django-generic-aggregation provides annotate() and aggregate() for generically-related data.
Examples
You want the most commented on blog entries:
>>> from django.contrib.comments.models import Comment
>>> from django.db.models import Count
>>> from blog.models import BlogEntry
>>> from generic_aggregation import generic_annotate
>>> annotated = generic_annotate(BlogEntry.objects.all(), Comment.content_object, 'id', Count)
>>> for entry in annotated:
... print entry.title, entry.score
The most popular 5
The second best 4
Nobody commented 0
You want to figure out which items are highest rated:
from django.db.models import Sum, Avg
# assume a Food model and a generic Rating model
apple = Food.objects.create(name='apple')
# create some ratings on the food
Rating.objects.create(content_object=apple, rating=3)
Rating.objects.create(content_object=apple, rating=5)
Rating.objects.create(content_object=apple, rating=7)
>>> aggregate = generic_aggregate(Food.objects.all(), Rating.content_object, 'rating', Sum)
>>> print aggregate
15
>>> aggregate = generic_aggregate(Food.objects.all(), Rating.content_object, 'rating', Avg)
>>> print aggregate
5
Check the tests - there are more examples there. Tested with postgres & sqlite
Product's homepage
Requirements:
· Python
· Django