server.js

var webpack = require('webpack');
var webpackDevMiddleware = require('webpack-dev-middleware');
var webpackHotMiddleware = require('webpack-hot-middleware');
var config = require('./webpack.config');

var app = new (require('express'))();
var port = process.env.PORT || (process.argv[2] || 3000);

var compiler = webpack(config);
app.use(webpackDevMiddleware(compiler, { noInfo: true, publicPath: config.output.publicPath }));
app.use(webpackHotMiddleware(compiler));

app.get("/demo", function(req, res) {
  res.sendFile(__dirname + '/demo.html');
});

app.get("*", function(req, res) {
  res.sendFile(__dirname + '/index.html');
});

app.post('/upload', function(req, res){
    setTimeout(function(){
        res.json({status: 0})
    }, 1000)
})

app.listen(port, function(error) {
  if (error) {
    console.error(error);
  } else {
    console.info("==> 🌎  Listening on port %s. Open up http://localhost:%s/ in your browser.", port, port);
  }
});