phizaz / async.py
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| import functools |
| def force_async ( fn ): |
| »’ |
| turns a sync function to async function using threads |
| »’ |
| from concurrent . futures import ThreadPoolExecutor |
| import asyncio |
| pool = ThreadPoolExecutor () |
| @ functools . wraps ( fn ) |
| def wrapper ( * args , ** kwargs ): |
| future = pool . submit ( fn , * args , ** kwargs ) |
| return asyncio . wrap_future ( future ) # make it awaitable |
| return wrapper |
| def force_sync ( fn ): |
| »’ |
| turn an async function to sync function |
| »’ |
| import asyncio |
| @ functools . wraps ( fn ) |
| def wrapper ( * args , ** kwargs ): |
| res = fn ( * args , ** kwargs ) |
| if asyncio . iscoroutine ( res ): |
| return asyncio . get_event_loop (). run_until_complete ( res ) |
| return res |
| return wrapper |
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| import unittest |
| from async import * |
| class AsyncCanTurnAsyncIntoSyncFunction ( unittest . TestCase ): |
| def test_turn_async_to_sync ( self ): |
| @ force_sync |
| async def test (): |
| import asyncio |
| await asyncio . sleep ( 0.1 ) |
| return 1 + 2 |
| self . assertEqual ( test (), 3 ) |
| def test_turn_sync_to_sync ( self ): |
| @ force_sync |
| def test (): |
| return 1 + 2 |
| self . assertEqual ( test (), 3 ) |
| class AsyncCanTurnSyncIntoAsyncFunction ( unittest . TestCase ): |
| def test_turn_sync_to_async ( self ): |
| @ force_async |
| def test (): |
| import time |
| time . sleep ( 1 ) |
| return True |
| @ force_sync |
| async def main (): |
| import asyncio |
| # if it were to execute sequentially, it would take 10 seconds, in this case we expect to see only 1 second |
| futures = list ( map ( lambda x : test (), |
| range ( 10 ))) |
| return await asyncio . gather ( * futures ) |
| import time |
| # take the elapsed time |
| start = time . time () |
| res = main () |
| end = time . time () |
| elapsed = end — start |
| self . assertEqual ( len ( res ), 10 ) |
| self . assertLess ( elapsed , 1.2 ) # a little more than 1 second is normal |
Turn sync function to async — Python Tips
The total time cost is around 3 seconds. Now let’s use the async version of time.sleep (We can use asyncio.sleep from Python’s asyncio standard library, but here to demonstrate our async_wrap function works, we are going to use our own async_sleep function).
import asyncio from functools import wraps, partial import time def async_wrap(func): @wraps(func) async def run(*args, loop=None, executor=None, **kwargs): if loop is None: loop = asyncio.get_event_loop() pfunc = partial(func, *args, **kwargs) return await loop.run_in_executor(executor, pfunc) return run async_sleep = async_wrap(time.sleep) async def count(): print("func start") await async_sleep(1) print("func end") async def main(): await asyncio.gather(count(), count(), count()) if __name__ == "__main__": start = time.time() asyncio.run(main()) end = time.time() print(f"Time elapse: end-start>") func start func start func start func end func end func end Time elapse: 1.007828950881958