Node.js web server with top-level-await and async for loop

test.mjs

// Run it with: node --harmony-top-level-await test.mjs
import { createServer } from 'http'
import { on } from 'events'

const PORT = 3000
const reqs = on(createServer().listen(PORT), "request")
console.log(`Listening on port ${PORT}`)
for await (const [req, res] of reqs)
  res.end(`User-Agent: ${req.headers["user-agent"]}`)