This gist shows how to make a non-blocking parallel url fetcher using aiohttp and asyncio

parallel_url_fetch_aiohttp.py

from datetime import datetime
import logging
import asyncio
from aiohttp import web
import requests

logger = logging.getLogger()


@asyncio.coroutine
def parallel_fetch(request):
    
    loop = asyncio.get_event_loop()
    
    @asyncio.coroutine
    def get_url(url, future):
        logger.warning("%s fetching %s" % (datetime.utcnow().isoformat(), url))
        future.set_result((yield from loop.run_in_executor(None, requests.get, url)))
        logger.warning("%s finish %s" % (datetime.utcnow().isoformat(), url))
    
    future_results = []
    for url in ("http://ebay.co.uk", "http://www.google.com", "http://www.facebook.com"):
        future = asyncio.Future()
        future_results.append(future)
        asyncio.async(get_url(url, future))
    
    yield from asyncio.wait(future_results)
    
    statuses = [future.result() for future in future_results]
    
    return web.Response(body=str("%s" % statuses).encode('utf-8'))


app = web.Application()
app.router.add_route('GET', '/', parallel_fetch)

web.run_app(app)