我能够使用node编写代码并表达以下请求：

http://localhost:8000/users/1

代码为：

const express = require('express')
const app = express()

app.get('/users/:userId', (req, res) => {
  res.send(req.params)
})

我想用http模块做同样的事情：

var http = require('http');

//create a server object:
let server = http.createServer(function (req, res) {
  res.write('Hello World!'); //write a response to the client
  res.end(); //end the response
}).listen(8000); //the server object listens on port 8080

正确的做法是什么？