAsset) => {
// If asset is a childAsset, then calculate appropriate bundle modules by looking through stats.children
const assetBundles = statAsset.isChild ? getChildAssetBundles(bundleStats, statAsset.name) : bundleStats;
const modules = assetBundles ? getBundleModules(assetBundles) : [];
const asset = result[statAsset.name] = {
size: statAsset.size
};
const assetSources = bundlesSources && Object.prototype.hasOwnProperty.call(bundlesSources, statAsset.name) ? bundlesSources[statAsset.name] : null;
if (assetSources) {
asset.parsedSize = Buffer.byteLength(assetSources.src);
if (compressionAlgorithm === 'gzip') asset.gzipSize = getCompressedSize('gzip', assetSources.src);
if (compressionAlgorithm === 'brotli') asset.brotliSize = getCompressedSize('brotli', assetSources.src);
if (compressionAlgorithm === 'zstd') asset.zstdSize = getCompressedSize('zstd', assetSources.src);
}
// Picking modules from current bundle script
let assetModules = (modules || []).filter(statModule => assetHasModule(statAsset, statModule));
// Adding parsed sources
if (parsedModules) {
const unparsedEntryModules = [];
for (const statModule of assetModules) {
if (parsedModules[statModule.id]) {
statModule.parsedSrc = parsedModules[statModule.id];
} else if (isEntryModule(statModule)) {
unparsedEntryModules.push(statModule);
}
}
// Webpack 5 changed bundle format and now entry modules are concatenated and located at the end of it.
// Because of this they basically become a concatenated module, for which we can't even precisely determine its
// parsed source as it's located in the same scope as all Webpack runtime helpers.
if (unparsedEntryModules.length && assetSources) {
if (unparsedEntryModules.length === 1) {
// So if there is only one entry we consider its parsed source to be all the bundle code excluding code
// from parsed modules.
unparsedEntryModules[0].parsedSrc = assetSources.runtimeSrc;
} else {
// If there are multiple entry points we move all of them under synthetic concatenated module.
assetModules = (assetModules || []).filter(mod => !unparsedEntryModules.includes(mod));
assetModules.unshift({
identifier: './entry modules',
name: './entry modules',
modules: unparsedEntryModules,
size: unparsedEntryModules.reduce((totalSize, module) => totalSize + module.size, 0),
parsedSrc: assetSources.runtimeSrc
});
}
}
}
asset.modules = assetModules;
asset.tree = createModulesTree(asset.modules, {
compressionAlgorithm
});
return result;
}, {});
const chunkToInitialByEntrypoint = getChunkToInitialByEntrypoint(bundleStats);
return Object.entries(assets).map(([filename, asset]) => ({
label: filename,
isAsset: true,
// Not using `asset.size` here provided by Webpack because it can be very confusing when `UglifyJsPlugin` is used.
// In this case all module sizes from stats file will represent unminified module sizes, but `asset.size` will
// be the size of minified bundle.
// Using `asset.size` only if current asset doesn't contain any modules (resulting size equals 0)
statSize: asset.tree.size || asset.size,
parsedSize: asset.parsedSize,
gzipSize: asset.gzipSize,
brotliSize: asset.brotliSize,
zstdSize: asset.zstdSize,
groups: Object.values(asset.tree.children).map(i => i.toChartData()),
isInitialByEntrypoint: chunkToInitialByEntrypoint[filename] ?? {}
}));
}
function readStatsFromFile(filename) {
return parseChunked(fs.createReadStream(filename, {
encoding: 'utf8'
}));
}
function getChildAssetBundles(bundleStats, assetName) {
return flatten((bundleStats.children || []).find(c => Object.values(c.assetsByChunkName))).includes(assetName);
}
function getBundleModules(bundleStats) {
const seenIds = new Set();
return flatten((bundleStats.chunks?.map(chunk => chunk.modules) || []).concat(bundleStats.modules).filter(Boolean)).filter(mod => {
// Filtering out Webpack's runtime modules as they don't have ids and can't be parsed (introduced in Webpack 5)
if (isRuntimeModule(mod)) {
return false;
}
if (seenIds.has(mod.id)) {
return false;
}
seenIds.add(mod.id);
return true;
});
}
function assetHasModule(statAsset, statModule) {
// Checking if this module is the part of asset chunks
return (statModule.chunks || []).some(moduleChunk => statAsset.chunks.includes(moduleChunk));
}
function isEntryModule(statModule) {
return statModule.depth === 0;
}
function isRuntimeModule(statModule) {
return statModule.moduleType === 'runtime';
}
function createModulesTree(modules, opts) {
const root = new Folder('.', opts);
modules.forEach(module => root.addModule(module));
root.mergeNestedFolders();
return root;
}
function getChunkToInitialByEntrypoint(bundleStats) {
if (bundleStats == null) {
return {};
}
const chunkToEntrypointInititalMap = {};
Object.values(bundleStats.entrypoints || {}).forEach(entrypoint => {
for (const asset of entrypoint.assets) {
chunkToEntrypointInititalMap[asset.name] = chunkToEntrypointInititalMap[asset.name] ?? {};
chunkToEntrypointInititalMap[asset.name][entrypoint.name] = true;
}
});
return chunkToEntrypointInititalMap;
}
;
/**
* arr-flatten <https://github.com/jonschlinkert/arr-flatten>
*
* Copyright (c) 2014-2017, Jon Schlinkert.
* Released under the MIT License.
*
* Modified by Sukka <https://skk.moe>
*
* Replace recursively flatten with one-level deep flatten to match lodash.flatten
*
* TODO: replace with Array.prototype.flat once Node.js 10 support is dropped
*/
function flatten(arr) {
if (!arr) return [];
const len = arr.length;
if (!len) return [];
let cur;
const res = [];
for (let i = 0; i < len; i++) {
cur = arr[i];
if (Array.isArray(cur)) {
res.push(...cur);
} else {
res.push(cur);
}
}
return res;
}