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Fixed #26207 -- Replaced dynamic classes with non-data descriptors for deferred instance loading.

This commit is contained in:
Anssi Kääriäinen 2016-02-02 11:33:09 +02:00 committed by Tim Graham
parent dac075e910
commit 7f51876f99
17 changed files with 104 additions and 240 deletions
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5
django/apps/config.py
View File

@ -165,8 +165,7 @@ class AppConfig(object):
raise LookupError(
"App '%s' doesn't have a '%s' model." % (self.label, model_name))
def get_models(self, include_auto_created=False,
include_deferred=False, include_swapped=False):
def get_models(self, include_auto_created=False, include_swapped=False):
"""
Returns an iterable of models.
@ -182,8 +181,6 @@ class AppConfig(object):
"""
self.check_models_ready()
for model in self.models.values():
if model._deferred and not include_deferred:
continue
if model._meta.auto_created and not include_auto_created:
continue
if model._meta.swapped and not include_swapped:

6
django/apps/registry.py
View File

@ -156,8 +156,7 @@ class Apps(object):
# This method is performance-critical at least for Django's test suite.
@lru_cache.lru_cache(maxsize=None)
def get_models(self, include_auto_created=False,
include_deferred=False, include_swapped=False):
def get_models(self, include_auto_created=False, include_swapped=False):
"""
Returns a list of all installed models.
@ -174,8 +173,7 @@ class Apps(object):
result = []
for app_config in self.app_configs.values():
result.extend(list(app_config.get_models(
include_auto_created, include_deferred, include_swapped)))
result.extend(list(app_config.get_models(include_auto_created, include_swapped)))
return result
def get_model(self, app_label, model_name=None):

2
django/contrib/contenttypes/models.py
View File

@ -27,8 +27,6 @@ class ContentTypeManager(models.Manager):
def _get_opts(self, model, for_concrete_model):
if for_concrete_model:
model = model._meta.concrete_model
elif model._deferred:
model = model._meta.proxy_for_model
return model._meta
def _get_from_cache(self, opts):

7
django/contrib/gis/db/models/proxy.py
View File

@ -5,10 +5,11 @@ objects corresponding to geographic model fields.
Thanks to Robert Coup for providing this functionality (see #4322).
"""
from django.db.models.query_utils import DeferredAttribute
from django.utils import six
class SpatialProxy(object):
class SpatialProxy(DeferredAttribute):
def __init__(self, klass, field):
"""
Proxy initializes on the given Geometry or Raster class (not an instance)
@ -16,6 +17,7 @@ class SpatialProxy(object):
"""
self._field = field
self._klass = klass
super(SpatialProxy, self).__init__(field.attname, klass)
def __get__(self, instance, cls=None):
"""
@ -29,7 +31,10 @@ class SpatialProxy(object):
return self
# Getting the value of the field.
try:
geo_value = instance.__dict__[self._field.attname]
except KeyError:
geo_value = super(SpatialProxy, self).__get__(instance, cls)
if isinstance(geo_value, self._klass):
geo_obj = geo_value

3
django/core/serializers/python.py
View File

@ -37,8 +37,7 @@ class Serializer(base.Serializer):
self._current = None
def get_dump_object(self, obj):
model = obj._meta.proxy_for_model if obj._deferred else obj.__class__
data = OrderedDict([('model', force_text(model._meta))])
data = OrderedDict([('model', force_text(obj._meta))])
if not self.use_natural_primary_keys or not hasattr(obj, 'natural_key'):
data["pk"] = force_text(obj._get_pk_val(), strings_only=True)
data['fields'] = self._current

3
django/core/serializers/xml_serializer.py
View File

@ -52,8 +52,7 @@ class Serializer(base.Serializer):
raise base.SerializationError("Non-model object (%s) encountered during serialization" % type(obj))
self.indent(1)
model = obj._meta.proxy_for_model if obj._deferred else obj.__class__
attrs = OrderedDict([("model", smart_text(model._meta))])
attrs = OrderedDict([("model", smart_text(obj._meta))])
if not self.use_natural_primary_keys or not hasattr(obj, 'natural_key'):
obj_pk = obj._get_pk_val()
if obj_pk is not None:

2
django/db/models/__init__.py
View File

@ -19,7 +19,7 @@ from django.db.models.query import ( # NOQA
)
# Imports that would create circular imports if sorted
from django.db.models.base import Model # NOQA isort:skip
from django.db.models.base import DEFERRED, Model # NOQA isort:skip
from django.db.models.fields.related import ( # NOQA isort:skip
ForeignKey, ForeignObject, OneToOneField, ManyToManyField,
ManyToOneRel, ManyToManyRel, OneToOneRel,

86
django/db/models/base.py
View File

@ -27,12 +27,11 @@ from django.db.models.fields.related import (
from django.db.models.manager import ensure_default_manager
from django.db.models.options import Options
from django.db.models.query import Q
from django.db.models.query_utils import (
DeferredAttribute, deferred_class_factory,
)
from django.db.models.utils import make_model_tuple
from django.utils import six
from django.utils.encoding import force_str, force_text
from django.utils.encoding import (
force_str, force_text, python_2_unicode_compatible,
)
from django.utils.functional import curry
from django.utils.six.moves import zip
from django.utils.text import capfirst, get_text_list
@ -40,6 +39,17 @@ from django.utils.translation import ugettext_lazy as _
from django.utils.version import get_version
@python_2_unicode_compatible
class Deferred(object):
def __repr__(self):
return str('<Deferred field>')
def __str__(self):
return str('<Deferred field>')
DEFERRED = Deferred()
def subclass_exception(name, parents, module, attached_to=None):
"""
Create exception subclass. Used by ModelBase below.
@ -353,7 +363,6 @@ class ModelState(object):
class Model(six.with_metaclass(ModelBase)):
_deferred = False
def __init__(self, *args, **kwargs):
signals.pre_init.send(sender=self.__class__, args=args, kwargs=kwargs)
@ -377,11 +386,15 @@ class Model(six.with_metaclass(ModelBase)):
# is *not* consumed. We rely on this, so don't change the order
# without changing the logic.
for val, field in zip(args, fields_iter):
if val is DEFERRED:
continue
setattr(self, field.attname, val)
else:
# Slower, kwargs-ready version.
fields_iter = iter(self._meta.fields)
for val, field in zip(args, fields_iter):
if val is DEFERRED:
continue
setattr(self, field.attname, val)
kwargs.pop(field.name, None)
# Maintain compatibility with existing calls.
@ -393,13 +406,8 @@ class Model(six.with_metaclass(ModelBase)):
for field in fields_iter:
is_related_object = False
# This slightly odd construct is so that we can access any
# data-descriptor object (DeferredAttribute) without triggering its
# __get__ method.
if (field.attname not in kwargs and
(isinstance(self.__class__.__dict__.get(field.attname), DeferredAttribute) or
field.column is None)):
# This field will be populated on request.
# Virtual field
if field.attname not in kwargs and field.column is None:
continue
if kwargs:
if isinstance(field.remote_field, ForeignObjectRel):
@ -435,14 +443,17 @@ class Model(six.with_metaclass(ModelBase)):
# field.name instead of field.attname (e.g. "user" instead of
# "user_id") so that the object gets properly cached (and type
# checked) by the RelatedObjectDescriptor.
if rel_obj is not DEFERRED:
setattr(self, field.name, rel_obj)
else:
if val is not DEFERRED:
setattr(self, field.attname, val)
if kwargs:
for prop in list(kwargs):
try:
if isinstance(getattr(self.__class__, prop), property):
if kwargs[prop] is not DEFERRED:
setattr(self, prop, kwargs[prop])
del kwargs[prop]
except AttributeError:
@ -454,9 +465,10 @@ class Model(six.with_metaclass(ModelBase)):
@classmethod
def from_db(cls, db, field_names, values):
if cls._deferred:
new = cls(**dict(zip(field_names, values)))
else:
if len(values) != len(cls._meta.concrete_fields):
values = list(values)
values.reverse()
values = [values.pop() if f.attname in field_names else DEFERRED for f in cls._meta.concrete_fields]
new = cls(*values)
new._state.adding = False
new._state.db = db
@ -501,17 +513,8 @@ class Model(six.with_metaclass(ModelBase)):
"""
data = self.__dict__
data[DJANGO_VERSION_PICKLE_KEY] = get_version()
if not self._deferred:
class_id = self._meta.app_label, self._meta.object_name
return model_unpickle, (class_id, [], simple_class_factory), data
defers = []
for field in self._meta.fields:
if isinstance(self.__class__.__dict__.get(field.attname),
DeferredAttribute):
defers.append(field.attname)
model = self._meta.proxy_for_model
class_id = model._meta.app_label, model._meta.object_name
return (model_unpickle, (class_id, defers, deferred_class_factory), data)
return model_unpickle, (class_id,), data
def __setstate__(self, state):
msg = None
@ -547,7 +550,7 @@ class Model(six.with_metaclass(ModelBase)):
"""
return {
f.attname for f in self._meta.concrete_fields
if isinstance(self.__class__.__dict__.get(f.attname), DeferredAttribute)
if f.attname not in self.__dict__
}
def refresh_from_db(self, using=None, fields=None, **kwargs):
@ -574,18 +577,14 @@ class Model(six.with_metaclass(ModelBase)):
'are not allowed in fields.' % LOOKUP_SEP)
db = using if using is not None else self._state.db
if self._deferred:
non_deferred_model = self._meta.proxy_for_model
else:
non_deferred_model = self.__class__
db_instance_qs = non_deferred_model._default_manager.using(db).filter(pk=self.pk)
db_instance_qs = self.__class__._default_manager.using(db).filter(pk=self.pk)
# Use provided fields, if not set then reload all non-deferred fields.
deferred_fields = self.get_deferred_fields()
if fields is not None:
fields = list(fields)
db_instance_qs = db_instance_qs.only(*fields)
elif self._deferred:
deferred_fields = self.get_deferred_fields()
elif deferred_fields:
fields = [f.attname for f in self._meta.concrete_fields
if f.attname not in deferred_fields]
db_instance_qs = db_instance_qs.only(*fields)
@ -664,6 +663,7 @@ class Model(six.with_metaclass(ModelBase)):
if force_insert and (force_update or update_fields):
raise ValueError("Cannot force both insert and updating in model saving.")
deferred_fields = self.get_deferred_fields()
if update_fields is not None:
# If update_fields is empty, skip the save. We do also check for
# no-op saves later on for inheritance cases. This bailout is
@ -690,17 +690,11 @@ class Model(six.with_metaclass(ModelBase)):
# If saving to the same database, and this model is deferred, then
# automatically do a "update_fields" save on the loaded fields.
elif not force_insert and self._deferred and using == self._state.db:
elif not force_insert and deferred_fields and using == self._state.db:
field_names = set()
for field in self._meta.concrete_fields:
if not field.primary_key and not hasattr(field, 'through'):
field_names.add(field.attname)
deferred_fields = [
f.attname for f in self._meta.fields
if (f.attname not in self.__dict__ and
isinstance(self.__class__.__dict__[f.attname], DeferredAttribute))
]
loaded_fields = field_names.difference(deferred_fields)
if loaded_fields:
update_fields = frozenset(loaded_fields)
@ -1662,14 +1656,7 @@ def make_foreign_order_accessors(model, related_model):
########
def simple_class_factory(model, attrs):
"""
Needed for dynamic classes.
"""
return model
def model_unpickle(model_id, attrs, factory):
def model_unpickle(model_id):
"""
Used to unpickle Model subclasses with deferred fields.
"""
@ -1678,8 +1665,7 @@ def model_unpickle(model_id, attrs, factory):
else:
# Backwards compat - the model was cached directly in earlier versions.
model = model_id
cls = factory(model, attrs)
return cls.__new__(cls)
return model.__new__(model)
model_unpickle.__safe_for_unpickle__ = True

12
django/db/models/fields/__init__.py
View File

@ -20,7 +20,7 @@ from django.core import checks, exceptions, validators
# purposes.
from django.core.exceptions import FieldDoesNotExist # NOQA
from django.db import connection, connections, router
from django.db.models.query_utils import RegisterLookupMixin
from django.db.models.query_utils import DeferredAttribute, RegisterLookupMixin
from django.utils import six, timezone
from django.utils.datastructures import DictWrapper
from django.utils.dateparse import (
@ -504,10 +504,6 @@ class Field(RegisterLookupMixin):
# class self.__class__, then update its dict with self.__dict__
# values - so, this is very close to normal pickle.
return _empty, (self.__class__,), self.__dict__
if self.model._deferred:
# Deferred model will not be found from the app registry. This
# could be fixed by reconstructing the deferred model on unpickle.
raise RuntimeError("Fields of deferred models can't be reduced")
return _load_field, (self.model._meta.app_label, self.model._meta.object_name,
self.name)
@ -696,6 +692,12 @@ class Field(RegisterLookupMixin):
cls._meta.add_field(self, private=True)
else:
cls._meta.add_field(self)
if self.column:
# Don't override classmethods with the descriptor. This means that
# if you have a classmethod and a field with the same name, then
# such fields can't be deferred (we don't have a check for this).
if not getattr(cls, self.attname, None):
setattr(cls, self.attname, DeferredAttribute(self.attname, cls))
if self.choices:
setattr(cls, 'get_%s_display' % self.name,
curry(cls._get_FIELD_display, field=self))

22
django/db/models/query.py
View File

@ -19,7 +19,7 @@ from django.db.models.deletion import Collector
from django.db.models.expressions import Date, DateTime, F
from django.db.models.fields import AutoField
from django.db.models.query_utils import (
InvalidQuery, Q, check_rel_lookup_compatibility, deferred_class_factory,
InvalidQuery, Q, check_rel_lookup_compatibility,
)
from django.db.models.sql.constants import CURSOR
from django.utils import six, timezone
@ -60,11 +60,6 @@ class ModelIterable(BaseIterable):
model_fields_start, model_fields_end = select_fields[0], select_fields[-1] + 1
init_list = [f[0].target.attname
for f in select[model_fields_start:model_fields_end]]
if len(init_list) != len(model_cls._meta.concrete_fields):
init_set = set(init_list)
skip = [f.attname for f in model_cls._meta.concrete_fields
if f.attname not in init_set]
model_cls = deferred_class_factory(model_cls, skip)
related_populators = get_related_populators(klass_info, select, db)
for row in compiler.results_iter(results):
obj = model_cls.from_db(db, init_list, row[model_fields_start:model_fields_end])
@ -1254,8 +1249,6 @@ class RawQuerySet(object):
if skip:
if self.model._meta.pk.attname in skip:
raise InvalidQuery('Raw query must include the primary key')
model_cls = deferred_class_factory(self.model, skip)
else:
model_cls = self.model
fields = [self.model_fields.get(c) for c in self.columns]
converters = compiler.get_converters([
@ -1718,7 +1711,7 @@ class RelatedPopulator(object):
return [row[row_pos] for row_pos in pos_list]
self.reorder_for_init = reorder_for_init
self.model_cls = self.get_deferred_cls(klass_info, self.init_list)
self.model_cls = klass_info['model']
self.pk_idx = self.init_list.index(self.model_cls._meta.pk.attname)
self.related_populators = get_related_populators(klass_info, select, self.db)
field = klass_info['field']
@ -1732,17 +1725,6 @@ class RelatedPopulator(object):
if field.unique:
self.reverse_cache_name = field.remote_field.get_cache_name()
def get_deferred_cls(self, klass_info, init_list):
model_cls = klass_info['model']
if len(init_list) != len(model_cls._meta.concrete_fields):
init_set = set(init_list)
skip = [
f.attname for f in model_cls._meta.concrete_fields
if f.attname not in init_set
]
model_cls = deferred_class_factory(model_cls, skip)
return model_cls
def populate(self, row, from_obj):
if self.reorder_for_init:
obj_data = self.reorder_for_init(row)

57
django/db/models/query_utils.py
View File

@ -11,7 +11,6 @@ import inspect
from collections import namedtuple
from django.core.exceptions import FieldDoesNotExist
from django.db.backends import utils
from django.db.models.constants import LOOKUP_SEP
from django.utils import tree
@ -97,10 +96,9 @@ class DeferredAttribute(object):
Retrieves and caches the value from the datastore on the first lookup.
Returns the cached value.
"""
non_deferred_model = instance._meta.proxy_for_model
opts = non_deferred_model._meta
assert instance is not None
if instance is None:
return self
opts = instance._meta
data = instance.__dict__
if data.get(self.field_name, self) is self:
# self.field_name is the attname of the field, but only() takes the
@ -119,13 +117,6 @@ class DeferredAttribute(object):
data[self.field_name] = val
return data[self.field_name]
def __set__(self, instance, value):
"""
Deferred loading attributes can be set normally (which means there will
never be a database lookup involved.
"""
instance.__dict__[self.field_name] = value
def _check_parent_chain(self, instance, name):
"""
Check if the field value can be fetched from a parent field already
@ -230,48 +221,6 @@ def select_related_descend(field, restricted, requested, load_fields, reverse=Fa
return True
# This function is needed because data descriptors must be defined on a class
# object, not an instance, to have any effect.
def deferred_class_factory(model, attrs):
"""
Returns a class object that is a copy of "model" with the specified "attrs"
being replaced with DeferredAttribute objects. The "pk_value" ties the
deferred attributes to a particular instance of the model.
"""
if not attrs:
return model
opts = model._meta
# Never create deferred models based on deferred model
if model._deferred:
# Deferred models are proxies for the non-deferred model. We never
# create chains of defers => proxy_for_model is the non-deferred
# model.
model = opts.proxy_for_model
# The app registry wants a unique name for each model, otherwise the new
# class won't be created (we get an exception). Therefore, we generate
# the name using the passed in attrs. It's OK to reuse an existing class
# object if the attrs are identical.
name = "%s_Deferred_%s" % (model.__name__, '_'.join(sorted(attrs)))
name = utils.truncate_name(name, 80, 32)
try:
return opts.apps.get_model(model._meta.app_label, name)
except LookupError:
class Meta:
proxy = True
apps = opts.apps
app_label = opts.app_label
overrides = {attr: DeferredAttribute(attr, model) for attr in attrs}
overrides["Meta"] = Meta
overrides["__module__"] = model.__module__
overrides["_deferred"] = True
return type(str(name), (model,), overrides)
def refs_expression(lookup_parts, annotations):
"""
A helper method to check if the lookup_parts contains references

4
django/views/generic/detail.py
View File

@ -89,8 +89,6 @@ class SingleObjectMixin(ContextMixin):
if self.context_object_name:
return self.context_object_name
elif isinstance(obj, models.Model):
if obj._deferred:
obj = obj._meta.proxy_for_model
return obj._meta.model_name
else:
return None
@ -152,8 +150,6 @@ class SingleObjectTemplateResponseMixin(TemplateResponseMixin):
# only use this if the object in question is a model.
if isinstance(self.object, models.Model):
object_meta = self.object._meta
if self.object._deferred:
object_meta = self.object._meta.proxy_for_model._meta
names.append("%s/%s%s.html" % (
object_meta.app_label,
object_meta.model_name,

37
docs/ref/models/instances.txt
View File

@ -73,13 +73,12 @@ when loading from the database.
The ``db`` argument contains the database alias for the database the model
is loaded from, ``field_names`` contains the names of all loaded fields, and
``values`` contains the loaded values for each field in ``field_names``. The
``field_names`` are in the same order as the ``values``, so it is possible to
use ``cls(**(zip(field_names, values)))`` to instantiate the object. If all
of the model's fields are present, then ``values`` are guaranteed to be in
the order ``__init__()`` expects them. That is, the instance can be created
by ``cls(*values)``. It is possible to check if all fields are present by
consulting ``cls._deferred`` - if ``False``, then all fields have been loaded
from the database.
``field_names`` are in the same order as the ``values``. If all of the model's
fields are present, then ``values`` are guaranteed to be in the order
``__init__()`` expects them. That is, the instance can be created by
``cls(*values)``. If any fields are deferred, they won't appear in
``field_names``. In that case, assign a value of ``django.db.models.DEFERRED``
to each of the missing fields.
In addition to creating the new model, the ``from_db()`` method must set the
``adding`` and ``db`` flags in the new instance's ``_state`` attribute.
@ -87,14 +86,20 @@ In addition to creating the new model, the ``from_db()`` method must set the
Below is an example showing how to record the initial values of fields that
are loaded from the database::
from django.db.models import DEFERRED
@classmethod
def from_db(cls, db, field_names, values):
# default implementation of from_db() (could be replaced
# with super())
if cls._deferred:
instance = cls(**zip(field_names, values))
else:
instance = cls(*values)
# Default implementation of from_db() (subject to change and could
# be replaced with super()).
if len(values) != len(cls._meta.concrete_fields):
values = list(values)
values.reverse()
values = [
values.pop() if f.attname in field_names else DEFERRED
for f in cls._meta.concrete_fields
]
new = cls(*values)
instance._state.adding = False
instance._state.db = db
# customization to store the original field values on the instance
@ -114,6 +119,12 @@ The example above shows a full ``from_db()`` implementation to clarify how that
is done. In this case it would of course be possible to just use ``super()`` call
in the ``from_db()`` method.
.. versionchanged:: 1.10
In older versions, you could check if all fields were loaded by consulting
``cls._deferred``. This attribute is removed and
``django.db.models.DEFERRED`` is new.
Refreshing objects from database
================================

6
docs/releases/1.10.txt
View File

@ -783,6 +783,12 @@ Miscellaneous
Web servers already implement this behavior. Responses retrieved using the
Django test client continue to have these "response fixes" applied.
* ``Model.__init__()`` now receives ``django.db.models.DEFERRED`` as the value
of deferred fields.
* The ``Model._deferred`` attribute is removed as dynamic model classes when
using ``QuerySet.defer()`` and ``only()`` is removed.
.. _deprecated-features-1.10:
Features deprecated in 1.10

4
tests/admin_views/tests.py
View File

@ -3650,7 +3650,7 @@ class AdminCustomQuerysetTest(TestCase):
self.assertContains(
response,
'<li class="success">The short message "<a href="%s">'
'ShortMessage_Deferred_timestamp object</a>" was changed successfully.</li>' %
'ShortMessage object</a>" was changed successfully.</li>' %
reverse('admin:admin_views_shortmessage_change', args=(sm.pk,)), html=True
)
@ -3697,7 +3697,7 @@ class AdminCustomQuerysetTest(TestCase):
self.assertContains(
response,
'<li class="success">The paper "<a href="%s">'
'Paper_Deferred_author object</a>" was changed successfully.</li>' %
'Paper object</a>" was changed successfully.</li>' %
reverse('admin:admin_views_paper_change', args=(p.pk,)), html=True
)

11
tests/defer/tests.py
View File

@ -1,6 +1,6 @@
from __future__ import unicode_literals
from django.db.models.query_utils import DeferredAttribute, InvalidQuery
from django.db.models.query_utils import InvalidQuery
from django.test import TestCase
from .models import (
@ -15,10 +15,7 @@ class AssertionMixin(object):
we examine attribute values. Therefore, this method returns the number
of deferred fields on returned instances.
"""
count = 0
for field in obj._meta.fields:
if isinstance(obj.__class__.__dict__.get(field.attname), DeferredAttribute):
count += 1
count = len(obj.get_deferred_fields())
self.assertEqual(count, num)
@ -45,7 +42,9 @@ class DeferTests(AssertionMixin, TestCase):
# of them except the model's primary key see #15494
self.assert_delayed(qs.only("pk")[0], 3)
# You can use 'pk' with reverse foreign key lookups.
self.assert_delayed(self.s1.primary_set.all().only('pk')[0], 3)
# The related_id is alawys set even if it's not fetched from the DB,
# so pk and related_id are not deferred.
self.assert_delayed(self.s1.primary_set.all().only('pk')[0], 2)
def test_defer_only_chaining(self):
qs = Primary.objects.all()

63
tests/defer_regress/tests.py
View File

@ -2,16 +2,10 @@ from __future__ import unicode_literals
from operator import attrgetter
from django.apps import apps
from django.contrib.contenttypes.models import ContentType
from django.contrib.sessions.backends.db import SessionStore
from django.db import models
from django.db.models import Count
from django.db.models.query_utils import (
DeferredAttribute, deferred_class_factory,
)
from django.test import TestCase, override_settings
from django.test.utils import isolate_apps
from .models import (
Base, Child, Derived, Feature, Item, ItemAndSimpleItem, Leaf, Location,
@ -98,28 +92,6 @@ class DeferRegressionTest(TestCase):
list(SimpleItem.objects.annotate(Count('feature')).only('name')),
list)
def test_ticket_11936(self):
app_config = apps.get_app_config("defer_regress")
# Regression for #11936 - get_models should not return deferred models
# by default. Run a couple of defer queries so that app registry must
# contain some deferred classes. It might contain a lot more classes
# depending on the order the tests are ran.
list(Item.objects.defer("name"))
list(Child.objects.defer("value"))
klasses = {model.__name__ for model in app_config.get_models()}
self.assertIn("Child", klasses)
self.assertIn("Item", klasses)
self.assertNotIn("Child_Deferred_value", klasses)
self.assertNotIn("Item_Deferred_name", klasses)
self.assertFalse(any(k._deferred for k in app_config.get_models()))
klasses_with_deferred = {model.__name__ for model in app_config.get_models(include_deferred=True)}
self.assertIn("Child", klasses_with_deferred)
self.assertIn("Item", klasses_with_deferred)
self.assertIn("Child_Deferred_value", klasses_with_deferred)
self.assertIn("Item_Deferred_name", klasses_with_deferred)
self.assertTrue(any(k._deferred for k in app_config.get_models(include_deferred=True)))
@override_settings(SESSION_SERIALIZER='django.contrib.sessions.serializers.PickleSerializer')
def test_ticket_12163(self):
# Test for #12163 - Pickling error saving session with unsaved model
@ -246,41 +218,6 @@ class DeferRegressionTest(TestCase):
qs = SpecialFeature.objects.only('feature__item__name').select_related('feature__item')
self.assertEqual(len(qs), 1)
def test_deferred_class_factory(self):
new_class = deferred_class_factory(
Item,
('this_is_some_very_long_attribute_name_so_modelname_truncation_is_triggered',))
self.assertEqual(
new_class.__name__,
'Item_Deferred_this_is_some_very_long_attribute_nac34b1f495507dad6b02e2cb235c875e')
def test_deferred_class_factory_already_deferred(self):
deferred_item1 = deferred_class_factory(Item, ('name',))
deferred_item2 = deferred_class_factory(deferred_item1, ('value',))
self.assertIs(deferred_item2._meta.proxy_for_model, Item)
self.assertNotIsInstance(deferred_item2.__dict__.get('name'), DeferredAttribute)
self.assertIsInstance(deferred_item2.__dict__.get('value'), DeferredAttribute)
def test_deferred_class_factory_no_attrs(self):
deferred_cls = deferred_class_factory(Item, ())
self.assertFalse(deferred_cls._deferred)
@isolate_apps('defer_regress', kwarg_name='apps')
def test_deferred_class_factory_apps_reuse(self, apps):
"""
#25563 - model._meta.apps should be used for caching and
retrieval of the created proxy class.
"""
class BaseModel(models.Model):
field = models.BooleanField()
class Meta:
app_label = 'defer_regress'
deferred_model = deferred_class_factory(BaseModel, ['field'])
self.assertIs(deferred_model._meta.apps, apps)
self.assertIs(deferred_class_factory(BaseModel, ['field']), deferred_model)
class DeferAnnotateSelectRelatedTest(TestCase):
def test_defer_annotate_select_related(self):