On 01:48 pm, chris@simplistix.co.uk wrote:
Hi All,
The attached .py file demonstrates a problem I'm having with a little scheduler I need to maintain.
The loop() function is supposed to be a "catch all and report" error handler. However, when the async code initiated by doStuff throws the AttributeError, what actually gets logged is:
2010-09-28 14:41:15,706 ERROR : log (14757|7f691ba676e0): Unhandled Error File "test_looping.py", line 24, in __call__ del self.connector exceptions.AttributeError: Break instance has no attribute 'connector'
2010-09-28 14:41:15,707 ERROR : log (14757|7f691ba676e0): Unhandled scheduled exception File "test_looping.py", line 35, in loop yield doStuff() exceptions.GeneratorExit:
But, more crucially, the looping call then appears to stop.
The function you're looping over returns a Deferred that never fires. The LoopingCall isn't stopped, it's waiting for the Deferred.
What can I do to get the exception logged and then everything handled sanely such that the looping call can continue and my lopp function will keep getting called once every second rather than stopping?
When you do reactor.callLater(n, f), you put f into an execution context where the only thing that will happen to exceptions it raises is that they will be logged. If you want something else to happen to the exception, then you have to arrange for that. You can do this by wrapping f with another function that handles the exception and sends it where you want. Or you can use twisted.internet.task.deferLater, which probably does something pretty close to what you want. Jean-Paul