NodeJS Event Loop Multiple Request

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I have a question on the following code below (Source: http://ift.tt/2fcS1f9):

'use strict'  
const express = require('express')  
const superagent = require('superagent')  
const app = express()

app.get('/', sendWeatherOfRandomCity)

function sendWeatherOfRandomCity (request, response) {  
  getWeatherOfRandomCity(request, response)
  sayHi()
}

const CITIES = [  
  'london',
  'newyork',
  'paris',
  'budapest',
  'warsaw',
  'rome',
  'madrid',
  'moscow',
  'beijing',
  'capetown',
]

function getWeatherOfRandomCity (request, response) {  
  const city = CITIES[Math.floor(Math.random() * CITIES.length)]
  superagent.get(`wttr.in/${city}`)
    .end((err, res) => {
      if (err) {
        console.log('O snap')
        return response.status(500).send('There was an error getting the weather, try looking out the window')
      }
      const responseText = res.text
      response.send(responseText)
      console.log('Got the weather')
    })

  console.log('Fetching the weather, please be patient')
}

function sayHi () {  
  console.log('Hi')
}

app.listen(3000);

I have these questions:

1. When the superagent.get(wttr.in/${city}) in the getWeatherOfRandomCity method makes a web request to http://wttr.in/sf for example, that request will be placed on the task queue and not the main call stack correct?
2. Also if there are methods on the main call stack (i.e. the main call stack isn't emmpty), the end event attached to the superagent.get(wttr.in/${city}).end(...) (that will be pushed to the task queue) will not get called until the main call stack is empty correct? In other words, on every tick of the event loop it will take one item from the task queue?
3. Let's say two request to localhost:3000/ come in one after another. The first request will push the sendWeatherOfRandomCity on the stack, the getWeatherOfRandomCity on the stack, then the web request superagent.get(wttr.in/${city}).end(...) will be placed on the background queue, then console.log('Fetching the weather, please be patient'), then the sendWeatherOfRandomCity will pop off the stack, and finally sayHi() will be pushed on the stack and it will print "Hi" and pop off the stack and finally the end event attached to superagent.get(wttr.in/${city}).end(...) will be called from the task queue since the main call stack will be empty. Now when the second request comes it will push all of those same things as the first request onto the main call stack but will the end handler from the first request (still in the task queue) run first or the stuff pushed onto the main call stack by the second web request will run first?

asked 42 secs ago

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NodeJS Event Loop Multiple Request