webpack.config.js

const path = require('path');
const HTMLWebpackPlugin = require('html-webpack-plugin');
const {CleanWebpackPlugin} = require('clean-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const OptimizeCssAssetWebpackPlugin = require('optimize-css-assets-webpack-plugin');
const TerserWebpackPlugin = require('terser-webpack-plugin');
const ImageMinimizerPlugin = require('image-minimizer-webpack-plugin');

const isDev = process.env.NODE_ENV === 'development';
const isProd = !isDev;

const filename = (ext) => isDev ? `[name].${ext}` : `[name].[contenthash].${ext}`;

const optimization = () => {
  const configObj = {
    splitChunks: {
      chunks: 'all'
    }
  };

  if(isProd) {
    configObj.minimizer = [
      new OptimizeCssAssetWebpackPlugin(),
      new TerserWebpackPlugin()
    ];
  }
  return configObj;
};

const plugins = () => {
  const basePlugins = [
    new HTMLWebpackPlugin(
      {
      template: path.resolve(__dirname, 'src/index.html'),
      filename: 'index.html',
      inject: 'body',
      minify: {
        collapseWhitespace: isProd
      }
    }
    ),
    new CleanWebpackPlugin(),
    new MiniCssExtractPlugin({
      filename: `./css/${filename('css')}`
    })
  ];

  if(isProd) {
    basePlugins.push(
      new ImageMinimizerPlugin({
        minimizerOptions: {

          plugins: [
            ['gifsicle', { interlaced: true }],
            ['jpegtran', { progressive: true }],
            ['optipng', { optimizationLevel: 5 }],
            [
              'svgo',
              {
                plugins: [
                  {
                    removeViewBox: false,
                  },
                ],
              },
            ],
          ],
        },
      }),
    );
  }

  return basePlugins;
};

module.exports = {
  context: path.resolve(__dirname, 'src'),
  mode: 'development',
  entry: './js/script.js',
  output: {
    filename: `./js/${filename('js')}`,
    path: path.resolve(__dirname, 'dist'),
  },
  devServer: {
    historyApiFallback: true,
    contentBase: path.resolve(__dirname, 'dist'),
    open: true,
    compress: true,
    hot: true,
    port: 8080,
  },
  optimization: optimization(),
  plugins: plugins(),
  devtool: isProd ? false : 'source-map',
  module: {
    rules: [{
        test: /\.css$/i,
        use: [{
            loader: MiniCssExtractPlugin.loader,
            options: {
              hmr: isDev
            },
          },
          'css-loader'
        ],
      },
      {
        test: /\.s[ac]ss$/,
        use: [{
            loader: MiniCssExtractPlugin.loader,
            options: {
              publicPath: (resourcePath, context) => {
                return path.relative(path.dirname(resourcePath), context) + '/';
              },
            }
          },
          'css-loader',
          'sass-loader'
        ]
      },
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: ['babel-loader']
      },
      {
        test: /\.(gif|png|jpg|jpeg|svg|webp)$/,
        use: [
          `file-loader?name=./img/${filename('[ext]')}`,
          {
            loader: 'image-webpack-loader',
            options: {}
          },
        ]
      },
      {
        test: /\.(woff2|ttf)$/,
        use: [{
          loader: 'file-loader',
          options: {
            name: `./fonts/${filename('[ext')}`
          }
        }]
      },
    ]
  }
};