@expo/webpack-config
    TypeScript icon, indicating that this package has built-in type declarations

    0.16.24 • Public • Published

    👋 Welcome to
    @expo/webpack-config

    Webpack config that's optimized for running universal React and react-native-web projects

    Circle CI


    Documentation

    To learn more about how to use this Webpack config, check out the docs here: Customizing the Webpack config

    Contributing to the docs

    API

    Running expo customize:web will generate this default config in your project.

    const createExpoWebpackConfigAsync = require('@expo/webpack-config');
    
    module.exports = async function (env, argv) {
      const config = await createExpoWebpackConfigAsync(env, argv);
      // Customize the config before returning it.
      return config;
    };

    Types

    Environment

    The main options used to configure how @expo/webpack-config works.

    name type default description
    projectRoot string required Root of the Expo project.
    https boolean false Should the dev server use https protocol.
    mode Mode required The Webpack mode to bundle the project in.
    platform ExpoPlatform required The target platform to bundle for.
    pwa boolean true Generate the PWA image assets in production mode.
    babel ExpoBabelOptions undefined Control how the default Babel loader is configured.

    Environment internal

    name type default description
    config ExpoConfig undefined The Expo project config, this should be read using @expo/config.
    locations FilePaths undefined Paths used to locate where things are.

    ExpoPlatform

    | type | description | | ------ | ----------- | ----- | ----------- | ---------------------------------------------------------------------------------------------------------- | | 'ios' | 'android' | 'web' | 'electron' | The target platform to bundle for. Native platforms are experimental and require a special native runtime. |

    ExpoBabelOptions

    Control how the default Babel loader is configured.

    name type default description
    dangerouslyAddModulePathsToTranspile string[] undefined Add the names of node_modules that should be included transpilation step.

    Guides

    PWAs

    • See the docs for expo-pwa to learn more about creating the assets manually.
    • Disable automatic PWA generation with expo build:web --no-pwa.
    • expo build:web will automatically skip any PWA asset that's already linked in the project's local web/index.html.
    • Having sharp CLI installed globally will speed up asset generation, if it's not installed, Jimp will be used instead.

    Chrome PWAs

    Manifest.json

    The manifest.json will be created using the values in the project's app.config.js:

    Generating the manifest.json will be skipped if the following exists in the project's web/index.html:

    Show HTML
    <link rel="manifest" href="..." />

    If the icons array is defined in your manifest.json, then Chrome PWA icon generation will be skipped.

    Chrome PWA Icons

    Icons will be generated using the file defined in your app.config.js under android.icon and it'll fallback to icon.

    Show manifest.json
    {
      "icons": [
        {
          "src": "...",
          "sizes": "144x144",
          "type": "image/png"
        },
        {
          "src": "...",
          "sizes": "192x192",
          "type": "image/png"
        },
        {
          "src": "...",
          "sizes": "512x512",
          "type": "image/png"
        }
      ]
    }

    Favicons

    Favicons will be generated using the file defined in your app.config.js under web.favicon and it'll fallback to icon.

    Asset generation for Favicons will be individually skipped if any of the following fields exist in your web/index.html:

    Show HTML
    <link rel="icon" type="image/png" sizes="16x16" href="..." />
    <link rel="icon" type="image/png" sizes="32x32" href="..." />
    <link rel="shortcut icon" href="..." />

    Safari PWAs

    Icons will be generated using the file defined in your app.config.js under ios.icon and it'll fallback to icon. The splash screens look at ios.splash and fallback to splash.

    Asset generation for Safari PWA icons/splash screens will be individually skipped if any of the following fields exist in your web/index.html:

    Icons
    Show HTML
    <link rel="apple-touch-icon" sizes="180x180" href="..." />
    Splash Screens
    Show HTML
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 320px) and (device-height: 568px) and (-webkit-device-pixel-ratio: 2) and (orientation: landscape)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 320px) and (device-height: 568px) and (-webkit-device-pixel-ratio: 2) and (orientation: portrait)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 414px) and (device-height: 896px) and (-webkit-device-pixel-ratio: 3) and (orientation: landscape)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 414px) and (device-height: 896px) and (-webkit-device-pixel-ratio: 3) and (orientation: portrait)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 414px) and (device-height: 896px) and (-webkit-device-pixel-ratio: 2) and (orientation: landscape)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 414px) and (device-height: 896px) and (-webkit-device-pixel-ratio: 2) and (orientation: portrait)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 375px) and (device-height: 812px) and (-webkit-device-pixel-ratio: 3) and (orientation: landscape)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 375px) and (device-height: 812px) and (-webkit-device-pixel-ratio: 3) and (orientation: portrait)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 414px) and (device-height: 736px) and (-webkit-device-pixel-ratio: 3) and (orientation: landscape)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 414px) and (device-height: 736px) and (-webkit-device-pixel-ratio: 3) and (orientation: portrait)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 375px) and (device-height: 667px) and (-webkit-device-pixel-ratio: 2) and (orientation: landscape)"
      href="..."
    />
    <link
      rel="apple-touch-startup-image"
      media="screen and (device-width: 375px) and (device-height: 667px) and (-webkit-device-pixel-ratio: 2) and (orientation: portrait)"
      href="..."
    />

    Include modules

    You may find that you want to include universal modules that aren't part of the default modules. You can do this by customizing the Webpack config:

    const createExpoWebpackConfigAsync = require('@expo/webpack-config');
    
    module.exports = async function (env, argv) {
      const config = await createExpoWebpackConfigAsync(
        {
          ...env,
          babel: {
            dangerouslyAddModulePathsToTranspile: [
              // Ensure that all packages starting with @evanbacon are transpiled.
              '@evanbacon',
            ],
          },
        },
        argv
      );
      return config;
    };

    withUnimodules

    If you're adding support to some other Webpack config like in Storybook or Gatsby you can use the same process to include custom modules:

    const { withUnimodules } = require('@expo/webpack-config/addons');
    
    module.exports = function () {
      const someWebpackConfig = {
        /* Your custom Webpack config */
      };
    
      // Add Expo support...
      const configWithExpo = withUnimodules(someWebpackConfig, {
        projectRoot: __dirname,
        babel: {
          dangerouslyAddModulePathsToTranspile: [
            // Ensure that all packages starting with @evanbacon are transpiled.
            '@evanbacon',
          ],
        },
      });
    
      return configWithExpo;
    };

    This method should be used instead of using the expo.web.build.babel.include field of the app.json.

    Modify the babel loader

    If you want to modify the babel loader further, you can retrieve it using the helper method getExpoBabelLoader like this:

    const createExpoWebpackConfigAsync = require('@expo/webpack-config');
    const { getExpoBabelLoader } = require('@expo/webpack-config/utils');
    
    module.exports = async function (env, argv) {
      const config = await createExpoWebpackConfigAsync(env, argv);
      const loader = getExpoBabelLoader(config);
      if (loader) {
        // Modify the loader...
      }
      return config;
    };

    Service workers

    Example of using service workers with Expo: npx create-react-native-app -t with-workbox

    This webpack config currently does not supply service workers by default, they can be added to the project locally: Adding Service Workers.

    Environment Variables

    • EXPO_WEBPACK_DEFINE_ENVIRONMENT_AS_KEYS: Should the define plugin explicitly set environment variables like process.env.FOO instead of creating an object like proces.env: { FOO }. Defaults to false. Next.js uses this to prevent overwriting injected environment variables.
    • IMAGE_INLINE_SIZE_LIMIT: By default, images smaller than 10,000 bytes are encoded as a data URI in base64 and inlined in the CSS or JS build artifact. Set this to control the size limit in bytes. Setting it to 0 will disable the inlining of images. This is only used in production.

    Exports

    addons

    For adding features to an existing Webpack config.

    withUnimodules

    import { withUnimodules } from '@expo/webpack-config/addons';

    Wrap your existing webpack config with support for Unimodules (Expo web). ex: Storybook ({ config }) => withUnimodules(config)

    params

    • webpackConfig: AnyConfiguration = {} Optional existing Webpack config to modify.
    • env: InputEnvironment = {} Optional [Environment][#environment] options for configuring what features the Webpack config supports.
    • argv: Arguments = {}

    withOptimizations

    import { withOptimizations } from '@expo/webpack-config/addons';

    withAlias

    Apply aliases to a Webpack config.

    import { withAlias } from '@expo/webpack-config/addons';

    withDevServer

    import { withDevServer } from '@expo/webpack-config/addons';

    withNodeMocks

    import { withNodeMocks } from '@expo/webpack-config/addons';

    withEntry

    import { withEntry } from '@expo/webpack-config/addons';

    withTypeScriptAsync

    import { withTypeScriptAsync } from '@expo/webpack-config/addons';

    env

    Getting the config, paths, mode, and various other settings in your environment.

    getConfig

    import { getConfig } from '@expo/webpack-config/env';

    getMode

    import { getMode } from '@expo/webpack-config/env';

    validateEnvironment

    import { validateEnvironment } from '@expo/webpack-config/env';

    getAliases

    import { getAliases } from '@expo/webpack-config/env';

    getPaths

    import { getPaths } from '@expo/webpack-config/env';

    getPathsAsync

    import { getPathsAsync } from '@expo/webpack-config/env';

    getServedPath

    import { getServedPath } from '@expo/webpack-config/env';

    getPublicPaths

    import { getPublicPaths } from '@expo/webpack-config/env';

    getProductionPath

    import { getProductionPath } from '@expo/webpack-config/env';

    getAbsolute

    import { getAbsolute } from '@expo/webpack-config/env';

    getModuleFileExtensions

    import { getModuleFileExtensions } from '@expo/webpack-config/env';

    loaders

    The module rules used to load various files.

    imageLoaderRule

    import { imageLoaderRule } from '@expo/webpack-config/loaders';

    This is needed for webpack to import static images in JavaScript files. "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.

    fallbackLoaderRule

    import { fallbackLoaderRule } from '@expo/webpack-config/loaders';

    "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.

    styleLoaderRule

    import { styleLoaderRule } from '@expo/webpack-config/loaders';

    Default CSS loader.

    plugins

    import /* */ '@expo/webpack-config/plugins';

    Custom versions of Webpack Plugins that are optimized for use with native React runtimes.

    ExpoDefinePlugin

    import { ExpoDefinePlugin } from '@expo/webpack-config/plugins';

    Required for expo-constants https://docs.expo.dev/versions/latest/sdk/constants/. This surfaces the app.json (config) as an environment variable which is then parsed by expo-constants.

    ExpoHtmlWebpackPlugin

    import { ExpoHtmlWebpackPlugin } from '@expo/webpack-config/plugins';

    Generates an index.html file with the <script> injected.

    ExpoInterpolateHtmlPlugin

    import { ExpoInterpolateHtmlPlugin } from '@expo/webpack-config/plugins';

    Add variables to the index.html.

    utils

    Tools for resolving fields, or searching and indexing loaders and plugins.

    resolveEntryAsync

    import { resolveEntryAsync } from '@expo/webpack-config/utils';

    What it does not do

    • Gzip compression: This was supported in beta but later removed in favor of hosting providers like Now and Netlify automatically compressing files in the server.

    License

    The Expo source code is made available under the MIT license. Some of the dependencies are licensed differently, with the BSD license, for example.


    License: MIT

    Keywords

    none

    Install

    npm i @expo/webpack-config

    DownloadsWeekly Downloads

    124,436

    Version

    0.16.24

    License

    MIT

    Unpacked Size

    509 kB

    Total Files

    176

    Last publish

    Collaborators

    • tsapeta
    • dsokal
    • wkozyra
    • bbarthec
    • ide
    • lukmccall
    • kbrandwijk
    • kgc00
    • fiber-god
    • brentvatne
    • ccheever
    • evanbacon
    • quinlanj
    • esamelson
    • expoadmin
    • tcdavis
    • exponent
    • wschurman
    • bycedric
    • jonsamp
    • princefleaswallow
    • andyboythekid
    • kudochien