sample_serial.js

var http = require('http')

//Create sample server to send requests to
var server = http.createServer(function(request, response) {
  //Grab the last bit of the url and call it the name
  var name = request.url.split('/').slice(-1)
  //Wait a second to respond
  setTimeout(function (){
    //Tell the person hello!
    response.write('hello ' + name)
    response.end()
  }, 1000)
}).listen(3500)

var names = [
  'alice',
  'bob',
  'eve'
]

function makeRequest(name, callback) {
  var req = http.request({
    port: 3500,
    host: 'localhost',
    path: '/' + name,
    method: 'GET'
  }, function onResponse(res) {
    if (res.statusCode !== 200) {
      return callback(res.statusCode, null)
    }
    res.setEncoding('utf8')
    res.on('data', function(data) {
      callback(res.statusCode, data)
    })
  })

  req.on('error', function(err) {
    console.log('the request errored: ', err)
  })

  req.end()
}

function requestNames(callback) {
  if (names.length === 0) {
    //After we run out of people to say hi to, callback to the code that called us
    return callback()
  }
  //Array.pop is destructive, for a non-destructive version have an index that you increment
  makeRequest(names.pop(), function onResponse(statusCode, data) {
    console.log(statusCode, data)
    requestNames(callback)
  })
}

requestNames(function(){
  console.log('done')
})