evennia/lib/utils/idmapper/manager.py

44 lines
1.6 KiB
Python
Executable file

from django.db.models.manager import Manager
try:
from django.db import router
except:
pass
class SharedMemoryManager(Manager):
# CL: this ensures our manager is used when accessing instances via
# ForeignKey etc. (see docs)
use_for_related_fields = True
# CL: in the dev version of django, ReverseSingleRelatedObjectDescriptor
# will call us as:
# rel_obj = rel_mgr.using(db).get(**params)
# We need to handle using, or the get method will be called on a vanilla
# queryset, and we won't get a change to use the cache.
#TODO - removing this for django1.7 - the call mentioned above doesn't happen
# anymore but is the cache still used? /Griatch
#def using(self, alias):
# if alias == router.db_for_read(self.model):
# # this should return a queryset!
# return self
# else:
# return super(SharedMemoryManager, self).using(alias)
# TODO: improve on this implementation
# We need a way to handle reverse lookups so that this model can
# still use the singleton cache, but the active model isn't required
# to be a SharedMemoryModel.
def get(self, **kwargs):
items = kwargs.keys()
inst = None
if len(items) == 1:
# CL: support __exact
key = items[0]
if key.endswith('__exact'):
key = key[:-len('__exact')]
if key in ('pk', self.model._meta.pk.attname):
inst = self.model.get_cached_instance(kwargs[items[0]])
if inst is None:
inst = super(SharedMemoryManager, self).get(**kwargs)
return inst