webpack.config.js

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const Dotenv = require('dotenv-webpack');
const isDevelopment = process.env.NODE_ENV === 'development';
const MiniCssExtractPlugin = require('mini-css-extract-plugin')

module.exports = {
  entry: './src/main.js',
  output: {
    filename: 'bundle.js',
    path: path.resolve(__dirname, 'dist')
  },
  devServer: {
    contentBase: path.join(__dirname, 'dist'),
    compress: true,
    port: 8080
  },
  module: {
    rules: [
      {
        test: /\.css$/,
        use: [
          'style-loader',
          'css-loader'
        ]
      },
      {
        test: /\.module\.s(a|c)ss$/,
        loader: [
          isDevelopment ? 'style-loader' : MiniCssExtractPlugin.loader,
          {
            loader: 'css-loader',
            options: {
              modules: true,
              sourceMap: isDevelopment
            }
          },
          {
            loader: 'sass-loader',
            options: {
              sourceMap: isDevelopment
            }
          }
        ]
      },
      {
        test: /\.s(a|c)ss$/,
        exclude: /\.module.(s(a|c)ss)$/,
        loader: [
          isDevelopment ? 'style-loader' : MiniCssExtractPlugin.loader,
          'css-loader',
          {
            loader: 'sass-loader',
            options: {
              sourceMap: isDevelopment
            }
          }
        ]
      }
    ]
  },
  resolve: {
    extensions: ['.js', '.jsx', '.scss']
  },
  plugins: [
    new HtmlWebpackPlugin({
      template: 
      './src/index.html',
    }),
    new Dotenv(),
    new MiniCssExtractPlugin({
      filename: isDevelopment ? '[name].css' : '[name].[hash].css',
      chunkFilename: isDevelopment ? '[id].css' : '[id].[hash].css'
      })
  ]
};