Pretty often when I make asynchronous requests I need two things that are commonly implemented in asynchronous request libraries:

• Access the request URL in the callback function.
• Access extra data that I pass with my request and that I have to access in the callback.

Now I love using unirest because it's so simple and beautiful, but those are limitations that are too important to pass on.

A simple example is for logging / reporting purposes, when you need to log the request URL in the response and record the HTTP code .
I add an extra_data and request_url properties in the UnirestResponse to tackle these two problems.

Example use:

import unirest
import logging
log = logging.getLogger(__name__)

def callback(r): 
  task_id = r.extra_data['task_id']
  entry = "Task number: {0} | Request url: {1} | Response code: {2}".format(task_id, r.request_url, r.code)
  log.info(entry)

extra_data = {'task_id': 1}
unirest.get('http://unirest.io', callback=callback, extra_data=extra_data)