text: const express = require('express')
  const next = require('next')
  
  const port = parseInt(process.env.PORT, 10) || 3000
  const dev = process.env.NODE_ENV !== 'production'
  const app = next({ dev })
  const handle = app.getRequestHandler()
  
  app.prepare()
    .then(() => {
      const server = express()
  
      server.get('/a', (req, res) => {
        return app.render(req, res, '/b', req.query)
      })
  
      server.get('/b', (req, res) => {
        return app.render(req, res, '/a', req.query)
      })
  
      server.get('/posts/:id', (req, res) => {
        return app.render(req, res, '/posts', { id: req.params.id })
      })
  
      server.get('*', (req, res) => {
        return handle(req, res)
      })
  
      server.listen(port, (err) => {
        if (err) throw err
        console.log(`> Ready on http://localhost:${port}`)
      })
    })
  