webpack.config.js

const path = require('path');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const { DefinePlugin } = require('webpack');

const config = {
  entry: {
    app: './src/index.js',
  },
  output: {
    path: path.resolve(__dirname, 'dist'),
    filename: '[name].js',
  },
  externals: {
    '@wordpress/api-fetch': ['wp', 'apiFetch'],
    '@wordpress/i18n': ['wp', 'i18n'],
  },
  module: {
    rules: [
      {
        test: /\.(js|jsx)$/,
        use: 'babel-loader',
        exclude: /node_modules/,
      },
      {
        test: /\.css$/,
        use: [
          MiniCssExtractPlugin.loader,
          {
            loader: 'css-loader',
            options: {
              importLoaders: 1,
            },
          },
          'postcss-loader',
        ],
      },
      {
        test: /\.scss$/,
        use: [MiniCssExtractPlugin.loader, 'css-loader', 'sass-loader'],
      },
      {
        test: /\.svg$/,
        use: 'file-loader',
      },
      {
        test: /\.png$/,
        use: [
          {
            loader: 'url-loader',
            options: {
              mimetype: 'image/png',
            },
          },
        ],
      },
    ],
  },
  resolve: {
    extensions: ['.js', '.jsx'],
    alias: {
      'react-dom': '@hot-loader/react-dom',
    },
    fallback: {
      "path": require.resolve("path-browserify")
    },
  },
  devServer: {
    contentBase: './dist',
    headers: {
      'Access-Control-Allow-Origin': '*',
      'Access-Control-Allow-Methods': 'GET, POST, PUT, DELETE, PATCH, OPTIONS',
      'Access-Control-Allow-Headers':
        'X-Requested-With, content-type, Authorization',
    },
  },
  optimization: {
    runtimeChunk: 'single',
    splitChunks: {
      cacheGroups: {
        vendor: {
          test: /[\\/]node_modules[\\/]/,
          name: 'vendors',
          chunks: 'all',
        },
      },
    },
  },
  plugins: [
    new MiniCssExtractPlugin(),
    new DefinePlugin({
      'process.env.FORCE_REDUCED_MOTION': JSON.stringify(
        process.env.FORCE_REDUCED_MOTION
      ),
    }),
  ],
};

module.exports = (env, argv) => {
  if (argv.hot) {
    // Cannot use 'contenthash' when hot reloading is enabled.
    config.output.filename = '[name].[hash].js';
  }

  return config;
};