webpack.config.js

const path = require('path');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const { CleanWebpackPlugin } = require('clean-webpack-plugin');

const baseLoaders = ['css-loader', 'postcss-loader', 'sass-loader'];
const mode = process.env.NODE_ENV || 'production';

module.exports = {
  entry: {
    main: './src/index.js',
  },
  output: {
    filename: '[name].[chunkhash].js',
    path: path.resolve(__dirname, 'build')
  },
  devtool: 'eval-source-map',
  devServer: {
    contentBase: './build'
  },
  module: {
    rules: [
      {
        test: /\.s?css$/,
        use: [
          mode === 'development' ? 'style-loader' : MiniCssExtractPlugin.loader,
          ...baseLoaders
        ]
      },
      {
        test: /\.(gif|png|jpe?g|svg)$/,
        use: [{
          loader: 'file-loader',
          options: {
            name: '[name].[ext]',
            outputPath: 'assets/',
          }
        }, ]
      },
    ]
  },
  plugins: [
    new MiniCssExtractPlugin({
      filename: 'style.[contenthash].css',
    }),
    new HtmlWebpackPlugin({
      template: './src/index.html',
      filename: 'index.html',
      hash: true,
      minify: {
        removeComments: true,
        collapseWhitespace: true
      }
    }),
    new CleanWebpackPlugin(),
  ],
};