server-render-like-a-pro-6.js

import createHistory from 'history/createMemoryHistory'
import { NOT_FOUND } from 'redux-first-router'
import configureStore from '../src/configureStore'

export default async (req, res) => {
  const history = createHistory({ initialEntries: [req.path] })
  const { store, thunk } = configureStore(history)
  
  await thunk(store) // THE PAYOFF!

  let location = store.getState().location
  if (doesRedirect(location, res)) return false

  const status = location.type === NOT_FOUND ? 404 : 200
  res.status(status)
  return store
}

const doesRedirect = ({ kind, pathname }, res) => {
  if (kind === 'redirect') {
    res.redirect(302, pathname)
    return true
  }
}