On Thu, 2012-03-29 at 07:18 -0400, Jim Fulton wrote:
> On Wed, Mar 28, 2012 at 6:37 PM, Chris McDonough <chr...@plope.com> wrote:
> > On Wed, 2012-03-28 at 17:06 -0400, Jim Fulton wrote:
> >> On Wed, Mar 28, 2012 at 4:37 PM, Chris McDonough <chr...@plope.com> wrote:
> >> > On Wed, 2012-03-28 at 14:21 -0400, Jim Fulton wrote:
> >> ...
> >> > A decorator for running some code in the context of a txn and retrying
> >> > retryable exceptions would be nice higher level behavior. Â I'd be
> >> > willing to do this work over this weekend.
> >> Cool. Don't forget the transaction note part. :)
> >> Too many transactions in our apps don't have
> >> notes, especially transactions that happen
> >> outside of web requests.
> >> > In the meantime, I think the existing attempts context manager still
> >> > needs the small fix I proposed in my original message. Â Can you confirm
> >> > that my understanding of the its intent seems roughly correct?
> >> I didn't see a statement of intent. I think your fix us good,
> >> but the code (that I wrote and your fix) makes my head hurt. :)
> >> I'd say, make some test cases for the bug and make it pass.
> > OK. Once I fix this "Attempts" bug, I think the decorator code is just
> > a higher level interface that uses it:
> > class job(object):
> > def __init__(self, attempts=1, note=None, manager=None):
> > self.attempts = attempts
> > self.note = note
> > if manager is None:
> > manager = transaction.manager
> > self.manager = manager
> > def __call__(self, wrapped):
> > note = self.note
> > if note is None:
> > note = getattr(wrapped, '__name__', None)
> > def inner(*arg, **kw):
> > for attempt in self.manager.attempts(self.attempts):
> > with attempt as t:
> > t.note(note)
> > return wrapped(*arg, **kw)
> > .. or something like that...
> It could be written that way, although I would
> use a much simpler implementation.
> The attempt design was a reach to overcome
> the limitations of the with statement. I'm not at all happy
> with it, although I couldn't think of anything better at the
> time. I hate to build on it.
It's brainbusting, yes, but it works. Do you have any other specific
pattern in mind?
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