Cleanups to related manager code, especially in use of closures.

The related manager classes are defined within functions, and the methods
had inconsistent and confusing usage of closures vs. parameters on self to
retrieve needed information. Everything is stored on self now.

Also some methods were not using super() where they should have been.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16913 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Luke Plant 2011-09-29 15:30:29 +00:00
parent e3a6ac8f60
commit 6d6fe61bf6
2 changed files with 37 additions and 33 deletions

View File

@ -266,7 +266,7 @@ def create_generic_related_manager(superclass):
'%s__pk' % self.content_type_field_name : self.content_type.id,
'%s__exact' % self.object_id_field_name : self.pk_val,
}
return superclass.get_query_set(self).using(db).filter(**query)
return super(GenericRelatedObjectManager, self).get_query_set().using(db).filter(**query)
def add(self, *objs):
for obj in objs:

View File

@ -414,88 +414,90 @@ class ForeignRelatedObjectsDescriptor(object):
Creates the managers used by other methods (__get__() and delete()).
"""
rel_field = self.related.field
rel_model = self.related.model
class RelatedManager(superclass):
def __init__(self, model=None, core_filters=None, instance=None):
def __init__(self, model=None, core_filters=None, instance=None,
rel_field=None):
super(RelatedManager, self).__init__()
self.model = model
self.core_filters = core_filters
self.instance = instance
self.rel_field = rel_field
def get_query_set(self):
db = self._db or router.db_for_read(rel_model, instance=self.instance)
return superclass.get_query_set(self).using(db).filter(**(self.core_filters))
db = self._db or router.db_for_read(self.model, instance=self.instance)
return super(RelatedManager, self).get_query_set().using(db).filter(**(self.core_filters))
def add(self, *objs):
for obj in objs:
if not isinstance(obj, self.model):
raise TypeError("'%s' instance expected" % self.model._meta.object_name)
setattr(obj, rel_field.name, self.instance)
setattr(obj, self.rel_field.name, self.instance)
obj.save()
add.alters_data = True
def create(self, **kwargs):
kwargs[rel_field.name] = self.instance
db = router.db_for_write(rel_model, instance=self.instance)
kwargs[self.rel_field.name] = self.instance
db = router.db_for_write(self.model, instance=self.instance)
return super(RelatedManager, self.db_manager(db)).create(**kwargs)
create.alters_data = True
def get_or_create(self, **kwargs):
# Update kwargs with the related object that this
# ForeignRelatedObjectsDescriptor knows about.
kwargs[rel_field.name] = self.instance
db = router.db_for_write(rel_model, instance=self.instance)
kwargs[self.rel_field.name] = self.instance
db = router.db_for_write(self.model, instance=self.instance)
return super(RelatedManager, self.db_manager(db)).get_or_create(**kwargs)
get_or_create.alters_data = True
# remove() and clear() are only provided if the ForeignKey can have a value of null.
if rel_field.null:
def remove(self, *objs):
val = getattr(self.instance, rel_field.rel.get_related_field().attname)
val = getattr(self.instance, self.rel_field.rel.get_related_field().attname)
for obj in objs:
# Is obj actually part of this descriptor set?
if getattr(obj, rel_field.attname) == val:
setattr(obj, rel_field.name, None)
if getattr(obj, self.rel_field.attname) == val:
setattr(obj, self.rel_field.name, None)
obj.save()
else:
raise rel_field.rel.to.DoesNotExist("%r is not related to %r." % (obj, self.instance))
raise self.rel_field.rel.to.DoesNotExist("%r is not related to %r." % (obj, self.instance))
remove.alters_data = True
def clear(self):
self.update(**{rel_field.name: None})
self.update(**{self.rel_field.name: None})
clear.alters_data = True
attname = rel_field.rel.get_related_field().name
return RelatedManager(model=self.related.model,
core_filters = {'%s__%s' % (rel_field.name, attname):
getattr(instance, attname)},
instance=instance
instance=instance,
rel_field=rel_field,
)
def create_many_related_manager(superclass, rel):
"""Creates a manager that subclasses 'superclass' (which is a Manager)
and adds behavior for many-to-many related objects."""
through = rel.through
class ManyRelatedManager(superclass):
def __init__(self, model=None, core_filters=None, instance=None, symmetrical=None,
source_field_name=None, target_field_name=None, reverse=False):
source_field_name=None, target_field_name=None, reverse=False,
through=None):
super(ManyRelatedManager, self).__init__()
self.core_filters = core_filters
self.model = model
self.symmetrical = symmetrical
self.core_filters = core_filters
self.instance = instance
self.symmetrical = symmetrical
self.source_field_name = source_field_name
self.target_field_name = target_field_name
self.reverse = reverse
self.through = through
self._pk_val = self.instance.pk
self.reverse = reverse
if self._pk_val is None:
raise ValueError("%r instance needs to have a primary key value before a many-to-many relationship can be used." % instance.__class__.__name__)
def get_query_set(self):
db = self._db or router.db_for_read(self.instance.__class__, instance=self.instance)
return superclass.get_query_set(self).using(db)._next_is_sticky().filter(**(self.core_filters))
return super(ManyRelatedManager, self).get_query_set().using(db)._next_is_sticky().filter(**(self.core_filters))
# If the ManyToMany relation has an intermediary model,
# the add and remove methods do not exist.
@ -527,8 +529,8 @@ def create_many_related_manager(superclass, rel):
def create(self, **kwargs):
# This check needs to be done here, since we can't later remove this
# from the method lookup table, as we do with add and remove.
if not rel.through._meta.auto_created:
opts = through._meta
if not self.through._meta.auto_created:
opts = self.through._meta
raise AttributeError("Cannot use create() on a ManyToManyField which specifies an intermediary model. Use %s.%s's Manager instead." % (opts.app_label, opts.object_name))
db = router.db_for_write(self.instance.__class__, instance=self.instance)
new_obj = super(ManyRelatedManager, self.db_manager(db)).create(**kwargs)
@ -577,7 +579,7 @@ def create_many_related_manager(superclass, rel):
if self.reverse or source_field_name == self.source_field_name:
# Don't send the signal when we are inserting the
# duplicate data row for symmetrical reverse entries.
signals.m2m_changed.send(sender=rel.through, action='pre_add',
signals.m2m_changed.send(sender=self.through, action='pre_add',
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=new_ids, using=db)
# Add the ones that aren't there already
@ -591,7 +593,7 @@ def create_many_related_manager(superclass, rel):
if self.reverse or source_field_name == self.source_field_name:
# Don't send the signal when we are inserting the
# duplicate data row for symmetrical reverse entries.
signals.m2m_changed.send(sender=rel.through, action='post_add',
signals.m2m_changed.send(sender=self.through, action='post_add',
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=new_ids, using=db)
@ -615,7 +617,7 @@ def create_many_related_manager(superclass, rel):
if self.reverse or source_field_name == self.source_field_name:
# Don't send the signal when we are deleting the
# duplicate data row for symmetrical reverse entries.
signals.m2m_changed.send(sender=rel.through, action="pre_remove",
signals.m2m_changed.send(sender=self.through, action="pre_remove",
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=old_ids, using=db)
# Remove the specified objects from the join table
@ -626,7 +628,7 @@ def create_many_related_manager(superclass, rel):
if self.reverse or source_field_name == self.source_field_name:
# Don't send the signal when we are deleting the
# duplicate data row for symmetrical reverse entries.
signals.m2m_changed.send(sender=rel.through, action="post_remove",
signals.m2m_changed.send(sender=self.through, action="post_remove",
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=old_ids, using=db)
@ -636,7 +638,7 @@ def create_many_related_manager(superclass, rel):
if self.reverse or source_field_name == self.source_field_name:
# Don't send the signal when we are clearing the
# duplicate data rows for symmetrical reverse entries.
signals.m2m_changed.send(sender=rel.through, action="pre_clear",
signals.m2m_changed.send(sender=self.through, action="pre_clear",
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=None, using=db)
self.through._default_manager.using(db).filter(**{
@ -645,7 +647,7 @@ def create_many_related_manager(superclass, rel):
if self.reverse or source_field_name == self.source_field_name:
# Don't send the signal when we are clearing the
# duplicate data rows for symmetrical reverse entries.
signals.m2m_changed.send(sender=rel.through, action="post_clear",
signals.m2m_changed.send(sender=self.through, action="post_clear",
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=None, using=db)
@ -678,7 +680,8 @@ class ManyRelatedObjectsDescriptor(object):
symmetrical=False,
source_field_name=self.related.field.m2m_reverse_field_name(),
target_field_name=self.related.field.m2m_field_name(),
reverse=True
reverse=True,
through=self.related.field.rel.through,
)
return manager
@ -730,7 +733,8 @@ class ReverseManyRelatedObjectsDescriptor(object):
symmetrical=self.field.rel.symmetrical,
source_field_name=self.field.m2m_field_name(),
target_field_name=self.field.m2m_reverse_field_name(),
reverse=False
reverse=False,
through=self.field.rel.through,
)
return manager