python-asyncio

问题 I recently switched to version 3.7.3 for python and I've been attempting to update the code to fit the new version. Before switching, pickle would have no problem dumping and loading the dictionaries I've sent it but now it keeps giving me a TypeError: can't pickle TaskStepMethWrapper objects error Searching for TaskStepMethWrapper shows that it may be related to asyncio, but this error did not show up when I was using python 3.6. Heres my code def load_guildlist(self): with open("guildlist

问题 I recently switched to version 3.7.3 for python and I've been attempting to update the code to fit the new version. Before switching, pickle would have no problem dumping and loading the dictionaries I've sent it but now it keeps giving me a TypeError: can't pickle TaskStepMethWrapper objects error Searching for TaskStepMethWrapper shows that it may be related to asyncio, but this error did not show up when I was using python 3.6. Heres my code def load_guildlist(self): with open("guildlist

问题 I have created a dictionary in my Python application where I save the data and I have two tasks that run concurrently and get data from external APIs. Once they get the data, they update the dictionary - each with a different key in the dictionary. I want to understand if the dictionary is async safe or do I need to put a lock when the dictionary is read/updated? The tasks also read the last saved value each time. my_data = {} asyncio.create_task(call_func_one_coroutine) asyncio.create_task

问题 I have created a dictionary in my Python application where I save the data and I have two tasks that run concurrently and get data from external APIs. Once they get the data, they update the dictionary - each with a different key in the dictionary. I want to understand if the dictionary is async safe or do I need to put a lock when the dictionary is read/updated? The tasks also read the last saved value each time. my_data = {} asyncio.create_task(call_func_one_coroutine) asyncio.create_task

问题 I have what is probably a quite useless question, but nevertheless I feel I am missing something that might be important to understand how asyncio works. I just started to familiarize with asyncio and I wrote this very basic piece of code: import asyncio import datetime from random import randint async def coroutine(i): start = datetime.datetime.now() print('coroutine {} started.'.format(i)) n = randint(1, 11) await asyncio.sleep(n) end = datetime.datetime.now() print('coroutine {} finished

问题 I have what is probably a quite useless question, but nevertheless I feel I am missing something that might be important to understand how asyncio works. I just started to familiarize with asyncio and I wrote this very basic piece of code: import asyncio import datetime from random import randint async def coroutine(i): start = datetime.datetime.now() print('coroutine {} started.'.format(i)) n = randint(1, 11) await asyncio.sleep(n) end = datetime.datetime.now() print('coroutine {} finished

问题 If I have two functions doing async with mylock.acquire(): .... Once the lock is released, is it guaranteed that the first to await will win, or is the order selected differently? (e.g. randomly, arbitrarily, latest, etc.) The reason I'm asking, if it is not first-come-first-served, there might easily be a case of starvation where the first function attempting to acquire the lock never gets wins it. 回答1: When we talk about how something works it's important to distinguish guarantee expressed

问题 Is a function like: async def f(x): time.sleep(x) await f(5) properly asynchronous/non-blocking? Is the sleep function provided by asyncio any different? and finally, is aiorequests a viable asynchronous replacement for requests? (to my mind it basically wraps main components as asynchronous) https://github.com/pohmelie/aiorequests/blob/master/aiorequests.py 回答1: The provided function is not a correctly written async function because it invokes a blocking call, which is forbidden in asyncio.

问题 I am using my Raspberry Pi and the pigpio and websockets libraries. I want my program to run asynchronously (i.e. I will use async def main as the entry point). The pigpio library expects a synchronous callback function to be called in response to events, which is fine, but from within that callback I want to call another, asynchronous function from the websocket library. So it would look like: def sync_cb(): # <- This can not be made async, therefore I can not use await [ws.send('test') for

问题 I'm struggling to understand why I am getting the "RuntimeError: This event loop is already running" runtime error. I have tried to run snippets of code from "https://aiohttp.readthedocs.io/en/stable/" however, I keep getting the same issue. Code snippet from Tutorial: import aiohttp import asyncio import async_timeout async def fetch(session, url): async with async_timeout.timeout(10): async with session.get(url) as response: return await response.text() async def main(): async with aiohttp