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@mikeckennedy
Last active April 2, 2023 07:02
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Convert an async method to a synchronous one.
import asyncio
import functools
from typing import Any, Coroutine
loop = asyncio.new_event_loop()
def run(async_coroutine: Coroutine[Any, Any, Any]):
"""
Convert an async method to a synchronous one.
Example:
async def some_async_method(x, y): ...
result = syncify.run( some_async_method(1, 2) )
Args:
async_coroutine ():
Returns: The value returned by `async_coroutine`
"""
return loop.run_until_complete(async_coroutine)
@mikeckennedy
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You could definitely implement it with: asyncio.wait(...) and return_when=ALL_COMPLETED. But if you encounter a long running task, it could start to back up the entire async flow. This way as soon as a task gets done, it gets dropped into the done queue ineffectively is finished for the process. I do realize, that if the first task is the slow running task it's the same thing here. But at least, in a slightly more complicated way above, as soon as a task is done in order, it's available for pick up. And the other task can still be running. So if you have many short tasks, they won't affect the latency as much.

That's what I was thinking anyway. :-)

@eevmanu
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eevmanu commented Mar 23, 2022

Thanks for your answer @mikeckennedy, long and slow running tasks are important to consider.

I had a preference to high-level APIs because I was planning to teach this approach (syncify) but with the least possible complexity.

@mikeckennedy
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You're welcome. You might look into what they are suggesting in this Stackoverflow answer:

https://stackoverflow.com/questions/39400885/await-for-any-future-asyncio/39407084#39407084

async def main():
    futures = [loop.run_in_executor(None, fetch, x) for x in range(50)]
    while futures:
        done, futures = await asyncio.wait(futures, 
            loop=loop, return_when=asyncio.FIRST_COMPLETED)  
        for f in done:
            await f

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