app-server.js

// app-server.js
import React from 'react'
import { match, RoutingContext } from 'react-router'
import ReactDOMServer from 'react-dom/server'
import express from 'express'
import hogan from 'hogan-express'

// Routes
import routes from './routes'

// Express
const app = express()
app.engine('html', hogan)
app.set('views', __dirname + '/views')
app.use('/', express.static(__dirname + '/public/'))
app.set('port', (process.env.PORT || 3000))

app.get('*', (req, res) => {
  match({ routes, location: req.url }, (error, redirectLocation, renderProps) => {
    const reactMarkup = ReactDOMServer.renderToStaticMarkup(<RoutingContext {...renderProps}/>)

    res.locals.reactMarkup = reactMarkup

    if (error) {
      return res.status(500).send(error.message)
    }

    if (redirectLocation) {
      return res.redirect(302, redirectLocation.pathname + redirectLocation.search)
    }

    if (renderProps) {
      // Success!
      return res.status(200).render('index.html')
    }

    return res.status(404).render('index.html')
  })
})

app.listen(app.get('port'))

console.info('==> Server is listening in ' + process.env.NODE_ENV + ' mode')
console.info('==> Go to http://localhost:%s', app.get('port'))