def contribute_to_class(self, cls, name):
# To support multiple relations to self, it's useful to have a non-None
# related name on symmetrical relations for internal reasons. The
# concept doesn't make a lot of sense externally ("you want me to
# specify *what* on my non-reversible relation?!"), so we set it up
# automatically. The funky name reduces the chance of an accidental
# clash.
if self.rel.symmetrical and (self.rel.to == "self" or self.rel.to == cls._meta.object_name):
self.rel.related_name = "%s_rel_+" % name
super(ManyToManyField, self).contribute_to_class(cls, name)
# The intermediate m2m model is not auto created if:
# 1) There is a manually specified intermediate, or
# 2) The class owning the m2m field is abstract.
# 3) The class owning the m2m field has been swapped out.
if not self.rel.through and not cls._meta.abstract and not getattr(cls._meta, 'swapped', False):
self.rel.through = create_many_to_many_intermediary_model(self, cls)
# Add the descriptor for the m2m relation
setattr(cls, self.name, ReverseManyRelatedObjectsDescriptor(self))
# Set up the accessor for the m2m table name for the relation
self.m2m_db_table = curry(self._get_m2m_db_table, cls._meta)
# Populate some necessary rel arguments so that cross-app relations
# work correctly.
if isinstance(self.rel.through, six.string_types):
def resolve_through_model(field, model, cls):
field.rel.through = model
add_lazy_relation(cls, self, self.rel.through, resolve_through_model)
def get_intermediate_model_meta_class(self, klass, from_field_name,
to_field_name,
sort_value_field_name):
managed = True
to_model = self.rel.to
if isinstance(self.rel.to, six.string_types):
if self.rel.to != RECURSIVE_RELATIONSHIP_CONSTANT:
def set_managed(field, model, cls):
field.rel.through._meta.managed = model._meta.managed or cls._meta.managed
add_lazy_relation(klass, self, to_model, set_managed)
else:
managed = klass._meta.managed
else:
managed = klass._meta.managed or to_model._meta.managed
options = {
'db_table': self._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'db_tablespace': klass._meta.db_tablespace,
'unique_together': ((from_field_name, to_field_name),),
'ordering': (sort_value_field_name,),
'verbose_name': '%(from)s-%(to)s relationship' % {'from': from_field_name, 'to': to_field_name},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {'from': from_field_name, 'to': to_field_name},
}
# Django 1.6 support.
if hasattr(self.model._meta, 'apps'):
options.update({
'apps': self.model._meta.apps,
})
return type(str('Meta'), (object,), options)
def contribute_to_class(self, cls, name):
if VERSION < (1, 7):
self.name = self.column = self.attname = name
else:
self.set_attributes_from_name(name)
self.model = cls
cls._meta.add_field(self)
setattr(cls, name, self)
if not cls._meta.abstract:
if isinstance(self.rel.to, six.string_types):
def resolve_related_class(field, model, cls):
field.rel.to = model
add_lazy_relation(cls, self, self.rel.to,
resolve_related_class)
if isinstance(self.through, six.string_types):
def resolve_related_class(field, model, cls):
self.through = model
self.rel.through = model
self.post_through_setup(cls)
add_lazy_relation(cls, self, self.through,
resolve_related_class)
else:
self.post_through_setup(cls)
def contribute_to_class(self, cls, name):
if VERSION < (1, 7):
self.name = self.column = self.attname = name
else:
self.set_attributes_from_name(name)
self.model = cls
cls._meta.add_field(self)
setattr(cls, name, self)
if not cls._meta.abstract:
if isinstance(self.rel.to, six.string_types):
def resolve_related_class(field, model, cls):
field.rel.to = model
add_lazy_relation(cls, self, self.rel.to, resolve_related_class)
if isinstance(self.through, six.string_types):
def resolve_related_class(field, model, cls):
self.through = model
self.rel.through = model
self.post_through_setup(cls)
add_lazy_relation(cls, self, self.through, resolve_related_class)
else:
self.post_through_setup(cls)
def contribute_to_class(self, source, name):
if not issubclass(source, NodeModel):
raise TypeError("Relationships may only extend from Nodes.")
self.creation_counter = source.creation_counter
# make sure this relationship doesn't overlap with another of the same
# type and direction
if hasattr(source._meta, '_relationships'):
for r in source._meta._relationships.values():
if r.rel_type == self.name and r.direction == self.direction:
import warnings
warnings.warn('`%s` and `%s` share a relationship type and '
'direction. Is this what you meant to do?'
% (r.name, name))
bound = self._get_new_bound_relationship(source, name)
source._meta.add_field(bound)
if not hasattr(source._meta, '_relationships'):
source._meta._relationships = {}
source._meta._relationships[name] = bound
setattr(source, name, bound)
if isinstance(self.__target, basestring):
def setup(field, target, source):
if not issubclass(target, NodeModel):
raise TypeError("Relationships may only extend from Nodes.")
# replace the string target with the real target
self.__target = target
bound._setup_reversed(target)
add_lazy_relation(source, self, self.__target, setup)
target = self.__target
if not self.__is_reversed:
bound._setup_reversed(target)
def contribute_to_class(self, cls, name):
self.name = self.column = self.attname = name
if self.column:
self.concrete = True
self.model = cls
# Put together permission codename using the models name
self.codename = "%s_%s" % (
self.permission,
self.model._meta.object_name.lower()
)
cls._meta.add_field(self)
setattr(cls, name, self)
# Store the opts for related_query_name()
self.opts = cls._meta
if not cls._meta.abstract:
if isinstance(self.through, basestring):
def resolve_related_class(field, model, cls):
self.through = model
self.post_through_setup(cls)
add_lazy_relation(
cls, self, self.through, resolve_related_class
)
else:
self.post_through_setup(cls)
def contribute_to_class(self, cls, name, virtual_only=False):
# We need to skip RelatedField in the mro, so we can't use `super()`
Field.contribute_to_class(
self, cls, name, virtual_only=virtual_only
)
self.opts = cls._meta
if not cls._meta.abstract and self.rel.related_name:
related_name = force_text(self.rel.related_name) % {
'class': cls.__name__.lower(),
'app_label': cls._meta.app_label.lower()
}
self.rel.related_name = related_name
for state in system_layout.allowed_values:
with system_layout.as_value(state):
other = self.to
if other is None:
# This should only happen if `cls` is not going to be
# used for `state`. Just leave the null value there
continue
if isinstance(other, str) or other._meta.pk is None:
def resolve_related_class(field, model, cls, state=state):
with system_layout.as_value(state):
field.to = model
field.do_related_class(model, cls)
add_lazy_relation(cls, self, other, resolve_related_class)
else:
self.do_related_class(other, cls)
def contribute_to_class(self, cls, name, virtual_only=False):
# We need to skip RelatedField in the mro, so we can't use `super()`
Field.contribute_to_class(self, cls, name, virtual_only=virtual_only)
self.opts = cls._meta
if not cls._meta.abstract and self.rel.related_name:
related_name = force_text(self.rel.related_name) % {
'class': cls.__name__.lower(),
'app_label': cls._meta.app_label.lower()
}
self.rel.related_name = related_name
for state in system_layout.allowed_values:
with system_layout.as_value(state):
other = self.to
if other is None:
# This should only happen if `cls` is not going to be
# used for `state`. Just leave the null value there
continue
if isinstance(other, str) or other._meta.pk is None:
def resolve_related_class(field, model, cls, state=state):
with system_layout.as_value(state):
field.to = model
field.do_related_class(model, cls)
add_lazy_relation(cls, self, other, resolve_related_class)
else:
self.do_related_class(other, cls)
def _prepare(cls):
"""
Creates some methods once self._meta has been populated.
"""
opts = cls._meta
opts._prepare(cls)
if opts.order_with_respect_to:
cls.get_next_in_order = curry(cls._get_next_or_previous_in_order, is_next=True)
cls.get_previous_in_order = curry(cls._get_next_or_previous_in_order, is_next=False)
# defer creating accessors on the foreign class until we are
# certain it has been created
def make_foreign_order_accessors(field, model, cls):
setattr(field.rel.to, "get_%s_order" % cls.__name__.lower(), curry(method_get_order, cls))
setattr(field.rel.to, "set_%s_order" % cls.__name__.lower(), curry(method_set_order, cls))
add_lazy_relation(
cls, opts.order_with_respect_to, opts.order_with_respect_to.rel.to, make_foreign_order_accessors
)
# Give the class a docstring -- its definition.
if cls.__doc__ is None:
cls.__doc__ = "%s(%s)" % (cls.__name__, ", ".join(f.attname for f in opts.fields))
if hasattr(cls, "get_absolute_url"):
cls.get_absolute_url = update_wrapper(
curry(get_absolute_url, opts, cls.get_absolute_url), cls.get_absolute_url
)
signals.class_prepared.send(sender=cls)
def setup_versioned_models(sender, **kargs):
from versions.models import VersionsModel
if issubclass(sender, VersionsModel):
# Register this model with the version registry.
qn = connection.ops.quote_name
_versions_table_mappings[qn(sender._meta.db_table)] = sender
try:
name_map = sender._meta._name_map
except AttributeError:
name_map = sender._meta.init_name_map()
for name, data in name_map.items():
field = data[0]
if isinstance(field, (related.ForeignKey, related.ManyToManyField)):
if isinstance(field, related.ForeignKey):
setattr(sender, name, VersionsReverseSingleRelatedObjectDescriptor(field))
else:
setattr(sender, name, VersionsReverseManyRelatedObjectsDescriptor(field))
if isinstance(field.rel.to, basestring):
def resolve_related_class(field, model, cls):
field.rel.to = model
field.do_related_class(model, cls)
setattr(field.rel.to, field.related.get_accessor_name(), VersionsForeignRelatedObjectsDescriptor(field.related))
related.add_lazy_relation(sender, field, field.rel.to, resolve_related_class)
else:
setattr(field.rel.to, field.related.get_accessor_name(), VersionsForeignRelatedObjectsDescriptor(field.related))
# Clean up after ourselves so that no previously initialized field caches are invalid.
for cache_name in ('_related_many_to_many_cache', '_name_map', '_related_objects_cache', '_m2m_cache', '_field_cache',):
try:
delattr(sender._meta, cache_name)
except:
pass
def contribute_to_class(self, source, name):
if not issubclass(source, NodeModel):
raise TypeError("Relationships may only extend from Nodes.")
self.creation_counter = source.creation_counter
# make sure this relationship doesn't overlap with another of the same
# type and direction
if hasattr(source._meta, '_relationships'):
for r in source._meta._relationships.values():
if r.rel_type == self.name and r.direction == self.direction:
import warnings
warnings.warn(
'`%s` and `%s` share a relationship type and '
'direction. Is this what you meant to do?' %
(r.name, name))
bound = self._get_new_bound_relationship(source, name)
source._meta.add_field(bound)
if not hasattr(source._meta, '_relationships'):
source._meta._relationships = {}
source._meta._relationships[name] = bound
setattr(source, name, bound)
if isinstance(self.__target, basestring):
def setup(field, target, source):
if not issubclass(target, NodeModel):
raise TypeError(
"Relationships may only extend from Nodes.")
# replace the string target with the real target
self.__target = target
bound._setup_reversed(target)
add_lazy_relation(source, self, self.__target, setup)
target = self.__target
if not self.__is_reversed:
bound._setup_reversed(target)
def get_intermediate_model_meta_class(self, klass, from_field_name,
to_field_name,
sort_value_field_name):
managed = True
to_model = self.rel.to
if isinstance(self.rel.to, six.string_types):
if self.rel.to != RECURSIVE_RELATIONSHIP_CONSTANT:
def set_managed(field, model, cls):
field.rel.through._meta.managed = model._meta.managed or cls._meta.managed
add_lazy_relation(klass, self, to_model, set_managed)
else:
managed = klass._meta.managed
else:
managed = klass._meta.managed or to_model._meta.managed
options = {
'db_table': self._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'db_tablespace': klass._meta.db_tablespace,
'unique_together': ((from_field_name, to_field_name),),
'ordering': (sort_value_field_name,),
'verbose_name': '%(from)s-%(to)s relationship' % {'from': from_field_name, 'to': to_field_name},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {'from': from_field_name, 'to': to_field_name},
}
# Django 1.6 support.
if hasattr(self.model._meta, 'apps'):
options.update({
'apps': self.model._meta.apps,
})
return type(str('Meta'), (object,), options)
def create_one_to_many_intermediary_model(field, klass):
"""
Identical to the 'create_many_to_many_intermediary_model' implementation
from django.db.models.fields.related, but with a 'unique' constraint added
to the receiving relation.
"""
from django.db import models
managed = True
if isinstance(
field.rel.to,
basestring) and field.rel.to != RECURSIVE_RELATIONSHIP_CONSTANT:
to_model = field.rel.to
to = to_model.split('.')[-1]
def set_managed(field, model, cls):
field.rel.through._meta.managed = model._meta.managed or cls._meta.managed
add_lazy_relation(klass, field, to_model, set_managed)
elif isinstance(field.rel.to, basestring):
to = klass._meta.object_name
to_model = klass
managed = klass._meta.managed
else:
to = field.rel.to._meta.object_name
to_model = field.rel.to
managed = klass._meta.managed or to_model._meta.managed
name = '%s_%s' % (klass._meta.object_name, field.name)
if field.rel.to == RECURSIVE_RELATIONSHIP_CONSTANT or to == klass._meta.object_name:
from_ = 'from_%s' % to.lower()
to = 'to_%s' % to.lower()
else:
from_ = klass._meta.object_name.lower()
to = to.lower()
meta = type(
'Meta', (object, ), {
'db_table': field._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'unique_together': (from_, to),
'verbose_name': '%(from)s-%(to)s relationship' % {
'from': from_,
'to': to
},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {
'from': from_,
'to': to
},
})
# Construct and return the new class.
return type(
name, (models.Model, ), {
'Meta': meta,
'__module__': klass.__module__,
from_: models.ForeignKey(klass, related_name='%s+' % name),
to: models.ForeignKey(
to_model, related_name='%s+' % name, unique=True)
})
def create_many_to_many_intermediary_model(field, klass):
"""
Copied from django, but uses FKToVersion for the
'from' field. Fields are also always called 'from' and 'to'
to avoid problems between version combined models.
"""
managed = True
if isinstance(field.rel.to, basestring) and field.rel.to != \
related.RECURSIVE_RELATIONSHIP_CONSTANT:
to_model = field.rel.to
to = to_model.split('.')[-1]
def set_managed(field, model, cls):
managed = model._meta.managed or cls._meta.managed
if issubclass(cls, VersionView):
managed = False
field.rel.through._meta.managed = managed
related.add_lazy_relation(klass, field, to_model, set_managed)
elif isinstance(field.rel.to, basestring):
to = klass._meta.object_name
to_model = klass
managed = klass._meta.managed
else:
to = field.rel.to._meta.object_name
to_model = field.rel.to
managed = klass._meta.managed or to_model._meta.managed
if issubclass(klass, VersionView):
managed = False
name = '%s_%s' % (klass._meta.object_name, field.name)
if field.rel.to == related.RECURSIVE_RELATIONSHIP_CONSTANT or \
to == klass._meta.object_name:
from_ = 'from_%s' % to.lower()
to = 'to_%s' % to.lower()
else:
from_ = klass._meta.object_name.lower()
to = to.lower()
meta = type('Meta', (object,), {
'db_table': field._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'db_tablespace': klass._meta.db_tablespace,
'unique_together': ('from', 'to'),
'verbose_name': '%(from)s-%(to)s relationship' % {'from': from_,
'to': to},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {
'from': from_, 'to': to},
})
# Construct and return the new class.
return type(name, (models.Model,), {
'Meta': meta,
'__module__': klass.__module__,
'from': FKToVersion(klass, related_name='%s+' % name,
db_tablespace=field.db_tablespace),
'to': models.ForeignKey(to_model, related_name='%s+' % name,
db_tablespace=field.db_tablespace)
})
def contribute_to_class(self, model, name):
self.__m2m_name = name
# Call Field, not super, to skip Django's ManyToManyField extra stuff
# we don't need
ListField.contribute_to_class(self, model, name)
# Do the rest after resolving the 'to' relation
add_lazy_relation(model, self, self._mm2m_to_or_name,
self.contribute_after_resolving)
def contribute_to_class(self, model, name):
self.__m2m_name = name
# Call Field, not super, to skip Django's ManyToManyField extra stuff
# we don't need
ListField.contribute_to_class(self, model, name)
# Do the rest after resolving the 'to' relation
add_lazy_relation(model, self, self._mm2m_to_or_name,
self.contribute_after_resolving)
def contribute_to_class(self):
if isinstance(self.model, six.string_types) or self.model._meta.pk is None:
def resolve_related_class(rel, model, cls):
rel.model = model
rel.do_related_class()
add_lazy_relation(self.field.model, self, self.model,
resolve_related_class)
else:
self.do_related_class()
def contribute_to_class(self, cls, name):
super(MaxCardinalityManyToManyField, self).contribute_to_class(cls, name)
if self.max_cardinality or self.reverse_max_cardinality:
through = self.rel.through
if through:
if isinstance(through, basestring):
add_lazy_relation(cls, self, through,
lambda self, through, cls: self.__connect_through_signals(through))
else:
self.__connect_through_signals(through)
def create_many_to_many_intermediary_model(field, klass):
"""
This function is a large copy/paste from django in order to construct
correct through tables for `ManyToManyField` relationships.
"""
from django.db import models
from django_unsigned_fields.fields import UnsignedForeignKey
from django.db.models.fields.related import (
add_lazy_relation,
RECURSIVE_RELATIONSHIP_CONSTANT,
)
managed = True
if isinstance(field.rel.to, six.string_types) and field.rel.to != RECURSIVE_RELATIONSHIP_CONSTANT:
to_model = field.rel.to
to = to_model.split('.')[-1]
def set_managed(field, model, cls):
field.rel.through._meta.managed = model._meta.managed or cls._meta.managed
add_lazy_relation(klass, field, to_model, set_managed)
elif isinstance(field.rel.to, six.string_types):
to = klass._meta.object_name
to_model = klass
managed = klass._meta.managed
else:
to = field.rel.to._meta.object_name
to_model = field.rel.to
managed = klass._meta.managed or to_model._meta.managed
name = '%s_%s' % (klass._meta.object_name, field.name)
if field.rel.to == RECURSIVE_RELATIONSHIP_CONSTANT or to == klass._meta.object_name:
from_ = 'from_%s' % to.lower()
to = 'to_%s' % to.lower()
else:
from_ = klass._meta.model_name
to = to.lower()
meta = type(str('Meta'), (object,), {
'db_table': field._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'db_tablespace': klass._meta.db_tablespace,
'unique_together': (from_, to),
'verbose_name': '%(from)s-%(to)s relationship' % {'from': from_, 'to': to},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {'from': from_, 'to': to},
'apps': field.model._meta.apps,
})
to_field_klass = UnsignedForeignKey if field.to_unsigned else models.ForeignKey
from_field_klass = UnsignedForeignKey if field.from_unsigned else models.ForeignKey
# Construct and return the new class.
return type(str(name), (models.Model,), {
'Meta': meta,
'__module__': klass.__module__,
from_: from_field_klass(klass, related_name='%s+' % name, db_tablespace=field.db_tablespace, db_constraint=field.rel.db_constraint),
to: to_field_klass(to_model, related_name='%s+' % name, db_tablespace=field.db_tablespace, db_constraint=field.rel.db_constraint)
})
def __new__(cls, name, bases, attrs):
new_cls = super().__new__(cls, name, bases, attrs)
new_cls._meta.custom_fields_inheritance_by_model = {}
new_cls._meta.custom_fields_inheritance_by_path = {}
# for each field in custom field inheritance, call
# `add_custom_field_inheritance` - it will be called lazy, only when
# model will be loaded
for field_path, model in new_cls.custom_fields_inheritance.items():
add_lazy_relation(new_cls, field_path, model,
add_custom_field_inheritance)
return new_cls
def contribute_to_class(self, cls, name):
if VERSION < (1, 7):
self.name = self.column = self.attname = name
else:
self.set_attributes_from_name(name)
self.model = cls
self.opts = cls._meta
cls._meta.add_field(self)
setattr(cls, name, self)
if not cls._meta.abstract:
# rel.to renamed to remote_field.model in Django 1.9
if VERSION >= (1, 9):
if isinstance(self.remote_field.model, six.string_types):
def resolve_related_class(cls, model, field):
field.remote_field.model = model
lazy_related_operation(resolve_related_class,
cls,
self.remote_field.model,
field=self)
else:
if isinstance(self.rel.to, six.string_types):
def resolve_related_class(field, model, cls):
field.rel.to = model
add_lazy_relation(cls, self, self.rel.to,
resolve_related_class)
if isinstance(self.through, six.string_types):
if VERSION >= (1, 9):
def resolve_related_class(cls, model, field):
self.through = model
self.remote_field.through = model
self.post_through_setup(cls)
lazy_related_operation(resolve_related_class,
cls,
self.through,
field=self)
else:
def resolve_related_class(field, model, cls):
self.through = model
_remote_field(self).through = model
self.post_through_setup(cls)
add_lazy_relation(cls, self, self.through,
resolve_related_class)
else:
self.post_through_setup(cls)
def create_sorted_many_to_many_intermediate_model(field, klass):
from django.db import models
managed = True
if isinstance(field.rel.to, six.string_types) and field.rel.to != RECURSIVE_RELATIONSHIP_CONSTANT:
to_model = field.rel.to
to = to_model.split('.')[-1]
def set_managed(field, model, cls):
field.rel.through._meta.managed = model._meta.managed or cls._meta.managed
add_lazy_relation(klass, field, to_model, set_managed)
elif isinstance(field.rel.to, six.string_types):
to = klass._meta.object_name
to_model = klass
managed = klass._meta.managed
else:
to = field.rel.to._meta.object_name
to_model = field.rel.to
managed = klass._meta.managed or to_model._meta.managed
name = '%s_%s' % (klass._meta.object_name, field.name)
if field.rel.to == RECURSIVE_RELATIONSHIP_CONSTANT or to == klass._meta.object_name:
from_ = 'from_%s' % to.lower()
to = 'to_%s' % to.lower()
else:
from_ = klass._meta.model_name
to = to.lower()
meta = type('Meta', (object,), {
'db_table': field._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'db_tablespace': klass._meta.db_tablespace,
'unique_together': (from_, to),
'ordering': (field.sort_value_field_name,),
'verbose_name': '%(from)s-%(to)s relationship' % {'from': from_, 'to': to},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {'from': from_, 'to': to},
'apps': field.model._meta.apps,
})
# Construct and return the new class.
def default_sort_value(name):
model = models.get_model(klass._meta.app_label, name)
return model._default_manager.count()
default_sort_value = curry(default_sort_value, name)
return type(str(name), (models.Model,), {
'Meta': meta,
'__module__': klass.__module__,
from_: models.ForeignKey(klass, related_name='%s+' % name, db_tablespace=field.db_tablespace, db_constraint=field.rel.db_constraint),
to: models.ForeignKey(to_model, related_name='%s+' % name, db_tablespace=field.db_tablespace, db_constraint=field.rel.db_constraint),
field.sort_value_field_name: models.IntegerField(default=default_sort_value),
'_sort_field_name': field.sort_value_field_name,
'_from_field_name': from_,
'_to_field_name': to,
})
def contribute_to_class(self, cls, name):
super(ImplicitRoleField, self).contribute_to_class(cls, name)
setattr(cls, self.name, ImplicitRoleDescriptor(self))
if not hasattr(cls, '__implicit_role_fields'):
setattr(cls, '__implicit_role_fields', [])
getattr(cls, '__implicit_role_fields').append(self)
post_save.connect(self._post_save, cls, True, dispatch_uid='implicit-role-post-save')
post_delete.connect(self._post_delete, cls, True, dispatch_uid='implicit-role-post-delete')
add_lazy_relation(cls, self, "self", self.bind_m2m_changed)
def setup(self, this_model):
super(DependOnRelated,self).setup(this_model)
# FIXME: this should not be necessary
if self.other_model == related.RECURSIVE_RELATIONSHIP_CONSTANT:
self.other_model = self.this_model
if isinstance(self.other_model,(str,unicode)):
# if ``other_model`` is a string, it certainly is a lazy relation.
related.add_lazy_relation(self.this_model, None, self.other_model, self.resolved_model)
else:
# otherwise it can be resolved directly
self.resolved_model(None,self.other_model,None)
def validate_not_to_tenant_model(field, to, model):
"""
Make sure the `to` relationship is not pointing to an instance of
`TenantModelBase`.
"""
if isinstance(to, string_types):
add_lazy_relation(model, field, to, validate_not_to_tenant_model)
elif isinstance(to, TenantModelBase):
remove_from_app_cache(model, quiet=True)
raise ImproperlyConfigured(
"`%s.%s`'s `to` option` can't point to an instance of "
"`TenantModelBase` since it's not one itself." %
(model.__name__, field.name))
def setup(self, this_model):
super(DependOnRelated,self).setup(this_model)
# FIXME: this should not be necessary
if self.other_model == related.RECURSIVE_RELATIONSHIP_CONSTANT:
self.other_model = self.this_model
if isinstance(self.other_model,(str,unicode)):
# if ``other_model`` is a string, it certainly is a lazy relation.
related.add_lazy_relation(self.this_model, None, self.other_model, self.resolved_model)
else:
# otherwise it can be resolved directly
self.resolved_model(None,self.other_model,None)
def _prepare(cls):
"""
Creates some methods once self._meta has been populated.
"""
opts = cls._meta
opts._prepare(cls)
if opts.order_with_respect_to:
cls.get_next_in_order = curry(cls._get_next_or_previous_in_order,
is_next=True)
cls.get_previous_in_order = curry(
cls._get_next_or_previous_in_order, is_next=False)
# defer creating accessors on the foreign class until we are
# certain it has been created
def make_foreign_order_accessors(field, model, cls):
setattr(field.rel.to, 'get_%s_order' % cls.__name__.lower(),
curry(method_get_order, cls))
setattr(field.rel.to, 'set_%s_order' % cls.__name__.lower(),
curry(method_set_order, cls))
add_lazy_relation(cls, opts.order_with_respect_to,
opts.order_with_respect_to.rel.to,
make_foreign_order_accessors)
# Give the class a docstring -- its definition.
if cls.__doc__ is None:
cls.__doc__ = "%s(%s)" % (cls.__name__, ", ".join(
[f.attname for f in opts.fields]))
if hasattr(cls, 'get_absolute_url'):
cls.get_absolute_url = update_wrapper(
curry(get_absolute_url, opts, cls.get_absolute_url),
cls.get_absolute_url)
if hasattr(cls, 'get_resource_url_list'):
cls.get_resource_url_list = staticmethod(
curry(get_resource_url_list, opts, cls.get_resource_url_list))
if hasattr(cls, 'get_resource_url_count'):
cls.get_resource_url_count = update_wrapper(
curry(get_resource_url_count, opts,
cls.get_resource_url_count), cls.get_resource_url_count)
if hasattr(cls, 'get_resource_url_detail'):
cls.get_resource_url_detail = update_wrapper(
curry(get_resource_url_detail, opts,
cls.get_resource_url_detail),
cls.get_resource_url_detail)
signals.class_prepared.send(sender=cls)
def create_sorted_many_to_many_intermediate_model(field, klass):
from django.db import models
managed = True
if isinstance(field.rel.to, basestring) and field.rel.to != RECURSIVE_RELATIONSHIP_CONSTANT:
to_model = field.rel.to
to = to_model.split('.')[-1]
def set_managed(field, model, cls):
field.rel.through._meta.managed = model._meta.managed or cls._meta.managed
add_lazy_relation(klass, field, to_model, set_managed)
elif isinstance(field.rel.to, basestring):
to = klass._meta.object_name
to_model = klass
managed = klass._meta.managed
else:
to = field.rel.to._meta.object_name
to_model = field.rel.to
managed = klass._meta.managed or to_model._meta.managed
name = '%s_%s' % (klass._meta.object_name, field.name)
if field.rel.to == RECURSIVE_RELATIONSHIP_CONSTANT or to == klass._meta.object_name:
from_ = 'from_%s' % to.lower()
to = 'to_%s' % to.lower()
else:
from_ = klass._meta.object_name.lower()
to = to.lower()
meta = type('Meta', (object,), {
'db_table': field._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'unique_together': (from_, to),
'ordering': (SORT_VALUE_FIELD_NAME,),
'verbose_name': '%(from)s-%(to)s relationship' % {'from': from_, 'to': to},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {'from': from_, 'to': to},
})
# Construct and return the new class.
def default_sort_value(name):
model = models.get_model(klass._meta.app_label, name)
return model._default_manager.count()
default_sort_value = curry(default_sort_value, name)
return type(name, (models.Model,), {
'Meta': meta,
'__module__': klass.__module__,
from_: models.ForeignKey(klass, related_name='%s+' % name),
to: models.ForeignKey(to_model, related_name='%s+' % name),
SORT_VALUE_FIELD_NAME: models.IntegerField(default=default_sort_value),
'_sort_field_name': SORT_VALUE_FIELD_NAME,
'_from_field_name': from_,
'_to_field_name': to,
})
def contribute_to_class(self, cls, name):
super(PolymorphicTypeField, self).contribute_to_class(cls, name)
polymorphic_type = self.rel.polymorphic_type
if (isinstance(polymorphic_type, string_types) or
polymorphic_type._meta.pk is None):
def resolve_polymorphic_type(field, model, cls):
field.validate_polymorphic_type(model)
field.rel.polymorphic_type = model
field.do_polymorphic_type(model)
add_lazy_relation(
cls, self, polymorphic_type, resolve_polymorphic_type
)
else:
self.do_polymorphic_type(polymorphic_type)
def contribute_to_class(self, cls, name, **kwargs):
super(RelatedBitField, self).contribute_to_class(cls, name, **kwargs)
other = self.fake_rel.to
if isinstance(other, six.string_types) or other._meta.pk is None:
def resolve_related_class(field, model, cls):
rel = field.fake_rel
rel.to = model
rel.field_name = rel.field_name or model._meta.pk.name
add_lazy_relation(cls, self, other, resolve_related_class)
else:
rel = self.fake_rel
rel.field_name = rel.field_name or other._meta.pk.name
def contribute_to_class(self, cls, name):
super(PolymorphicTypeField, self).contribute_to_class(cls, name)
polymorphic_type = self.rel.polymorphic_type
if (isinstance(polymorphic_type, string_types) or
polymorphic_type._meta.pk is None):
def resolve_polymorphic_type(field, model, cls):
field.validate_polymorphic_type(model)
field.rel.polymorphic_type = model
field.do_polymorphic_type(model)
add_lazy_relation(
cls, self, polymorphic_type, resolve_polymorphic_type
)
else:
self.do_polymorphic_type(polymorphic_type)
def contribute_to_class(self, cls, name):
self.name = self.column = name
self.model = cls
cls._meta.add_field(self)
setattr(cls, name, self)
if not cls._meta.abstract:
if isinstance(self.through, basestring):
def resolve_related_class(field, model, cls):
self.through = model
self.post_through_setup(cls)
add_lazy_relation(
cls, self, self.through, resolve_related_class
)
else:
self.post_through_setup(cls)
def contribute_to_class(self, cls, name):
super(GenericManyToManyField, self).contribute_to_class(cls, name)
self.name = self.column = name
self.model = cls
cls._meta.add_field(self)
setattr(cls, self.name, ReverseGenericManyRelatedObjectsDescriptor(self))
if not cls._meta.abstract:
if isinstance(self.through, basestring):
def resolve_related_class(field, model, cls):
self.through = model
add_lazy_relation(
cls, self, self.through, resolve_related_class
)
def validate_through(cls, field, rel_to, model):
"""
Make sure the related fields with a specified through points to an
instance of `TenantModelBase`.
"""
through = field.rel.through
if isinstance(through, string_types):
add_lazy_relation(model, field, through, cls.validate_through)
elif not isinstance(through, cls):
del cls.references[model]
remove_from_app_cache(model, quiet=True)
raise ImproperlyConfigured(
"Since `%s.%s` is originating from an instance of "
"`TenantModelBase` its `through` option must also be pointing "
"to one." % (model.__name__, field.name))
def contribute_to_class(self, cls, name):
self.name = self.column = name
self.model = cls
cls._meta.add_field(self)
setattr(cls, name, self)
if not cls._meta.abstract:
if isinstance(self.through, basestring):
def resolve_related_class(field, model, cls):
self.through = model
self.post_through_setup(cls)
add_lazy_relation(
cls, self, self.through, resolve_related_class
)
else:
self.post_through_setup(cls)
def contribute_to_class(self, cls, name):
"""
Replace the descriptor with our custom descriptor, so that the
position field (which is saved in the formfield clean()) gets saved
"""
if self.sort_field_name is not None:
def resolve_sort_field(field, model, cls):
field.sort_field = model._meta.get_field(field.sort_field_name)
if isinstance(self.rel.through, basestring):
add_lazy_relation(cls, self, self.rel.through, resolve_sort_field)
else:
resolve_sort_field(self, self.rel.through, cls)
super(ManyToManyField, self).contribute_to_class(cls, name)
if self.sort_field_name is not None:
setattr(cls, self.name, SortableReverseManyRelatedObjectsDescriptor(self))
def validate_not_to_tenant_model(field, to, model):
"""
Make sure the `to` relationship is not pointing to an instance of
`TenantModelBase`.
"""
if isinstance(to, basestring):
add_lazy_relation(model, field, to, validate_not_to_tenant_model)
elif isinstance(to, TenantModelBase):
remove_from_app_cache(model, quiet=True)
raise ImproperlyConfigured(
"`%s.%s`'s `to` option` can't point to an instance of "
"`TenantModelBase` since it's not one itself." % (
model.__name__, field.name
)
)
def validate_through(cls, field, rel_to, model):
"""
Make sure the related fields with a specified through points to an
instance of `TenantModelBase`.
"""
through = field.rel.through
if isinstance(through, basestring):
add_lazy_relation(model, field, through, cls.validate_through)
elif not isinstance(through, cls):
del cls.references[model]
remove_from_app_cache(model, quiet=True)
raise ImproperlyConfigured(
"Since `%s.%s` is originating from an instance of "
"`TenantModelBase` its `through` option must also be pointing "
"to one." % (model.__name__, field.name)
)
def contribute_to_class(self, cls, name):
if not self.sorted:
return super(SortedManyToManyField,
self).contribute_to_class(cls, name)
# To support multiple relations to self, it's useful to have a non-None
# related name on symmetrical relations for internal reasons. The
# concept doesn't make a lot of sense externally ("you want me to
# specify *what* on my non-reversible relation?!"), so we set it up
# automatically. The funky name reduces the chance of an accidental
# clash.
if self.rel.symmetrical and (self.rel.to == "self"
or self.rel.to == cls._meta.object_name):
self.rel.related_name = "%s_rel_+" % name
super(ManyToManyField, self).contribute_to_class(cls, name)
# The intermediate m2m model is not auto created if:
# 1) There is a manually specified intermediate, or
# 2) The class owning the m2m field is abstract.
if not self.rel.through and not cls._meta.abstract:
self.rel.through = create_sorted_many_to_many_intermediate_model(
self, cls)
# Add the descriptor for the m2m relation
setattr(cls, self.name,
ReverseSortedManyRelatedObjectsDescriptor(self))
# Set up the accessor for the m2m table name for the relation
self.m2m_db_table = curry(self._get_m2m_db_table, cls._meta)
# Populate some necessary rel arguments so that cross-app relations
# work correctly.
if isinstance(self.rel.through, six.string_types):
def resolve_through_model(field, model, cls):
field.rel.through = model
add_lazy_relation(cls, self, self.rel.through,
resolve_through_model)
if hasattr(cls._meta, 'duplicate_targets'): # Django<1.5
if isinstance(self.rel.to, six.string_types):
target = self.rel.to
else:
target = self.rel.to._meta.db_table
cls._meta.duplicate_targets[self.column] = (target, "m2m")
def _set_model(self, model):
# We need to know the model to generate a valid key for the lookup but
# EmbeddedModelFields are not contributed_to_class if used in ListFields
# (and friends), so we can only know the model when the ListField sets
# our 'model' attribute in its contribute_to_class method.
if model is not None and isinstance(self.embedded_model, basestring):
# The model argument passed to __init__ was a string, so we need
# to make sure to resolve that string to the corresponding model
# class, similar to relation fields. We abuse some of the relation
# fields' code to do the lookup here:
def _resolve_lookup(self_, resolved_model, model):
self.embedded_model = resolved_model
from django.db.models.fields.related import add_lazy_relation
add_lazy_relation(model, self, self.embedded_model, _resolve_lookup)
self._model = model
def create_one_to_many_intermediary_model(field, klass):
"""
Identical to the 'create_many_to_many_intermediary_model' implementation
from django.db.models.fields.related, but with a 'unique' constraint added
to the receiving relation.
"""
from django.db import models
managed = True
if isinstance(field.rel.to, basestring) and field.rel.to != RECURSIVE_RELATIONSHIP_CONSTANT:
to_model = field.rel.to
to = to_model.split('.')[-1]
def set_managed(field, model, cls):
field.rel.through._meta.managed = model._meta.managed or cls._meta.managed
add_lazy_relation(klass, field, to_model, set_managed)
elif isinstance(field.rel.to, basestring):
to = klass._meta.object_name
to_model = klass
managed = klass._meta.managed
else:
to = field.rel.to._meta.object_name
to_model = field.rel.to
managed = klass._meta.managed or to_model._meta.managed
name = '%s_%s' % (klass._meta.object_name, field.name)
if field.rel.to == RECURSIVE_RELATIONSHIP_CONSTANT or to == klass._meta.object_name:
from_ = 'from_%s' % to.lower()
to = 'to_%s' % to.lower()
else:
from_ = klass._meta.object_name.lower()
to = to.lower()
meta = type('Meta', (object,), {
'db_table': field._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'unique_together': (from_, to),
'verbose_name': '%(from)s-%(to)s relationship' % {'from': from_, 'to': to},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {'from': from_, 'to': to},
})
# Construct and return the new class.
return type(name, (models.Model,), {
'Meta': meta,
'__module__': klass.__module__,
from_: models.ForeignKey(klass, related_name='%s+' % name),
to: models.ForeignKey(to_model, related_name='%s+' % name, unique=True)
})
def _set_model(self, model):
# EmbeddedModelFields are not contribute[d]_to_class if using within
# ListFields (and friends), so we can only know the model field is
# used in when the IterableField sets our 'model' attribute in its
# contribute_to_class method.
# We need to know the model to generate a valid key for the lookup.
if model is not None and isinstance(self.embedded_model, basestring):
# The model argument passed to __init__ was a string, so we need
# to make sure to resolve that string to the corresponding model
# class, similar to relation fields. We abuse some of the
# relation fields' code to do the lookup here:
def _resolve_lookup(self_, resolved_model, model):
self.embedded_model = resolved_model
from django.db.models.fields.related import add_lazy_relation
add_lazy_relation(model, self, self.embedded_model, _resolve_lookup)
self._model = model
def compat_add_lazy_relation(cls, field, relation, operation):
if add_lazy_relation is not None:
return add_lazy_relation(cls, field, relation, operation)
# Rearrange args for new Apps.lazy_model_operation
def function(local, related, field):
return operation(field, related, local)
lazy_related_operation(function, cls, relation, field=field)
def model_prepared(self, sender, **kwargs):
'''
Wait for any field dependencies to be resolved, then call finalize().
'''
model = sender
deps = self.get_field_dependencies(model)
if deps:
count = [len(deps)]
def dependency_resolved(*args):
count[0] = count[0] - 1
if count[0] == 0:
self.finalize(model)
for dep in deps:
add_lazy_relation(model, None, dep.rel.to, dependency_resolved)
else:
self.finalize(model)
def compat_add_lazy_relation(cls, field, relation, operation):
if add_lazy_relation is not None:
return add_lazy_relation(cls, field, relation, operation)
# Rearrange args for new Apps.lazy_model_operation
def function(local, related, field):
return operation(field, related, local)
lazy_related_operation(function, cls, relation, field=field)
def contribute_to_class(self, cls, name):
if VERSION < (1, 7):
self.name = self.column = self.attname = name
else:
self.set_attributes_from_name(name)
self.model = cls
self.opts = cls._meta
cls._meta.add_field(self)
setattr(cls, name, self)
if not cls._meta.abstract:
# rel.to renamed to remote_field.model in Django 1.9
if VERSION >= (1, 9):
if isinstance(self.remote_field.model, six.string_types):
def resolve_related_class(cls, model, field):
field.remote_field.model = model
lazy_related_operation(
resolve_related_class, cls, self.remote_field.model, field=self
)
else:
if isinstance(self.rel.to, six.string_types):
def resolve_related_class(field, model, cls):
field.rel.to = model
add_lazy_relation(cls, self, self.rel.to, resolve_related_class)
if isinstance(self.through, six.string_types):
if VERSION >= (1, 9):
def resolve_related_class(cls, model, field):
self.through = model
self.remote_field.through = model
self.post_through_setup(cls)
lazy_related_operation(
resolve_related_class, cls, self.through, field=self
)
else:
def resolve_related_class(field, model, cls):
self.through = model
_remote_field(self).through = model
self.post_through_setup(cls)
add_lazy_relation(
cls, self, self.through, resolve_related_class
)
else:
self.post_through_setup(cls)
def setup(self, this_model):
super(DependOnRelated, self).setup(this_model)
# FIXME: this should not be necessary
if self.other_model == related.RECURSIVE_RELATIONSHIP_CONSTANT:
self.other_model = self.this_model
if isinstance(self.other_model, six.string_types):
# if ``other_model`` is a string, it certainly is a lazy relation.
try:
def function(local, related, field):
return self.resolved_model(field, related, local)
related.lazy_related_operation(function, self.this_model, self.other_model, field=None)
except AttributeError: # Django<2.0
related.add_lazy_relation(self.this_model, None, self.other_model, self.resolved_model)
else:
# otherwise it can be resolved directly
self.resolved_model(None, self.other_model, None)
def contribute_to_class(self, cls, name):
"""
Replace the descriptor with our custom descriptor, so that the
position field (which is saved in the formfield clean()) gets saved
"""
if self.sort_field_name is not None:
def resolve_sort_field(field, model, cls):
field.sort_field = model._meta.get_field(field.sort_field_name)
if isinstance(self.rel.through, basestring):
add_lazy_relation(cls, self, self.rel.through,
resolve_sort_field)
else:
resolve_sort_field(self, self.rel.through, cls)
super(ManyToManyField, self).contribute_to_class(cls, name)
if self.sort_field_name is not None:
setattr(cls, self.name,
SortableReverseManyRelatedObjectsDescriptor(self))
def contribute_to_class(self, cls, name):
self.item_field.model = cls
self.item_field.name = name
super(AbstractIterableField, self).contribute_to_class(cls, name)
# If items' field uses SubfieldBase we also need to.
item_metaclass = getattr(self.item_field, '__metaclass__', None)
if item_metaclass and issubclass(item_metaclass, models.SubfieldBase):
setattr(cls, self.name, Creator(self))
if isinstance(self.item_field, models.ForeignKey) and isinstance(self.item_field.rel.to, six.string_types):
"""
If rel.to is a string because the actual class is not yet defined, look up the
actual class later. Refer to django.models.fields.related.RelatedField.contribute_to_class.
"""
def _resolve_lookup(_, resolved_model, __):
self.item_field.rel.to = resolved_model
self.item_field.do_related_class(self, cls)
add_lazy_relation(cls, self, self.item_field.rel.to, _resolve_lookup)
def validate_related_name(cls, field, rel_to, model):
"""
Make sure that related fields pointing to non-tenant models specify
a related name containing a %(class)s format placeholder.
"""
if isinstance(rel_to, string_types):
add_lazy_relation(model, field, rel_to, cls.validate_related_name)
elif not isinstance(rel_to, TenantModelBase):
related_name = cls.references[model].related_names[field.name]
if (related_name is not None
and not (field.rel.is_hidden()
or '%(class)s' in related_name)):
del cls.references[model]
remove_from_app_cache(model, quiet=True)
raise ImproperlyConfigured(
"Since `%s.%s` is originating from an instance "
"of `TenantModelBase` and not pointing to one "
"its `related_name` option must ends with a "
"'+' or contain the '%%(class)s' format "
"placeholder." % (model.__name__, field.name))
def _set_model(self, model):
"""
Resolves embedded model class once the field knows the model it
belongs to.
If the model argument passed to __init__ was a string, we need
to make sure to resolve that string to the corresponding model
class, similar to relation fields.
However, we need to know our own model to generate a valid key
for the embedded model class lookup and EmbeddedModelFields are
not contributed_to_class if used in iterable fields. Thus we
rely on the collection field telling us its model (by setting
our "model" attribute in its contribute_to_class method).
"""
self._model = model
if model is not None and isinstance(self.embedded_model, basestring):
def _resolve_lookup(self_, resolved_model, model):
self.embedded_model = resolved_model
add_lazy_relation(model, self, self.embedded_model, _resolve_lookup)
def validate_related_name(cls, field, rel_to, model):
"""
Make sure that related fields pointing to non-tenant models specify
a related name containing a %(class)s format placeholder.
"""
if isinstance(rel_to, basestring):
add_lazy_relation(model, field, rel_to, cls.validate_related_name)
elif not isinstance(rel_to, cls):
related_name = cls.references[model].related_names[field.name]
if (related_name is not None and
not (field.rel.is_hidden() or '%(class)s' in related_name)):
del cls.references[model]
remove_from_app_cache(model, quiet=True)
raise ImproperlyConfigured(
"Since `%s.%s` is originating from an instance "
"of `TenantModelBase` and not pointing to one "
"its `related_name` option must ends with a "
"'+' or contain the '%%(class)s' format "
"placeholder." % (model.__name__, field.name)
)
def contribute_to_class(self, cls, name):
self.item_field.model = cls
self.item_field.name = name
super(AbstractIterableField, self).contribute_to_class(cls, name)
# If items' field uses SubfieldBase we also need to.
item_metaclass = getattr(self.item_field, '__metaclass__', None)
if item_metaclass and issubclass(item_metaclass, models.SubfieldBase):
setattr(cls, self.name, Creator(self))
if isinstance(self.item_field, models.ForeignKey) and isinstance(self.item_field.rel.to, basestring):
"""
If rel.to is a string because the actual class is not yet defined, look up the
actual class later. Refer to django.models.fields.related.RelatedField.contribute_to_class.
"""
def _resolve_lookup(_, resolved_model, __):
self.item_field.rel.to = resolved_model
self.item_field.do_related_class(self, cls)
add_lazy_relation(cls, self, self.item_field.rel.to, _resolve_lookup)
def _set_model(self, model):
"""
Resolves embedded model class once the field knows the model it
belongs to.
If the model argument passed to __init__ was a string, we need
to make sure to resolve that string to the corresponding model
class, similar to relation fields.
However, we need to know our own model to generate a valid key
for the embedded model class lookup and EmbeddedModelFields are
not contributed_to_class if used in iterable fields. Thus we
rely on the collection field telling us its model (by setting
our "model" attribute in its contribute_to_class method).
"""
self._model = model
if model is not None and isinstance(self.embedded_model, basestring):
def _resolve_lookup(self_, resolved_model, model):
self.embedded_model = resolved_model
add_lazy_relation(model, self, self.embedded_model, _resolve_lookup)
def contribute_to_class(self, cls, name, **kwargs):
if not self.sorted:
return super(SortedManyToManyField, self).contribute_to_class(cls, name, **kwargs)
# To support multiple relations to self, it's useful to have a non-None
# related name on symmetrical relations for internal reasons. The
# concept doesn't make a lot of sense externally ("you want me to
# specify *what* on my non-reversible relation?!"), so we set it up
# automatically. The funky name reduces the chance of an accidental
# clash.
if self.rel.symmetrical and (self.rel.to == "self" or self.rel.to == cls._meta.object_name):
self.rel.related_name = "%s_rel_+" % name
super(_ManyToManyField, self).contribute_to_class(cls, name, **kwargs)
# The intermediate m2m model is not auto created if:
# 1) There is a manually specified intermediate, or
# 2) The class owning the m2m field is abstract.
if not self.rel.through and not cls._meta.abstract:
self.rel.through = self.create_intermediate_model(cls)
# Add the descriptor for the m2m relation
setattr(cls, self.name, SortedManyToManyDescriptor(self))
# Set up the accessor for the m2m table name for the relation
self.m2m_db_table = curry(self._get_m2m_db_table, cls._meta)
# Populate some necessary rel arguments so that cross-app relations
# work correctly.
if isinstance(self.rel.through, six.string_types):
def resolve_through_model(field, model, cls):
field.rel.through = model
add_lazy_relation(cls, self, self.rel.through, resolve_through_model)
if hasattr(cls._meta, 'duplicate_targets'): # Django<1.5
if isinstance(self.rel.to, six.string_types):
target = self.rel.to
else:
target = self.rel.to._meta.db_table
cls._meta.duplicate_targets[self.column] = (target, "m2m")
def __init__(self, cls, field, name, setup_reversed):
add_lazy_relation(cls, field, name, self.__setup)
self.__setup_reversed = setup_reversed
def create_many_to_many_intermediary_model(field, klass):
"""
Copied from django, but uses FKToVersion for the
'from' field. Fields are also always called 'from' and 'to'
to avoid problems between version combined models.
"""
managed = True
if (isinstance(field.remote_field.to, basestring) and
field.remote_field.to != related.RECURSIVE_RELATIONSHIP_CONSTANT):
to_model = field.remote_field.to
to = to_model.split('.')[-1]
def set_managed(field, model, cls):
managed = model._meta.managed or cls._meta.managed
if issubclass(cls, VersionView):
managed = False
field.remote_field.through._meta.managed = managed
related.add_lazy_relation(klass, field, to_model, set_managed)
elif isinstance(field.remote_field.to, basestring):
to = klass._meta.object_name
to_model = klass
managed = klass._meta.managed
else:
to = field.remote_field.to._meta.object_name
to_model = field.remote_field.to
managed = klass._meta.managed or to_model._meta.managed
if issubclass(klass, VersionView):
managed = False
name = '%s_%s' % (klass._meta.object_name, field.name)
if (field.remote_field.to == related.RECURSIVE_RELATIONSHIP_CONSTANT or
to == klass._meta.object_name):
from_ = 'from_%s' % to.lower()
to = 'to_%s' % to.lower()
else:
from_ = klass._meta.object_name.lower()
to = to.lower()
meta = type('Meta', (object,), {
'db_table': field._get_m2m_db_table(klass._meta),
'managed': managed,
'auto_created': klass,
'app_label': klass._meta.app_label,
'db_tablespace': klass._meta.db_tablespace,
'unique_together': ('from', 'to'),
'verbose_name': '%(from)s-%(to)s relationship' % {
'from': from_, 'to': to},
'verbose_name_plural': '%(from)s-%(to)s relationships' % {
'from': from_, 'to': to},
'apps': field.model._meta.apps,
})
# Construct and return the new class.
return type(str(name), (models.Model,), {
'Meta': meta,
'__module__': klass.__module__,
'from': FKToVersion(klass, related_name='%s+' % name,
db_tablespace=field.db_tablespace,
db_constraint=field.remote_field.db_constraint),
'to': models.ForeignKey(to_model, related_name='%s+' % name,
db_tablespace=field.db_tablespace,
db_constraint=field.remote_field.db_constraint)
})
def contribute_to_class(self, cls, virtual_only=False):
# Connect the descriptor for this field
setattr(cls, self.field.attname,
SourceGM2MDescriptor(self.field))
if cls._meta.abstract or cls._meta.swapped:
# do not do anything for abstract or swapped model classes
return
if not self.through:
self.set_init('through',
create_gm2m_intermediary_model(self.field, cls))
# we set through_fields to the default intermediary model's
# THROUGH_FIELDS as it carries fields assignments for
# ModelState instances
self.set_init('through_fields', THROUGH_FIELDS)
# set related name
if not self.field.model._meta.abstract and self.related_name:
self.set_init('related_name', self.related_name % {
'class': self.field.model.__name__.lower(),
'app_label': self.field.model._meta.app_label.lower()
})
def calc_field_names(rel):
# Extract field names from through model and stores them in
# rel.through_field (so that they are sent on deconstruct and
# passed to ModelState instances)
tf_dict = {}
if is_fake_model(rel.through):
# we populate the through field dict using rel.through_fields
# that was either provided or computed beforehand with the
# actual model
for f, k in zip(rel.through_fields,
('src', 'tgt', 'tgt_ct', 'tgt_fk')):
tf_dict[k] = f
rel.through._meta._field_names = tf_dict
return
if rel.through_fields:
tf_dict['src'], tf_dict['tgt'] = \
rel.through_fields[:2]
for gfk in rel.through._meta.private_fields:
if gfk.name == tf_dict['tgt']:
break
else:
raise FieldDoesNotExist(
'Generic foreign key "%s" does not exist in through '
'model "%s"' % (tf_dict['tgt'],
rel.through._meta.model_name)
)
tf_dict['tgt_ct'] = gfk.ct_field
tf_dict['tgt_fk'] = gfk.fk_field
else:
for f in rel.through._meta.fields:
# ETJ DEBUG
if (hasattr(f, 'rel') and f.remote_field \
and (f.remote_field.model == rel.field.model
or f.remote_field.model == '%s.%s' % (rel.field.model._meta.app_label,rel.field.model._meta.object_name)
or f.remote_field.model == rel.field.model._meta.object_name)):
# NOTE: Original code failed on Django 1.10
# if hasattr(f, 'rel') and f.remote_field \
# and (f.remote_field.model == rel.field.model
# or f.remote_field.model == '%s.%s' % (
# rel.field.model._meta.app_label,
# rel.field.model._meta.object_name)):
# END DEBUG
tf_dict['src'] = f.name
break
for f in rel.through._meta.private_fields:
if isinstance(f, ct.GenericForeignKey):
tf_dict['tgt'] = f.name
tf_dict['tgt_ct'] = f.ct_field
tf_dict['tgt_fk'] = f.fk_field
break
if not set(tf_dict.keys()).issuperset(('src', 'tgt')):
raise ValueError('Bad through model for GM2M relationship.')
rel.through._meta._field_names = tf_dict
# save the result in rel.through_fields so that it appears
# in the deconstruction. Without that there would be no way for
# a ModelState constructed from a migration to know which fields
# have which function, as all virtual fields are stripped
tf = []
for f in ('src', 'tgt', 'tgt_ct', 'tgt_fk'):
tf.append(tf_dict[f])
rel.set_init('through_fields', tf)
# resolve through model if it's provided as a string
if isinstance(self.through, six.string_types):
def resolve_through_model(r, model, c):
r.set_init('through', model)
calc_field_names(r)
add_lazy_relation(cls, self, self.through, resolve_through_model)
else:
calc_field_names(self)
self.related_model = cls
for rel in self.rels:
# we need to make sure the GM2MUnitRel's field instance is the
# right one. Indeed, if cls is derived from an abstract model
# where the GM2MField is defined, rel.field is the field linked
# to the abstract model
rel.field = self.field
rel.contribute_to_class()
