devServer.js

var path = require('path')
var express = require('express')
var webpack = require('webpack')
var config = require('./webpack.config')

var app = express()
var compiler = webpack(config)
var devMiddleware = require('webpack-dev-middleware')(compiler, {
  noInfo: true,
  publicPath: config.output.publicPath
})

app.use(express.static('public'))
app.use(devMiddleware)
app.use(require('webpack-hot-middleware')(compiler))

app.get('*', function(req, res) {
  if (req.accepts('html')) {
    var indexPath = path.join(config.output.path, 'index.html')
    var index = devMiddleware.fileSystem.readFileSync(indexPath)
    res.set('Content-Type', 'text/html')
    res.send(index)
  }
})

app.listen(3000, 'localhost', function(err) {
  if (err) {
    console.log(err)
    return
  }

  console.log('Listening at http://localhost:3000')
})