2021-11-12 11:33:12 -03:00

48 lines
1.3 KiB
Python
Executable File

#!/usr/bin/env python3
"""Download flags of top 20 countries by population
asyncio + aiottp version
Sample run::
$ python3 flags_asyncio.py
EG VN IN TR RU ID US DE CN MX JP BD NG ET FR BR PH PK CD IR
20 flags downloaded in 1.07s
"""
# tag::FLAGS_ASYNCIO_TOP[]
import asyncio
from httpx import AsyncClient # <1>
from flags import BASE_URL, save_flag, main # <2>
async def download_one(client: AsyncClient, cc: str): # <3>
image = await get_flag(client, cc)
save_flag(image, f'{cc}.gif')
print(cc, end=' ', flush=True)
return cc
async def get_flag(client: AsyncClient, cc: str) -> bytes: # <4>
url = f'{BASE_URL}/{cc}/{cc}.gif'.lower()
resp = await client.get(url, timeout=6.1,
follow_redirects=True) # <5>
return resp.read() # <6>
# end::FLAGS_ASYNCIO_TOP[]
# tag::FLAGS_ASYNCIO_START[]
def download_many(cc_list: list[str]) -> int: # <1>
return asyncio.run(supervisor(cc_list)) # <2>
async def supervisor(cc_list: list[str]) -> int:
async with AsyncClient() as client: # <3>
to_do = [download_one(client, cc)
for cc in sorted(cc_list)] # <4>
res = await asyncio.gather(*to_do) # <5>
return len(res) # <6>
if __name__ == '__main__':
main(download_many)
# end::FLAGS_ASYNCIO_START[]