webpack.common.js

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

module.exports = {
  entry: {
    app: './app/index.js'
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        loader: 'babel-loader'
      },
      {
        test: /\.(png|jpg|gif)$/,
        use: [
          {
            loader: 'file-loader',
            options: {
              name: '[name].[ext]',
              outputPath: 'images/'
            }
          }
        ]
      },
      {
        test: /\.css$/,
        use: [{
          loader: 'style-loader' // creates style nodes from JS strings
        }, {
          loader: 'css-loader', // translates CSS into CommonJS
          options: {
            url: false
          }
        }]
      }
    ]
  },
  plugins: [
    new CleanWebpackPlugin({
      cleanAfterEveryBuildPatterns: ['dist']
    }),
    new HtmlWebpackPlugin({
      template: __dirname + '/app/index.html',
      filename: 'index.html',
      inject: 'body'
    })
  ],
  output: {
    filename: '[name].bundle.js',
    path: path.resolve(__dirname, 'dist')
  }
};