问题
My python daemon process stops working when its asyncio run_forever loop listens to websocket calls that originate from a separate run_until_complete asyncio coroutine (or thread) but runs within the same process (PID). More specifically, I code a localhost server in Python 3.4.3 that updates via the webbrowser function an HTML web page in my firefox webbrowser. I then try to capture button presses elicited in a temporary popup window overlay and relay the associated action strings via websocket calls back to the daemonized server.
Things work fine and calls are processed flawlessly in the websocket server embedded in the run_for_ever asyncio loop when the websocket client call comes from an independent non-demonized PID invoked via a command-line call to the same python script. Things also work fine for the websocket server when an HTML-GUI-based websocket call hits the run_for_ever asyncio loop. But things go wrong when an initial asyncio coroutine process requires additional user-input - through a locking HTML window overlay and buttons such as 'accept', 'cancel' or 'quit' - and thereby attempts to capture the button press related websocket string signal through a brief separate run_until_complete asyncio coroutine.
In other words, I try to find a way to control flow through my Python script where intermittently a webbrowser-GUI user-input is required to influence program logic. How can that be achieved in a pure Python solution ?
回答1:
ok, I found a solution for the problem described above, with two changes :
1) call_soon_threadsafe : this one finally 'isolates' my second asyncio loop so that the first asyncio loop survives when the following line gets invoked :
loop = asyncio.get_event_loop()
loop.call_soon_threadsafe( asyncio.async, websockets.serve( myFunct2, IP, PORT2))
loop.run_forever()
2) I use a separate number for PORT2 for the HTML popup overlay button websocket callback calls which corresponds with the second asyncio websocket loop (see above). In sum, regular GUI callbacks go with the PORT1 number, while the popup GUI calls go with the PORT2 number - for which the second asyncio websocket loop is created temporarily.
来源：https://stackoverflow.com/questions/30688835/python-daemon-server-crashes-during-html-popup-overlay-callback-using-asyncio-we