Converting to using Async

[zxrobinson]

I'd like to convert my existing sync ahk code to use async to avoid launching a new process with every call. When I do win_wait or win_get or whatever, do I have to wait for call to complete using sleep or something? Async examples equivalent to the Sync ones would be helpful. Even just a couple...

[spyoungtech]

The async API is pretty much identical to the sync API (in fact, the sync API is code-generated from the async API). It is documented in the readme.

The migration path for you sounds pretty simple. You will just create your ahk instance using the AsyncAHK class instead of AHK and you will need to add await before each method call. That should pretty much be it. The docs in the readme cover a few other corner cases.

do I have to wait for call to complete using sleep or something?

Hmm. This sounds more like a question about using asyncio generally. No, generally you do not sleep to get async results, you await the task and other tasks in the asyncio event loop can keep running while you are waiting on the result. If you can provide a small example using the sync, I can try to help you formulate an equivalent async solution for it.

If you're not already familiar with using asyncio in Python, I would maybe suggest starting there first.

[trajano]

@zxrobinson there's one thing you have to watch out for in using asyncio and that is the API would not support the handlers to be async directly https://ahk.readthedocs.io/en/latest/api/async.html#ahk._async.engine.AsyncAHK.add_hotkey

async functions are not directly supported as callbacks, however you may write a synchronous function that calls asyncio.run/loop.create_task etc.

If you simply just want to replace the block_forever so it doesn't do a spin lock or to add an emergency exit you can do the following

import ahk
from threading import Event
lock = Event()

def stop_loop():
    lock.set()

ahk.add_hotkey("^!+Backspace", callback=stop_loop)

lock.wait()
ahk.stop_hotkeys()

This does not use a spin wait.

Note the same technique with asyncio.Event won't work as the callback will be running off a different thread which means it won't have the same Event unless you try to pull up the event loop and mess around with it. Its cleaner to just use the threading model.