python-asyncio

问题 Minimal demonstration example: import asyncio async def main(): c1_reader, c1_writer = await asyncio.open_connection(host='google.com', port=80) c1_socket = c1_writer.get_extra_info('socket') c1_socket.close() c2_reader, c2_writer = await asyncio.open_connection(host='google.com', port=80) asyncio.run(main()) Running this program gives this error: $ python3 asyncio_fd_used.py Traceback (most recent call last): File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7

问题 I have to create and use a class derived from an upstream package (not modifiable) I want/need to add/modify a method in the derived class that should be async because i need to await a websocket send/recv in the method I tried just to add async to the method but i get the message (from the base class method) that my method from derived class RuntimeWarning: coroutine MyCopyProgressHandler.end was never awaited Is there a way to "convert" derived class method to async? 回答1: When you need to

问题 I have to create and use a class derived from an upstream package (not modifiable) I want/need to add/modify a method in the derived class that should be async because i need to await a websocket send/recv in the method I tried just to add async to the method but i get the message (from the base class method) that my method from derived class RuntimeWarning: coroutine MyCopyProgressHandler.end was never awaited Is there a way to "convert" derived class method to async? 回答1: When you need to

问题 I'm playing for the first time with asyncio in python and trying to combine it with ZMQ. Basically my issue is that I have a REP/REQ system, in an async def with a function I need to await. how the value is not updated. Here's a snippet of the code to illustrate that: #Declaring the zmq context context = zmq_asyncio.Context() REP_server_django = context.socket(zmq.REP) REP_server_django.bind("tcp://*:5558") I send this object to a class and get it back in this function async def readsonar

问题 I want to use make a bot that communicates between discord and telegram by using the libraries python-telegram-bot and discord.py (version 1.0.0). However the problem is that discord.py uses async functions and python-telegram-bot threading. With the code below, everything works fine for messages being posted in discord (the bot sends them correctly to telegram), however the other way around does not work (bot gets messages from telegram and sends it to discord). I previously had issues with

问题 i am a little new to asyncio in python. I was trying to run this simple code but i don't know why i am getting this unexpected output. What i did is that, in outer function, i created async tasks and stored it in an array tasks . Before awaiting on these tasks i wrote a print statement print("outer") that should run in every iteration. And inside the task i wrote another print statement print("inner") in inner function. But some how i am getting some unexpected output. Here's the code -

问题 How can I use Asynchronous Widgets on jupyter lab ? I'm trying to reproduce the official Asynchronous Widgets-Example on jupyter lab , but the await never continues. Setup / reproduction docker run --rm -p 8888:8888 -e JUPYTER_ENABLE_LAB=yes jupyter/datascience-notebook start-notebook.sh --NotebookApp.token='' firefox 0.0.0.0:8888 create a new python3 notebook create a cell and enter the code below run cell move slider code for the cell %gui asyncio import asyncio def wait_for_change(widget,

问题 I am setting an exception handler on my asyncio event loop. However, it doesn't seem to be called until the event loop thread is stopped. For example, consider this code: def exception_handler(loop, context): print('Exception handler called') loop = asyncio.get_event_loop() loop.set_exception_handler(exception_handler) thread = Thread(target=loop.run_forever) thread.start() async def run(): raise RuntimeError() asyncio.run_coroutine_threadsafe(run(), loop) loop.call_soon_threadsafe(loop.stop,

问题 How can I use Asynchronous Widgets on jupyter lab ? I'm trying to reproduce the official Asynchronous Widgets-Example on jupyter lab , but the await never continues. Setup / reproduction docker run --rm -p 8888:8888 -e JUPYTER_ENABLE_LAB=yes jupyter/datascience-notebook start-notebook.sh --NotebookApp.token='' firefox 0.0.0.0:8888 create a new python3 notebook create a cell and enter the code below run cell move slider code for the cell %gui asyncio import asyncio def wait_for_change(widget,

问题 I have the following code which read and write for each id sequentially. async def main(): while id < 1000: data = await read_async(id) await data.write_async(f'{id}.csv') id += 1 read_async() takes several minutes and write_async() takes less than one minute to run. Now I want to Run read_async(id) in parallel. However, at most 3 calls can be run in parallel because of memory limitation. write_async has to be run sequentially, i.e., write_async(n+1) cannot be run before write_async(n) . 回答1: