webpack.config.prod.js

// @remove-on-eject-begin
/**
 * Copyright (c) 2015-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
// @remove-on-eject-end
'use strict';

const path = require('path');
const webpack = require('webpack');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const TerserPlugin = require('terser-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const ManifestPlugin = require('webpack-manifest-plugin');
const InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
const SWPrecacheWebpackPlugin = require('sw-precache-webpack-plugin');
const ModuleScopePlugin = require('react-dev-utils/ModuleScopePlugin');
const paths = require('./paths');
const getClientEnvironment = require('./env');
const { loaders } = require('./webpack.base');

const TsconfigPathsPlugin = require('tsconfig-paths-webpack-plugin');

// Webpack uses `publicPath` to determine where the app is being served from.
// It requires a trailing slash, or the file assets will get an incorrect path.
const publicPath = paths.servedPath;

// Source maps are resource heavy and can cause out of memory issue for large source files.
const shouldUseSourceMap = process.env.GENERATE_SOURCEMAP !== 'false';
// `publicUrl` is just like `publicPath`, but we will provide it to our app
// as %PUBLIC_URL% in `index.html` and `process.env.PUBLIC_URL` in JavaScript.
// Omit trailing slash as %PUBLIC_URL%/xyz looks better than %PUBLIC_URL%xyz.
const publicUrl = publicPath.slice(0, -1);
// Get environment variables to inject into our app.
const env = getClientEnvironment(publicUrl);

// Assert this just to be safe.
// Development builds of React are slow and not intended for production.
if (env.stringified['process.env'].NODE_ENV !== '"production"') {
  throw new Error('Production builds must have NODE_ENV=production.');
}

// This is the production configuration.
// It compiles slowly and is focused on producing a fast and minimal bundle.
// The development configuration is different and lives in a separate file.
module.exports = {
  mode: 'production',
  // Don't attempt to continue if there are any errors.
  bail: true,
  // We generate sourcemaps in production. This is slow but gives good results.
  // You can exclude the *.map files from the build during deployment.
  devtool: shouldUseSourceMap ? 'source-map' : false,
  entry: [
    // Include your app's code
    paths.appIndexJs
  ],
  output: {
    // The build folder.
    path: paths.appBuild,
    // Generated JS file names (with nested folders).
    // There will be one main bundle, and one file per asynchronous chunk.
    // We don't currently advertise code splitting but Webpack supports it.
    filename: 'static/js/[name].[chunkhash:8].js',
    chunkFilename: 'static/js/[name].[chunkhash:8].chunk.js',
    // We inferred the "public path" (such as / or /my-project) from homepage.
    publicPath: publicPath,
    // Point sourcemap entries to original disk location (format as URL on Windows)
    devtoolModuleFilenameTemplate: (info) =>
      path.relative(paths.appSrc, info.absoluteResourcePath).replace(/\\/g, '/')
  },
  optimization: {
    minimizer: [
      new TerserPlugin({
        terserOptions: {
          parse: {
            // we want uglify-js to parse ecma 8 code. However, we don't want it
            // to apply any minfication steps that turns valid ecma 5 code
            // into invalid ecma 5 code. This is why the 'compress' and 'output'
            // sections only apply transformations that are ecma 5 safe
            // https://github.com/facebook/create-react-app/pull/4234
            ecma: 8
          },
          compress: {
            ecma: 5,
            warnings: false,
            // Disabled because of an issue with Uglify breaking seemingly valid code:
            // https://github.com/facebook/create-react-app/issues/2376
            // Pending further investigation:
            // https://github.com/mishoo/UglifyJS2/issues/2011
            comparisons: false
          },
          mangle: {
            safari10: true
          },
          output: {
            ecma: 5,
            comments: false,
            // Turned on because emoji and regex is not minified properly using default
            // https://github.com/facebook/create-react-app/issues/2488
            ascii_only: true
          }
        },
        // Use multi-process parallel running to improve the build speed
        // Default number of concurrent runs: os.cpus().length - 1
        parallel: true,
        // Enable file caching
        cache: true,
        sourceMap: shouldUseSourceMap
      }),
      new OptimizeCSSAssetsPlugin()
    ],
    // Automatically split vendor and commons
    // https://twitter.com/wSokra/status/969633336732905474
    // https://medium.com/webpack/webpack-4-code-splitting-chunk-graph-and-the-splitchunks-optimization-be739a861366
    splitChunks: {
      chunks: 'all',
      name: false,
    },
    // Keep the runtime chunk seperated to enable long term caching
    // https://twitter.com/wSokra/status/969679223278505985
    runtimeChunk: true,
  },
  resolve: {
    // This allows you to set a fallback for where Webpack should look for modules.
    // We placed these paths second because we want `node_modules` to "win"
    // if there are any conflicts. This matches Node resolution mechanism.
    // https://github.com/facebookincubator/create-react-app/issues/253
    modules: ['node_modules', paths.appSrc, paths.appNodeModules].concat(
      // It is guaranteed to exist because we tweak it in `env.js`
      process.env.NODE_PATH.split(path.delimiter).filter(Boolean)
    ),
    // These are the reasonable defaults supported by the Node ecosystem.
    // We also include JSX as a common component filename extension to support
    // some tools, although we do not recommend using it, see:
    // https://github.com/facebookincubator/create-react-app/issues/290
    // `web` extension prefixes have been added for better support
    // for React Native Web.
    extensions: [
      '.mjs',
      '.web.ts',
      '.ts',
      '.web.tsx',
      '.tsx',
      '.web.js',
      '.js',
      '.json',
      '.web.jsx',
      '.jsx',
      '.scss'
    ],
    alias: {
      // @remove-on-eject-end
      // Support React Native Web
      // https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
      'react-native': 'react-native-web'
    },
    plugins: [
      // Prevents users from importing files from outside of src/ (or node_modules/).
      // This often causes confusion because we only process files within src/ with babel.
      // To fix this, we prevent you from importing files out of src/ -- if you'd like to,
      // please link the files into your node_modules/ and let module-resolution kick in.
      // Make sure your source files are compiled, as they will not be processed in any way.
      new ModuleScopePlugin(paths.appSrc, [paths.appPackageJson]),
      new TsconfigPathsPlugin({ configFile: paths.appTsConfig })
    ]
  },
  module: {
    strictExportPresence: true,
    rules: [
      // Disable require.ensure as it's not a standard language feature.
      { parser: { requireEnsure: false } },
      {
        // "oneOf" will traverse all following loaders until one will
        // match the requirements. When no loader matches it will fall
        // back to the "file" loader at the end of the loader list.
        oneOf: loaders
      }
    ]
  },
  plugins: [
    // Generates an `index.html` file with the <script> injected.
    new HtmlWebpackPlugin({
      inject: true,
      template: paths.appHtml,
      minify: {
        removeComments: true,
        collapseWhitespace: true,
        removeRedundantAttributes: true,
        useShortDoctype: true,
        removeEmptyAttributes: true,
        removeStyleLinkTypeAttributes: true,
        keepClosingSlash: true,
        minifyJS: true,
        minifyCSS: true,
        minifyURLs: true
      }
    }),
    // Makes some environment variables available in index.html.
    // The public URL is available as %PUBLIC_URL% in index.html, e.g.:
    // <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">
    // In production, it will be an empty string unless you specify "homepage"
    // in `package.json`, in which case it will be the pathname of that URL.
    new InterpolateHtmlPlugin(HtmlWebpackPlugin, env.raw),
    // Makes some environment variables available to the JS code, for example:
    // if (process.env.NODE_ENV === 'production') { ... }. See `./env.js`.
    // It is absolutely essential that NODE_ENV was set to production here.
    // Otherwise React will be compiled in the very slow development mode.
    new webpack.DefinePlugin(env.stringified),
    new MiniCssExtractPlugin({
      // Options similar to the same options in webpackOptions.output
      // both options are optional
      filename: 'static/css/[name].[contenthash:8].css',
      chunkFilename: 'static/css/[name].[contenthash:8].chunk.css'
    }),
    // Generate a manifest file which contains a mapping of all asset filenames
    // to their corresponding output file so that tools can pick it up without
    // having to parse `index.html`.
    new ManifestPlugin({
      fileName: 'asset-manifest.json',
      publicPath: publicPath
    }),
    // Generate a service worker script that will precache, and keep up to date,
    // the HTML & assets that are part of the Webpack build.
    new SWPrecacheWebpackPlugin({
      // By default, a cache-busting query parameter is appended to requests
      // used to populate the caches, to ensure the responses are fresh.
      // If a URL is already hashed by Webpack, then there is no concern
      // about it being stale, and the cache-busting can be skipped.
      dontCacheBustUrlsMatching: /\.\w{8}\./,
      filename: 'service-worker.js',
      logger(message) {
        if (message.indexOf('Total precache size is') === 0) {
          // This message occurs for every build and is a bit too noisy.
          return;
        }
        if (message.indexOf('Skipping static resource') === 0) {
          // This message obscures real errors so we ignore it.
          // https://github.com/facebook/create-react-app/issues/2612
          return;
        }
        console.log(message);
      },
      minify: true,
      // Don't precache sourcemaps (they're large) and build asset manifest:
      staticFileGlobsIgnorePatterns: [/\.map$/, /asset-manifest\.json$/]
      // `navigateFallback` and `navigateFallbackWhitelist` are disabled by default; see
      // https://github.com/facebook/create-react-app/blob/master/packages/react-scripts/template/README.md#service-worker-considerations
      // navigateFallback: publicUrl + '/index.html',
      // navigateFallbackWhitelist: [/^(?!\/__).*/],
    }),
    // Moment.js is an extremely popular library that bundles large locale files
    // by default due to how Webpack interprets its code. This is a practical
    // solution that requires the user to opt into importing specific locales.
    // https://github.com/jmblog/how-to-optimize-momentjs-with-webpack
    // You can remove this if you don't use Moment.js:
    new webpack.IgnorePlugin(/^\.\/locale$/, /moment$/)
  ],
  // Some libraries import Node modules but don't use them in the browser.
  // Tell Webpack to provide empty mocks for them so importing them works.
  node: {
    dgram: 'empty',
    fs: 'empty',
    net: 'empty',
    tls: 'empty',
    child_process: 'empty'
  },
  // Turn off performance processing because we utilize
  // our own hints via the FileSizeReporter
  performance: false
};