def get_prefetch_query_set(self, instances):
db = self._db or router.db_for_read(self.model, instance=instances[0])
query = {
'%s__pk' % self.content_type_field_name: self.content_type.id,
'%s__in' % self.object_id_field_name:
set(obj._get_pk_val() for obj in instances)
}
qs = super(GenericRelatedObjectManager, self).get_query_set().using(db).filter(**query)
return (qs,
attrgetter(self.object_id_field_name),
lambda obj: obj._get_pk_val(),
False,
self.prefetch_cache_name)
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
table = connections[db].ops.quote_name(self._table)
cursor = connections[db].cursor()
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connections[db].ops.value_to_db_datetime(now)])
return cursor.fetchone() is not None
def get(self, key, default=None, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
table = connections[db].ops.quote_name(self._table)
cursor = connections[db].cursor()
cursor.execute("SELECT cache_key, value, expires FROM %s "
"WHERE cache_key = %%s" % table, [key])
row = cursor.fetchone()
if row is None:
return default
now = timezone.now()
if row[2] < now:
db = router.db_for_write(self.cache_model_class)
cursor = connections[db].cursor()
cursor.execute("DELETE FROM %s "
"WHERE cache_key = %%s" % table, [key])
transaction.commit_unless_managed(using=db)
return default
value = connections[db].ops.process_clob(row[1])
return pickle.loads(base64.b64decode(force_bytes(value)))
def get_query_set(self):
try:
return self.instance._prefetched_objects_cache[self.prefetch_cache_name]
except (AttributeError, KeyError):
db = self._db or router.db_for_read(self.model, instance=self.instance)
return super(GenericRelatedObjectManager, self).get_query_set().using(db).filter(**self.core_filters)
def db(self):
return self._db or router.db_for_read(self.model)
