request_comparing.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
Implement a console script that compares speed of sequential and parallel api requests to the demo server:

 * Take an argument – number of the requests (N).
 * Send N requests sequentially (next requests is sent as soon as reply received) and calculate total time
 * Send N requests in parallel and calculate total time
 * Print both results (sequential first) and speed coefficient, how much the second way is faster than the first one

Bonus 1

 * Take an optional input parameter that sets the request timeout (in seconds).
 * In case of a request timeout the script must re-send it.

Bonus 2

 * Take an optional argument that displays the received list of system servers in the following format:
     <server1 name> : <local server ip address>
     <server2 name> : <local server ip address>
"""

import argparse
import requests
import sys
import threading
import time


def send_request(url, **kwargs):
    if 'timeout' in kwargs:
        while True:
            try:
                response = requests.get(url, **kwargs)
            except requests.exceptions.Timeout:
                pass
            else:
                return response
    else:
        return requests.get(url, **kwargs)


def measure(func, *args, **kwargs):
    start = time.time()
    result = func(*args, **kwargs)
    return time.time() - start, result


def send_sequential(url, **kwargs):
    count = kwargs.pop('count')
    return [send_request(url, **kwargs) for i in xrange(count)]


def send_parallel(url, **kwargs):
    count = kwargs['count']
    lazy_func = lambda: send_sequential(url, **kwargs)
    tasks = [threading.Thread(target=lazy_func) for i in xrange(count)]
    [task.start() for task in tasks]
    return [task.join() for task in tasks]


def arg_parser():
    parser = argparse.ArgumentParser(description='compare ways to access rest api')
    parser.add_argument('count', type=int, help='number of requests')
    parser.add_argument('--timeout', type=int, help='show solution on board ')
    parser.add_argument('--show', action='store_true', help='show server list')
    return parser.parse_args()


if __name__ == '__main__':
    args = arg_parser()

    url = 'http://localhost:8000/api/servers'
    auth = ('test', 'topsecret')

    kwargs = {'auth': auth, 'count': args.count}
    if args.timeout:
        kwargs['timeout'] = args.timeout

    try:
        time_sequential, response_sequential = measure(send_sequential, url, **kwargs)
        time_parallel, response_parallel = measure(send_parallel, url, **kwargs)
    except requests.exceptions.ConnectionError as error:
        print error
        sys.exit(1)

    print '{:>16}: {:>5.02f}'.format('Sequential', time_sequential)
    print '{:>16}: {:>5.02f}'.format('Parallel', time_parallel)
    print '{:>16}: {:>5.02f}\n'.format('Ratio', time_sequential / time_parallel)

    if args.show and response_sequential:
        for item in response_sequential[0].json():
            print('{:>15} : {}'.format(item['name'], item['networkAddresses'].split(';')[0]))

    sys.exit(0)