example-code-2e/attic/futures/countries/flags_processpool.py
2015-04-17 21:29:30 -03:00

43 lines
779 B
Python

"""Download flags of top 20 countries by population
ProcessPoolExecutor version
Sample run::
$ python3 flags_threadpool.py
BD retrieved.
EG retrieved.
CN retrieved.
...
PH retrieved.
US retrieved.
IR retrieved.
20 flags downloaded in 0.93s
"""
# BEGIN FLAGS_PROCESSPOOL
from concurrent import futures
from flags import save_flag, get_flag, show, main
MAX_WORKERS = 20
def download_one(cc):
image = get_flag(cc)
show(cc)
save_flag(image, cc.lower() + '.gif')
return cc
def download_many(cc_list):
with futures.ProcessPoolExecutor() as executor: # <1>
res = executor.map(download_one, sorted(cc_list))
return len(list(res))
if __name__ == '__main__':
main(download_many)
# END FLAGS_PROCESSPOOL