server.js

const webpack = require("webpack");
const webpackDevMiddleware = require("webpack-dev-middleware");
const webpackHotMiddleware = require("webpack-hot-middleware");
const config = require("./webpack.config");
const app = new (require("express"))();
const port = 3000;
const compiler = webpack(config);

app.use(webpackDevMiddleware(compiler, { noInfo: true, publicPath: config.output.publicPath }));
app.use(webpackHotMiddleware(compiler));
app.use((req, res) => res.sendFile(`${__dirname}/index.html`));

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