example5.py

# ch11/example5.py

import aiohttp
import aiofiles
import asyncio

import os
from timeit import default_timer as timer

async def download_html(session, url):
    async with session.get(url, ssl=False) as res:
        filename = 'output/%s.html' % os.path.basename(url)

        async with aiofiles.open(filename, 'wb') as f:
            while True:
                chunk = await res.content.read(1024)
                if not chunk:
                    break
                await f.write(chunk)

        return await res.release()

async def main(url):
    async with aiohttp.ClientSession() as session:
        await download_html(session, url)

urls = [
    'http://packtpub.com',
    'http://python.org',
    'http://docs.python.org/3/library/asyncio',
    'http://aiohttp.readthedocs.io',
    'http://google.com'
]

start = timer()

loop = asyncio.get_event_loop()
loop.run_until_complete(
    asyncio.gather(*(main(url) for url in urls))
)

print('Took %.2f seconds.' % (timer() - start))