How to use react-scripts - 10 common examples

throw err;
});

// Ensure environment variables are read.
require("react-scripts/config/env");

const fs = require("fs-extra");
const chalk = require("react-dev-utils/chalk");
const webpack = require("webpack");
const checkRequiredFiles = require("react-dev-utils/checkRequiredFiles");
const formatWebpackMessages = require("react-dev-utils/formatWebpackMessages");
const paths = require("react-scripts/config/paths");
const configFactory = require("react-scripts/config/webpack.config");

// Warn and crash if required files are missing
if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
  process.exit(1);
}

const configDevelopment = configFactory("development");
const configProduction = configFactory("production");
const config = configDevelopment;
config.entry = configProduction.entry;
config.output.path = configProduction.output.path;
config.plugins = config.plugins.filter(
  p => p.constructor.name !== "HotModuleReplacementPlugin"
);

fs.emptyDirSync(paths.appBuild);
const compiler = webpack(config);
compiler.watch({ ignored: [paths.appNodeModules] }, (err, stats) => {
  let messages;

const extractTextPluginOptions = shouldUseRelativeAssetPaths
  ? // Making sure that the publicPath goes back to to build folder.
    { publicPath: Array(cssFilename.split('/').length).join('../') }
  : {};

// 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 = {
  // 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,
  // In production, we only want to load the polyfills and the app code.
  entry: [require.resolve('react-scripts/config/polyfills'), 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, '/'),
  },

// Warn and crash if required files are missing
if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
  process.exit(1);
}

const configDevelopment = configFactory("development");
const configProduction = configFactory("production");
const config = configDevelopment;
config.entry = configProduction.entry;
config.output.path = configProduction.output.path;
config.plugins = config.plugins.filter(
  p => p.constructor.name !== "HotModuleReplacementPlugin"
);

fs.emptyDirSync(paths.appBuild);
const compiler = webpack(config);
compiler.watch({ ignored: [paths.appNodeModules] }, (err, stats) => {
  let messages;
  if (err) {
    let errMessage = err.message;

    messages = formatWebpackMessages({
      errors: [errMessage],
      warnings: []
    });
  } else {
    messages = formatWebpackMessages(
      stats.toJson({ all: false, warnings: true, errors: true })
    );
  }
  if (messages.errors.length) {

const paths = require('react-scripts/config/paths');
const ExtractTextPlugin = require('extract-text-webpack-plugin');
const baseConfig = require('./overrides-config.base');

// 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;
// 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 === './';
const cssFilename = 'static/css/[name].[contenthash:8].css';
const extractTextPluginOptions = shouldUseRelativeAssetPaths
  ? // Making sure that the publicPath goes back to to build folder.
    { publicPath: Array(cssFilename.split('/').length).join('../') }
  : {};

module.exports = function(config) {
  // Define the root path alias
  let alias = config.resolve.alias;
  alias["@"] = baseConfig.rootPath;

  // Use your ESLint 
  /*let eslintLoader = config.module.rules[0];

process.env.NODE_ENV = "production";
process.env.BABEL_ENV = "production";

require("react-scripts/config/env");

const fs = require("fs-extra");
const path = require("path");
const paths = require("react-scripts/config/paths");

paths.appBuild = path.join(__dirname, "../ui_build");
paths.servedPath = "./";

const webpack = require("webpack");
const config = require("react-scripts/config/webpack.config.js")("production");

// removes react-dev-utils/webpackHotDevClient.js at first in the array
// config.entry.shift();

const webpackConfigured = webpack(config);

function callback(err, stats) {
  if (err) {
    // eslint-disable-next-line no-console
    console.error(err);
  } else {
    copyPublicFolder();
  }

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, '/'),
  },
  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.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: ['.web.js', '.js', '.json', '.web.jsx', '.jsx'],
    alias: {
      // @remove-on-eject-begin
      // Resolve Babel runtime relative to react-scripts.
      // It usually still works on npm 3 without this but it would be
      // unfortunate to rely on, as react-scripts could be symlinked,
      // and thus babel-runtime might not be resolvable from the source.

if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
  process.exit(1);
}

const configDevelopment = configFactory("development");
const configProduction = configFactory("production");
const config = configDevelopment;
config.entry = configProduction.entry;
config.output.path = configProduction.output.path;
config.plugins = config.plugins.filter(
  p => p.constructor.name !== "HotModuleReplacementPlugin"
);

fs.emptyDirSync(paths.appBuild);
const compiler = webpack(config);
compiler.watch({ ignored: [paths.appNodeModules] }, (err, stats) => {
  let messages;
  if (err) {
    let errMessage = err.message;

    messages = formatWebpackMessages({
      errors: [errMessage],
      warnings: []
    });
  } else {
    messages = formatWebpackMessages(
      stats.toJson({ all: false, warnings: true, errors: true })
    );
  }
  if (messages.errors.length) {
    // Only keep the first error. Others are often indicative
    // of the same problem, but confuse the reader with noise.

const fs = require("fs-extra");
const chalk = require("react-dev-utils/chalk");
const webpack = require("webpack");
const checkRequiredFiles = require("react-dev-utils/checkRequiredFiles");
const formatWebpackMessages = require("react-dev-utils/formatWebpackMessages");
const paths = require("react-scripts/config/paths");
const configFactory = require("react-scripts/config/webpack.config");

// Warn and crash if required files are missing
if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
  process.exit(1);
}

const configDevelopment = configFactory("development");
const configProduction = configFactory("production");
const config = configDevelopment;
config.entry = configProduction.entry;
config.output.path = configProduction.output.path;
config.plugins = config.plugins.filter(
  p => p.constructor.name !== "HotModuleReplacementPlugin"
);

fs.emptyDirSync(paths.appBuild);
const compiler = webpack(config);
compiler.watch({ ignored: [paths.appNodeModules] }, (err, stats) => {
  let messages;
  if (err) {
    let errMessage = err.message;

    messages = formatWebpackMessages({
      errors: [errMessage],

require("react-scripts/config/env");

const fs = require("fs-extra");
const chalk = require("react-dev-utils/chalk");
const webpack = require("webpack");
const checkRequiredFiles = require("react-dev-utils/checkRequiredFiles");
const formatWebpackMessages = require("react-dev-utils/formatWebpackMessages");
const paths = require("react-scripts/config/paths");
const configFactory = require("react-scripts/config/webpack.config");

// Warn and crash if required files are missing
if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
  process.exit(1);
}

const configDevelopment = configFactory("development");
const configProduction = configFactory("production");
const config = configDevelopment;
config.entry = configProduction.entry;
config.output.path = configProduction.output.path;
config.plugins = config.plugins.filter(
  p => p.constructor.name !== "HotModuleReplacementPlugin"
);

fs.emptyDirSync(paths.appBuild);
const compiler = webpack(config);
compiler.watch({ ignored: [paths.appNodeModules] }, (err, stats) => {
  let messages;
  if (err) {
    let errMessage = err.message;

    messages = formatWebpackMessages({

const path = require( 'path' );

// webpack.config.prod.js checks this.
process.env.NODE_ENV = 'production';

// Load the create-react-app config.
const webpackConfigProd = require( 'react-scripts/config/webpack.config.prod' );

// Modify the config according to our needs.

const babelLoader = webpackConfigProd.module.loaders
	.find( loader => loader.loader === 'babel' );

if ( ! babelLoader ) {
	console.error( webpackConfigProd.module.loaders );
	throw new Error( 'Couldn\'t find the babel loader config.' );
}

babelLoader.query.plugins = ( babelLoader.query.plugins || [] )
	.filter( pluginName => pluginName !== 'lodash' )
	.concat( 'lodash' );

console.log( 'Added lodash babel plugin to build' );

if ( process.env.WPCOM_BUILD ) {
	babelLoader.query.plugins.push( path.resolve(
		__dirname, '..', 'src', 'lib', 'babel-replace-config-import.js'
	) );
	console.log( 'Added config override for WP.com build' );
}