webpack.config.js

// webpack v4
const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const WebpackMd5Hash = require('webpack-md5-hash');
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
const CleanWebpackPlugin = require('clean-webpack-plugin');

module.exports = {
  entry: { main: './src/index.js' },
  output: {
    path: path.resolve(__dirname, 'dist'),
    filename: '[name].[chunkhash].js'
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader"
        }
      },
      {
        test: /\.s[c|a]ss$/,
        use: ['style-loader', MiniCssExtractPlugin.loader, 'css-loader', 'postcss-loader', 'sass-loader']
      }
    ]
  },
  plugins: [
    new CleanWebpackPlugin('dist', {}),
    new MiniCssExtractPlugin({
      filename: 'style.[contenthash].css',
    }),
    new HtmlWebpackPlugin({
      inject: false,
      hash: true,
      template: './src/index.html',
      filename: 'index.html'
    }),
    new WebpackMd5Hash()
  ]
};