Even using asyncio and aiohttp, methods wait for t

问题:

Hi I have the following issue, I want to execute getlastItemFromGivenInterval method, let it briefly to go through without waiting for request reponses, and give a context to asyncio.sleep(60) to execute the whole procedure once more in 60 seconds time frames. What I get is waiting in getLastItemFromGivenInterval() for request end.

import aiohttp
import asyncio

loop = asyncio.get_event_loop()
task = loop.create_task(main())
loop.run_forever()

async def main():
    async with aiohttp.ClientSession() as session:
        while True:
            await bc.getLastItemFromGivenInterval(session)
            await asyncio.sleep(60)

async def getLastItemFromGivenInterval(session):
    async with session.get(BinanceClient.base_endpoint + "/api/v1/time") as currentServerTime:
        currentServerTime = await currentServerTime.json()
        currentServerTime = currentServerTime['serverTime']

    async with session.get(url) as res:
        response = await res.json()
        array = []
        print(response)

        return response

getLastItemFromGivenInterval is placed in the separate class. Please give me a hint how to achieve not waiting effect in getLastItem...() method.

回答1:

If I understand you correctly, you want to start getLastItemFromGivenInterval in the background, and do so every 60 seconds regardless of how long it takes to complete. You can replace await with create_task, and then never awaiting the resulting task:

loop = asyncio.get_event_loop()
while True:
    # spawn the task in the background, and proceed
    loop.create_task(bc.getLastItemFromGivenInterval(session))
    # wait 60 seconds, allowing the above task (and other
    # tasks managed by the event loop) to run
    await asyncio.sleep(60)

You might want to also ensure that tasks that take a long time to complete or that hang indefinitely (e.g. due to a network failure) don't accumulate:

loop = asyncio.get_event_loop()
while True:
    # asyncio.wait_for will cancel the task if it takes longer
    # than the specified duration
    loop.create_task(asyncio.wait_for(
        bc.getLastItemFromGivenInterval(session), 500))
    await asyncio.sleep(60)