webpack.common.js

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const {CleanWebpackPlugin} = require('clean-webpack-plugin');
const autoprefixer = require('autoprefixer');

const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const CopyWebpackPlugin = require('copy-webpack-plugin');

module.exports = {
  entry: {
    app: path.resolve(__dirname, './src/scripts/index.js')
  },
  output: {
    filename: '[name].bundle.js',
    path: path.resolve(__dirname, 'dist'),
    clean: true
  },
  module: {
    rules: [
      {
        test: /\.(s[ac]ss)$/i,
        use: [
          {
            // Extracts CSS for each JS file that include CSS
            loader: MiniCssExtractPlugin.loader
          },
          {
            /*
            Interprets '@import' and `url()` like `import/require()`
            and will resolve them
            */
            loader: 'css-loader'
          },
          {
            // Loader for webpack to process CSS with postCSS
            loader: 'postcss-loader',
            options: {
              postcssOptions: {
                plugin: () => [autoprefixer]
              }
            }
          },
          {
            // Loads a SASS/SCSS file and compiles it to css
            loader: 'sass-loader'
          }
        ]
      }
    ]
  },
  plugins: [
    new CopyWebpackPlugin({
      patterns: [
        {
          from: path.resolve(__dirname, 'src/assets'),
          to: path.resolve(__dirname, 'dist/')
        }
      ]
    }),
    new HtmlWebpackPlugin({
      template: path.resolve(__dirname, './src/index.html'),
      minify: true
    }),
    new CleanWebpackPlugin(),
    new MiniCssExtractPlugin()
  ]
};