webpack.config.js

const fs = require('fs');
const path = require('path');
const webpack = require('webpack');
const resolve = require('resolve');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CaseSensitivePathsPlugin = require('case-sensitive-paths-webpack-plugin');
const InlineChunkHtmlPlugin = require('react-dev-utils/InlineChunkHtmlPlugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const { WebpackManifestPlugin } = require('webpack-manifest-plugin');
const InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
const WorkboxWebpackPlugin = require('workbox-webpack-plugin');
const ModuleScopePlugin = require('react-dev-utils/ModuleScopePlugin');
const getCSSModuleLocalIdent = require('react-dev-utils/getCSSModuleLocalIdent');
const paths = require('./paths');
const getClientEnvironment = require('./env');
const ModuleNotFoundPlugin = require('react-dev-utils/ModuleNotFoundPlugin');
const ForkTsCheckerWebpackPlugin = require('fork-ts-checker-webpack-plugin');
const MonacoWebpackPlugin = require('monaco-editor-webpack-plugin');
const ESLintPlugin = require('eslint-webpack-plugin');

// Source maps are resource heavy and can cause out of memory issue for large source files.
const shouldUseSourceMap = process.env.GENERATE_SOURCEMAP !== 'false';

const babelRuntimeEntry = require.resolve('babel-preset-react-app');
const babelRuntimeEntryHelpers = require.resolve(
  '@babel/runtime/helpers/esm/assertThisInitialized',
  { paths: [babelRuntimeEntry] }
);
const babelRuntimeRegenerator = require.resolve('@babel/runtime/regenerator', {
  paths: [babelRuntimeEntry]
});
// Some apps do not need the benefits of saving a web request, so not inlining the chunk
// makes for a smoother build process.
const shouldInlineRuntimeChunk = process.env.INLINE_RUNTIME_CHUNK !== 'false';

// Check if TypeScript is setup
const useTypeScript = fs.existsSync(paths.appTsConfig);

// style files regexes
const cssRegex = /\.css$/;
const cssModuleRegex = /\.module\.css$/;
const sassRegex = /\.(scss|sass)$/;
const sassModuleRegex = /\.module\.(scss|sass)$/;

const hasJsxRuntime = () => {
  if (process.env.DISABLE_NEW_JSX_TRANSFORM === 'true') {
    return false;
  }
};

// This is the production and development configuration.
// It is focused on developer experience, fast rebuilds, and a minimal bundle.
module.exports = function (webpackEnv) {
  const isEnvDevelopment = webpackEnv === 'development';
  const isEnvProduction = webpackEnv === 'production';

  // 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.
  // In development, we always serve from the root. This makes config easier.
  const publicPath = isEnvProduction
    ? paths.servedPath
    : isEnvDevelopment && '/';
  // Some apps do not use client-side routing with pushState.
  // For these, "homepage" can be set to "." to enable relative asset paths.
  const shouldUseRelativeAssetPaths = publicPath === './';

  // `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 = isEnvProduction
    ? publicPath.slice(0, -1)
    : isEnvDevelopment && '';
  // Get environment variables to inject into our app.
  const env = getClientEnvironment(publicUrl);

  // common function to get style loaders
  const getStyleLoaders = (cssOptions, preProcessor) => {
    const loaders = [
      isEnvDevelopment && require.resolve('style-loader'),
      isEnvProduction && {
        loader: MiniCssExtractPlugin.loader,
        options: Object.assign(
          {},
          shouldUseRelativeAssetPaths ? { publicPath: '../../' } : undefined
        )
      },
      {
        loader: require.resolve('css-loader'),
        options: cssOptions
      },
      {
        // Options for PostCSS as we reference these options twice
        // Adds vendor prefixing based on your specified browser support in
        // package.json
        loader: require.resolve('postcss-loader'),
        options: {
          // Necessary for external CSS imports to work
          // https://github.com/facebook/create-react-app/issues/2677
          implementation: require('postcss'),
          postcssOptions: {
            plugins: () => [
              require('postcss-flexbugs-fixes'),
              require('postcss-preset-env')({
                autoprefixer: {
                  flexbox: 'no-2009'
                },
                stage: 3
              })
            ]
          },
          sourceMap: isEnvProduction ? shouldUseSourceMap : isEnvDevelopment
        }
      }
    ].filter(Boolean);
    if (preProcessor) {
      loaders.push({
        loader: require.resolve(preProcessor),
        options: {
          sourceMap: isEnvProduction ? shouldUseSourceMap : isEnvDevelopment
        }
      });
    }
    return loaders;
  };

  return {
    mode: isEnvProduction ? 'production' : isEnvDevelopment && 'development',
    // Stop compilation early in production
    bail: isEnvProduction,
    devtool: isEnvProduction
      ? shouldUseSourceMap
        ? 'source-map'
        : false
      : isEnvDevelopment && 'eval-source-map',
    // These are the "entry points" to our application.
    // This means they will be the "root" imports that are included in JS bundle.
    entry: [
      // Include an alternative client for WebpackDevServer. A client's job is to
      // connect to WebpackDevServer by a socket and get notified about changes.
      // When you save a file, the client will either apply hot updates (in case
      // of CSS changes), or refresh the page (in case of JS changes). When you
      // make a syntax error, this client will display a syntax error overlay.
      // Note: instead of the default WebpackDevServer client, we use a custom one
      // to bring better experience for Create React App users. You can replace
      // the line below with these two lines if you prefer the stock client:
      // require.resolve('webpack-dev-server/client') + '?/',
      // require.resolve('webpack/hot/dev-server'),
      isEnvDevelopment &&
      require.resolve('react-dev-utils/webpackHotDevClient'),
      // Finally, this is your app's code:
      paths.appIndexJs
      // We include the app code last so that if there is a runtime error during
      // initialization, it doesn't blow up the WebpackDevServer client, and
      // changing JS code would still trigger a refresh.
    ].filter(Boolean),
    output: {
      // The build folder.
      path: isEnvProduction ? paths.appBuild : path.resolve(__dirname, 'dist'),
      // Add /* filename */ comments to generated require()s in the output.
      pathinfo: isEnvDevelopment,
      // There will be one main bundle, and one file per asynchronous chunk.
      // In development, it does not produce real files.
      filename: 'static/js/graph-explorer-v2.js',
      // We inferred the "public path" (such as / or /my-project) from homepage.
      // We use "/" in development.
      publicPath,
      // Point sourcemap entries to original disk location (format as URL on Windows)
      devtoolModuleFilenameTemplate: isEnvProduction
        ? info =>
          path
            .relative(paths.appSrc, info.absoluteResourcePath)
            .replace(/\\/g, '/')
        : isEnvDevelopment &&
        (info => path.resolve(info.absoluteResourcePath).replace(/\\/g, '/'))
    },
    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/facebook/create-react-app/issues/253
      modules: ['node_modules'].concat(
        // It is guaranteed to exist because we tweak it in `env.js`
        process.env.NODE_PATH.split(path.delimiter).filter(Boolean)
      ),
      // Some libraries import Node modules but don't use them in the browser.
      // Tell Webpack to provide false mocks for them so importing them works.
      fallback: {
        module: 'false',
        dgram: 'false',
        dns: 'mock',
        fs: 'false',
        net: 'false',
        tls: 'false',
        child_process: 'false'
      },
      // 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/facebook/create-react-app/issues/290
      // `web` extension prefixes have been added for better support
      // for React Native Web.
      extensions: paths.moduleFileExtensions
        .map(ext => `.${ext}`)
        .filter(ext => useTypeScript || !ext.includes('ts')),
      alias: {
        // Support React Native Web
        // https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
        'react-native': 'react-native-web'
      },
      plugins: [
        // Adds support for installing with Plug'n'Play, leading to faster installs and adding
        // guards against forgotten dependencies and such.
        // PnpWebpackPlugin,
        // Prevents users from importing files from outside of src/ (or node_modules/).
        // This often causes confusion because we only process files within src/ with babel.
        // To fix this, we prevent you from importing files out of src/ -- if you'd like to,
        // please link the files into your node_modules/ and let module-resolution kick in.
        // Make sure your source files are compiled, as they will not be processed in any way.
        new ModuleScopePlugin(paths.appSrc, [
          paths.appPackageJson,
          babelRuntimeEntry,
          babelRuntimeEntryHelpers,
          babelRuntimeRegenerator])
      ]
    },
    resolveLoader: {
      plugins: [
        // Also related to Plug'n'Play, but this time it tells Webpack to load its loaders
        // from the current package.
        // PnpWebpackPlugin.moduleLoader(module)
      ]
    },
    module: {
      strictExportPresence: true,
      rules: [
        // Disable require.ensure as it's not a standard language feature.
        {
          test: /\.[cm]?(js|tsx?)$/,
          parser: { requireEnsure: false }
        },
        {
          test: /\.m?js$/,
          exclude: /node_modules/,
          use: {
            loader: 'babel-loader',
            options: {
              presets: ['@babel/preset-env']
            }
          }
        },
        {
          // "oneOf" will traverse all following loaders until one will
          // match the requirements. When no loader matches it will fall
          // back to the "file" loader at the end of the loader list.
          oneOf: [
            // "url" loader works like "file" loader except that it embeds assets
            // smaller than specified limit in bytes as data URLs to avoid requests.
            // A missing `test` is equivalent to a match.
            {
              test: [/\.bmp$/, /\.gif$/, /\.jpe?g$/, /\.png$/],
              loader: require.resolve('url-loader'),
              options: {
                limit: 10000,
                name: 'static/media/[name].[contenthash:8].[ext]'
              }
            },
            // Process application JS with Babel.
            // The preset includes JSX, Flow, TypeScript, and some ESnext features.
            {
              test: /\.(js|mjs|jsx|ts|tsx)$/,
              include: paths.appSrc,
              loader: require.resolve('babel-loader'),
              options: {
                customize: require.resolve(
                  'babel-preset-react-app/webpack-overrides'
                ),
                presets: [
                  [
                    require.resolve('babel-preset-react-app'),
                    {
                      runtime: hasJsxRuntime ? 'automatic' : 'classic'
                    }
                  ]
                ],
                // This is a feature of `babel-loader` for webpack (not Babel itself).
                // It enables caching results in ./node_modules/.cache/babel-loader/
                // directory for faster rebuilds.
                cacheDirectory: true,
                cacheCompression: false,
                compact: isEnvProduction
              }
            },
            // Process any JS outside of the app with Babel.
            // Unlike the application JS, we only compile the standard ES features.
            {
              test: /\.(js|mjs)$/,
              exclude: /@babel(?:\/|\\{1,2})runtime/,
              loader: require.resolve('babel-loader'),
              options: {
                babelrc: false,
                configFile: false,
                compact: false,
                presets: [
                  [
                    require.resolve('babel-preset-react-app/dependencies'),
                    { helpers: true }
                  ]
                ],
                cacheDirectory: true,
                cacheCompression: false,

                // If an error happens in a package, it's possible to be
                // because it was compiled. Thus, we don't want the browser
                // debugger to show the original code. Instead, the code
                // being evaluated would be much more helpful.
                sourceMaps: false
              }
            },
            // "postcss" loader applies autoprefixer to our CSS.
            // "css" loader resolves paths in CSS and adds assets as dependencies.
            // "style" loader turns CSS into JS modules that inject <style> tags.
            // In production, we use MiniCSSExtractPlugin to extract that CSS
            // to a file, but in development "style" loader enables hot editing
            // of CSS.
            // By default we support CSS Modules with the extension .module.css
            {
              test: cssRegex,
              exclude: cssModuleRegex,
              use: getStyleLoaders({
                importLoaders: 1,
                sourceMap: isEnvProduction
                  ? shouldUseSourceMap
                  : isEnvDevelopment
              }),
              // Don't consider CSS imports dead code even if the
              // containing package claims to have no side effects.
              // Remove this when webpack adds a warning or an error for this.
              // See https://github.com/webpack/webpack/issues/6571
              sideEffects: true
            },
            // Adds support for CSS Modules (https://github.com/css-modules/css-modules)
            // using the extension .module.css
            {
              test: cssModuleRegex,
              use: getStyleLoaders({
                importLoaders: 1,
                sourceMap: isEnvProduction
                  ? shouldUseSourceMap
                  : isEnvDevelopment,
                modules: true,
                getLocalIdent: getCSSModuleLocalIdent
              })
            },
            // Opt-in support for SASS (using .scss or .sass extensions).
            // By default we support SASS Modules with the
            // extensions .module.scss or .module.sass
            {
              test: sassRegex,
              exclude: sassModuleRegex,
              use: getStyleLoaders(
                {
                  importLoaders: 2,
                  sourceMap: isEnvProduction
                    ? shouldUseSourceMap
                    : isEnvDevelopment
                },
                'sass-loader'
              ),
              // Don't consider CSS imports dead code even if the
              // containing package claims to have no side effects.
              // Remove this when webpack adds a warning or an error for this.
              // See https://github.com/webpack/webpack/issues/6571
              sideEffects: true
            },
            // Adds support for CSS Modules, but using SASS
            // using the extension .module.scss or .module.sass
            {
              test: sassModuleRegex,
              use: getStyleLoaders(
                {
                  importLoaders: 2,
                  sourceMap: isEnvProduction
                    ? shouldUseSourceMap
                    : isEnvDevelopment,
                  modules: true,
                  getLocalIdent: getCSSModuleLocalIdent
                },
                'sass-loader'
              )
            },
            {
              test: /\.css$/,
              use: ['style-loader', 'css-loader']
            },
            {
              test: /\.ttf$/,
              type: 'asset/resource'
            },
            // "file" loader makes sure those assets get served by WebpackDevServer.
            // When you `import` an asset, you get its (virtual) filename.
            // In production, they would get copied to the `build` folder.
            // This loader doesn't use a "test" so it will catch all modules
            // that fall through the other loaders.
            {
              // Exclude `js` files to keep "css" loader working as it injects
              // its runtime that would otherwise be processed through "file" loader.
              // Also exclude `html` and `json` extensions so they get processed
              // by webpacks internal loaders.
              exclude: [/\.(js|mjs|jsx|ts|tsx)$/, /\.html$/, /\.json$/, /data:image\/svg\+xml;/],
              type: 'asset/resource'
            }
            // ** STOP ** Are you adding a new loader?
            // Make sure to add the new loader(s) before the "file" loader.
          ]
        }
      ]
    },
    plugins: [
      new webpack.optimize.LimitChunkCountPlugin({
        maxChunks: 1
      }),
      new MonacoWebpackPlugin({
        languages: [
          'json',
          'typescript',
          'javascript',
          'css',
          'java',
          'csharp',
          'html',
          'powershell',
          'go',
          'php',
          'python',
          'bash'
        ]
      }),
      // Generates an `index.html` file with the <script> injected.
      new HtmlWebpackPlugin(
        Object.assign(
          {},
          {
            inject: true,
            template: paths.appHtml
          },
          isEnvProduction
            ? {
              minify: {
                removeComments: true,
                collapseWhitespace: false,
                removeRedundantAttributes: true,
                useShortDoctype: true,
                removeEmptyAttributes: true,
                removeStyleLinkTypeAttributes: true,
                keepClosingSlash: true,
                minifyJS: false,
                minifyCSS: true,
                minifyURLs: true
              }
            }
            : undefined
        )
      ),
      new ESLintPlugin({
        formatter: require.resolve('react-dev-utils/eslintFormatter'),
        eslintPath: require.resolve('eslint')
      }),
      // Inlines the webpack runtime script. This script is too small to warrant
      // a network request.
      isEnvProduction &&
      shouldInlineRuntimeChunk &&
      new InlineChunkHtmlPlugin(HtmlWebpackPlugin, [/runtime~.+[.]js/]),
      // 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.
      // In development, this will be an empty string.
      new InterpolateHtmlPlugin(HtmlWebpackPlugin, env.raw),
      // This gives some necessary context to module not found errors, such as
      // the requesting resource.
      new ModuleNotFoundPlugin(paths.appPath),
      // 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 is set to production
      // during a production build.
      // Otherwise React will be compiled in the very slow development mode.
      new webpack.DefinePlugin(env.stringified),
      // This is necessary to emit hot updates (currently CSS only):
      // isEnvDevelopment && new webpack.HotModuleReplacementPlugin(),
      // Watcher doesn't work well if you mistype casing in a path so we use
      // a plugin that prints an error when you attempt to do this.
      // See https://github.com/facebook/create-react-app/issues/240
      isEnvDevelopment && new CaseSensitivePathsPlugin(),
      // If you require a missing module and then `npm install` it, you still have
      // to restart the development server for Webpack to discover it. This plugin
      // makes the discovery automatic so you don't have to restart.
      // See https://github.com/facebook/create-react-app/issues/186
      // isEnvDevelopment &&
      // new WatchMissingNodeModulesPlugin(paths.appNodeModules),
      isEnvProduction &&
      new MiniCssExtractPlugin({
        filename: 'static/css/graph-explorer-v2.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 WebpackManifestPlugin({
        fileName: 'asset-manifest.json',
        publicPath
      }),
      // 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({
        resourceRegExp: /^\.\/locale$/,
        contextRegExp: /moment$/
      }),
      // Generate a service worker script that will precache, and keep up to date,
      // the HTML & assets that are part of the Webpack build.
      isEnvProduction &&
      new WorkboxWebpackPlugin.GenerateSW({
        clientsClaim: true,
        exclude: [/\.map$/, /asset-manifest\.json$/],
        navigateFallback: publicUrl + '/index.html',
        navigateFallbackDenylist: [
          // Exclude URLs starting with /_, as they're likely an API call
          new RegExp('^/_'),
          // Exclude URLs containing a dot, as they're likely a resource in
          // public/ and not a SPA route
          new RegExp('/[^/]+\\.[^/]+$')
        ],
        maximumFileSizeToCacheInBytes: 10 * 1024 * 1024
      }),
      // TypeScript type checking
      useTypeScript &&
      new ForkTsCheckerWebpackPlugin()
    ].filter(Boolean),
    // Turn off performance processing because we utilize
    // our own hints via the FileSizeReporter
    performance: false
  };
};