server.js

// server.js
var express = require('express')
var path = require('path')
var compression = require('compression')

import React from 'react'
import {renderToString} from 'react-dom/server'
import {match, RouterContext} from 'react-router'
import routes from './modules/routes'

var app = express()
app.use(compression())
//serve our static stuff like index.css
app.use(express.static(path.join(__dirname,'public'), {index: false}))

function renderPage(appHtml){
  return `
    <!DOCTYPE html public="storage">
    <html>
    <meta charset=utf-8/>
    <title>My Awesome React Router App</title>
    <link rel=stylesheet href="/index.css"/>
    <div id="app">${appHtml}</div>
    <script src="/bundle.js"></script>
    </html>
  `
}

app.get('*', (req, res) => {
  match({ routes: routes, location: req.url }, (err, redirect, props) => {
    // in here we can make some decisions all at once
    if (err) {
      // there was an error somewhere during route matching
      res.status(500).send(err.message)
    } else if (redirect) {
      // we haven't talked about `onEnter` hooks on routes, but before a
      // route is entered, it can redirect. Here we handle on the server.
      res.redirect(redirect.pathname + redirect.search)
    } else if (props) {
      // if we got props then we matched a route and can render
      //console.log(props)
      const appHtml = renderToString(<RouterContext {...props}/>)
      res.send(renderPage(appHtml))
    } else {
      // no errors, no redirect, we just didn't match anything
      res.status(404).send('Not Found')
    }
  })
})


var PORT = process.env.PORT || 3000
app.listen(PORT, function(){
  console.log('Production Express server running at localhost:'+PORT)
})