def get(self, *args, **kwargs):
"""
Checks the cache to see if there's a cached entry for this pk. If not, fetches
using super then stores the result in cache.
Most of the logic here was gathered from a careful reading of
``django.db.models.sql.query.add_filter``
"""
if self.query.where:
# If there is any other ``where`` filter on this QuerySet just call
# super. There will be a where clause if this QuerySet has already
# been filtered/cloned.
return super(CachingQuerySet, self).get(*args, **kwargs)
# Punt on anything more complicated than get by pk/id only...
if len(kwargs) == 1:
k = kwargs.keys()[0]
if k in ('pk', 'pk__exact', '%s' % self.model._meta.pk.attname,
'%s__exact' % self.model._meta.pk.attname):
obj = cache.get(self.model._cache_key(pk=kwargs.values()[0]))
if obj is not None:
obj.from_cache = True
return obj
obj = super(CachingQuerySet, self).get(*args, **kwargs)
cache.set(obj.cache_key,obj)
return obj
def all(self):
key = instance._get_cache_key(field=field_name)
qs = super(CachingRelatedManager, self).get_query_set()
PKListQuerySet = get_pk_list_query_set(qs.__class__)
qs = qs._clone(klass=PKListQuerySet)
pk_list = cache.get(key)
if pk_list is None:
pk_list = qs.values_list('pk', flat=True)
cache.add(key, list(pk_list), CACHE_DURATION)
else:
qs.from_cache = True
qs.pk_list = pk_list
return qs
