Mercurial > public > sg101
annotate weblinks/signals.py @ 629:f4c043cf55ac
Wiki integration. Requests don't always have sessions.
In particular this occurs when a request is made without a trailing slash.
The Common middleware redirects when this happens, and the middleware
process_request() processing stops before a session can get added.
So just set an attribute on the request object for each operation.
This seemed weird to me at first, but there are plenty of examples of this
in the Django code base already.
| author | Brian Neal <bgneal@gmail.com> |
|---|---|
| date | Tue, 13 Nov 2012 13:50:06 -0600 |
| parents | ee87ea74d46b |
| children |
| rev | line source |
|---|---|
| bgneal@202 | 1 """Signals for the weblinks application. |
| bgneal@202 | 2 We use signals to compute the denormalized category counts whenever a weblink |
| bgneal@202 | 3 is saved.""" |
| bgneal@202 | 4 from django.db.models.signals import post_save |
| bgneal@202 | 5 from django.db.models.signals import post_delete |
| bgneal@202 | 6 |
| bgneal@202 | 7 from weblinks.models import Category, Link |
| bgneal@202 | 8 |
| bgneal@202 | 9 |
| bgneal@202 | 10 def on_link_save(sender, **kwargs): |
| bgneal@202 | 11 """This function updates the count field for all categories. |
| bgneal@202 | 12 It is called whenever a link is saved via a signal. |
| bgneal@202 | 13 """ |
| bgneal@202 | 14 if kwargs['created']: |
| bgneal@202 | 15 # we only have to update the parent category |
| bgneal@202 | 16 link = kwargs['instance'] |
| bgneal@202 | 17 cat = link.category |
| bgneal@202 | 18 cat.count = Link.public_objects.filter(category=cat).count() |
| bgneal@202 | 19 cat.save() |
| bgneal@202 | 20 else: |
| bgneal@202 | 21 # update all categories just to be safe (an existing link could |
| bgneal@202 | 22 # have been moved from one category to another |
| bgneal@202 | 23 cats = Category.objects.all() |
| bgneal@202 | 24 for cat in cats: |
| bgneal@202 | 25 cat.count = Link.public_objects.filter(category=cat).count() |
| bgneal@202 | 26 cat.save() |
| bgneal@202 | 27 |
| bgneal@202 | 28 |
| bgneal@202 | 29 def on_link_delete(sender, **kwargs): |
| bgneal@202 | 30 """This function updates the count field for the link's parent |
| bgneal@202 | 31 category. It is called when a link is deleted via a signal. |
| bgneal@202 | 32 """ |
| bgneal@202 | 33 # update the parent category |
| bgneal@202 | 34 link = kwargs['instance'] |
| bgneal@202 | 35 cat = link.category |
| bgneal@202 | 36 cat.count = Link.public_objects.filter(category=cat).count() |
| bgneal@202 | 37 cat.save() |
| bgneal@202 | 38 |
| bgneal@202 | 39 |
| bgneal@260 | 40 post_save.connect(on_link_save, sender=Link, dispatch_uid='weblinks.signals') |
| bgneal@260 | 41 post_delete.connect(on_link_delete, sender=Link, dispatch_uid='weblinks.signals') |