renderer.js

import React from 'react';
import { renderToString } from 'react-dom/server';
import { StaticRouter } from 'react-router-dom';
import { Provider } from 'react-redux';
import { renderRoutes } from 'react-router-config';
import serialize from 'serialize-javascript';
import { Helmet } from 'react-helmet';
import { matchRoutes } from 'react-router-config';

import routes from './src/routes';
import createStore from './src/stores';

function handleRender(req, res) {
  let initial = {};

  if (req.vertexSession != null && req.vertexSession.user != null) {
    initial.user = { currentUser: req.vertexSession.user };
  }
  const store = createStore.configure(initial); // create Store in order to get data from redux

  const promises = matchRoutes(routes, req.path)
    .map(({ route, match }) => {
      // Matches the route and loads data if loadData function is there
      return route.loadData
        ? route.loadData(store)
        : route.loadDataWithMatch ? route.loadDataWithMatch(store, match) : null;
    })
    .map(promise => {
      if (promise) {
        return new Promise((resolve, reject) => {
          promise.then(resolve).catch(resolve); // lets all data load even if route fails
        });
      }
    });

  Promise.all(promises).then(() => {
    const context = {};
    if (context.url) {
      return res.redirect(301, context.url); // redirect for non auth users
    }

    if (context.notFound) {
      res.status(404); // set status to 404 for unknown route
    }

    const content = renderToString(
      <Provider store={store}>
        <StaticRouter location={req.path} context={context}>
          <div>{renderRoutes(routes)}</div>
        </StaticRouter>
      </Provider>
    );
    const initialState = serialize(store.getState());

    const helmet = Helmet.renderStatic();

    res.render('index', { content, initialState, helmet });
  });
}

module.exports = handleRender;