webpack.config.js

const HtmlWebpackPlugin = require('html-webpack-plugin');
const Dotenv = require('dotenv-webpack');
const path = require('path');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const UglifyJsPlugin = require('uglifyjs-webpack-plugin');

module.exports = {
    module: {
        rules: [
            {
                test: /\.css$/,
                use: ['style-loader', 'css-loader'],
            },
            {
                test: /\.scss$/,
                use: ['style-loader', 'css-loader', 'sass-loader'],
            },
            {
                test: /\.js$/,
                exclude: /node_modules/,
                use: ['babel-loader'],
            },
            {
                test: /\.(png|jpe?g|gif)$/i,
                loader: 'file-loader',
                options: {
                    name(resourcePath, resourceQuery) {
                        return '[contenthash].[ext]';
                    },
                },
            },
        ],
    },
    resolve: {
        modules: [path.join(__dirname), 'node_modules'],
    },
    plugins: [
        new HtmlWebpackPlugin({
            template: path.resolve(__dirname, '', 'template.html'),
        }),
        new Dotenv(),
    ],
    devServer: {
        compress: true,
        port: 3000,
        historyApiFallback: true,
    },
    output: {
        filename: 'js/[name].[chunkhash:8].js',
        chunkFilename: 'js/[name].[chunkhash:8].chunk.js',
        publicPath: '/',
    },
    optimization: {
        splitChunks: {
            chunks: 'async',
            minSize: 20000,
            minRemainingSize: 0,
            minChunks: 2,
            maxAsyncRequests: 30,
            maxInitialRequests: 30,
            enforceSizeThreshold: 50000,
            cacheGroups: {
                defaultVendors: {
                    test: /[\\/]node_modules[\\/]/,
                    priority: -10,
                    reuseExistingChunk: true,
                },
                default: {
                    minChunks: 2,
                    priority: -20,
                    reuseExistingChunk: true,
                },
            },
        },
        minimizer: [
            new UglifyJsPlugin({
                cache: true,
                parallel: true,
                sourceMap: false, // set to true if you want JS source maps
            }),
            new OptimizeCSSAssetsPlugin({}),
        ],
    },
};