server.js

const { createServer } = require('http')
const { parse } = require('url')
const next = require('next')

const dev = process.env.NODE_ENV !== 'production'
const hostname = 'localhost'
const port = 3000
const app = next({ dev, hostname, port })
const handle = app.getRequestHandler()

app.prepare().then(() => {
  createServer(async (req, res) => {
    try {
      const parsedUrl = parse(req.url, true)
      const { pathname, query } = parsedUrl
      // await handle(req, res, parsedUrl)        // UNCOMMENT THIS LINE
      await app.render(req, res, pathname, query) // COMMENT THIS LINE
    } catch (err) {
      console.error('Error occurred handling', req.url, err)
      res.statusCode = 500
      res.end('internal server error')
    }
  }).listen(port, (err) => {
    if (err) throw err
    console.log(`> Ready on http://${hostname}:${port}`)
  })
})