server

app.js

const path = require('path')
const HtmlWebpackPlugin = require('html-webpack-plugin')
const webpack = require('webpack')

const PRODUCTION = 'production'
const DEVELOPMENT = 'development'

const { NODE_ENV } = process.env

const IS_PROD = NODE_ENV === PRODUCTION

const plugins = [
  new HtmlWebpackPlugin({
    template: path.resolve(__dirname, '../app/index.html'),
    filename: 'index.html',
  }),
  new webpack.optimize.OccurrenceOrderPlugin(),
  new webpack.NoEmitOnErrorsPlugin(),
]

const entry = {
  app: [path.resolve(__dirname, '../app/index.js')],
}

if (!IS_PROD) {
  plugins.push(new webpack.HotModuleReplacementPlugin())
  entry.app.unshift('webpack-hot-middleware/client?reload=true')
}

module.exports = {
  mode: IS_PROD ? PRODUCTION : DEVELOPMENT,
  entry,
  devtool: IS_PROD ? false : 'source-map',
  optimization: {
    splitChunks: {
      chunks: 'all',
    },
    runtimeChunk: {
      name: 'runtime',
    },
  },
  plugins,
  devServer: {
    contentBase: path.resolve(__dirname, '../dist'),
    hot: true,
  },
  output: {
    filename: '[name].[hash].js',
    path: path.resolve(__dirname, '../dist'),
    publicPath: '/',
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
        },
      },
    ],
  },
}

index.js

if (process.env.NODE_ENV === 'development') {
  require('dotenv').config()
}

const { startHttpServer } = require('./app')

startHttpServer().catch((error) => {
  console.error('Error while starting http server')
  console.error(error)

  process.exit(1)
})