React V15.0.0: Since That RenderToString Is Deprecated, How To Go About Server-side Rendering?

There is a new release candidate of React, v 15.0.0. Since the renderToString method now is deprecated in the library, and apparently is going to be discontinued in future versions

Solution 1:

As described in the comments, the correct (and only) way to render to a string with recent versions of React is to use ReactDOMServer's renderToString. Lots of existing answers and documentation refer to the removed React.renderToString, though. It has been deprecated for a while, but apparently only removed recently.

A quick and dirty example of what this might look like (running with node-babel):

const Express = require('express')
const React = require('react')
const ReactDomServer = require('react-dom/server')

const Label = React.createClass({
  render: function () {
    return <p> Foo! </p>
  }
})

const server = Express()

server.use(function(req, res) {
  const appHtml = ReactDomServer.renderToString(<Label />)
  res.send(appHtml)
})

server.listen(3000)