webpack.prod.config.js

const path = require("path");
const HtmlWebPackPlugin = require("html-webpack-plugin");
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
const UglifyJsPlugin = require("uglifyjs-webpack-plugin");
const OptimizeCSSAssetsPlugin = require("optimize-css-assets-webpack-plugin");

module.exports = {
  entry: {
    main: "./src/index.js",
  },
  output: {
    path: path.join(__dirname, "dist"),
    publicPath: "/",
    filename: "[name].js",
  },
  target: "web",
  devtool: "source-map",
  // Webpack 4 does not have a CSS minifier, although
  // Webpack 5 will likely come with one
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        cache: true,
        parallel: true,
        sourceMap: true, // set to true if you want JS source maps
      }),
      new OptimizeCSSAssetsPlugin({}),
    ],
  },
  module: {
    rules: [
      {
        // Transpiles ES6-8 into ES5
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader",
        },
      },
      {
        // Loads the javacript into html template provided.
        // Entry point is set below in HtmlWebPackPlugin in Plugins
        test: /\.html$/,
        use: [
          {
            loader: "html-loader",
            options: { minimize: true },
          },
        ],
      },
      {
        // Loads images into CSS and Javascript files
        test: /\.jpg$/,
        type: "asset/resource",
      },
      {
        // Loads CSS into a file when you import it via Javascript
        // Rules are set in MiniCssExtractPlugin
        test: /\.css$/,
        use: [MiniCssExtractPlugin.loader, "css-loader"],
      },
    ],
  },
  plugins: [
    new HtmlWebPackPlugin({
      template: "./src/html/index.html",
      filename: "./index.html",
    }),
    new MiniCssExtractPlugin({
      filename: "[name].css",
      chunkFilename: "[id].css",
    }),
  ],
};