from django.db import backend, transaction from django.db.models import signals, get_model from django.db.models.fields import AutoField, Field, IntegerField, get_ul_class from django.db.models.related import RelatedObject from django.utils.text import capfirst from django.utils.translation import gettext_lazy, string_concat, ngettext from django.utils.functional import curry from django.core import validators from django import oldforms from django import newforms as forms from django.dispatch import dispatcher # For Python 2.3 if not hasattr(__builtins__, 'set'): from sets import Set as set # Values for Relation.edit_inline. TABULAR, STACKED = 1, 2 RECURSIVE_RELATIONSHIP_CONSTANT = 'self' pending_lookups = {} def add_lookup(rel_cls, field): name = field.rel.to module = rel_cls.__module__ key = (module, name) # Has the model already been loaded? # If so, resolve the string reference right away model = get_model(rel_cls._meta.app_label, field.rel.to, False) if model: field.rel.to = model field.do_related_class(model, rel_cls) else: # Mark the related field for later lookup pending_lookups.setdefault(key, []).append((rel_cls, field)) def do_pending_lookups(sender): other_cls = sender key = (other_cls.__module__, other_cls.__name__) for rel_cls, field in pending_lookups.setdefault(key, []): field.rel.to = other_cls field.do_related_class(other_cls, rel_cls) dispatcher.connect(do_pending_lookups, signal=signals.class_prepared) def manipulator_valid_rel_key(f, self, field_data, all_data): "Validates that the value is a valid foreign key" klass = f.rel.to try: klass._default_manager.get(**{f.rel.field_name: field_data}) except klass.DoesNotExist: raise validators.ValidationError, _("Please enter a valid %s.") % f.verbose_name #HACK class RelatedField(object): def contribute_to_class(self, cls, name): sup = super(RelatedField, self) # Add an accessor to allow easy determination of the related query path for this field self.related_query_name = curry(self._get_related_query_name, cls._meta) if hasattr(sup, 'contribute_to_class'): sup.contribute_to_class(cls, name) other = self.rel.to if isinstance(other, basestring): if other == RECURSIVE_RELATIONSHIP_CONSTANT: self.rel.to = cls.__name__ add_lookup(cls, self) else: self.do_related_class(other, cls) def set_attributes_from_rel(self): self.name = self.name or (self.rel.to._meta.object_name.lower() + '_' + self.rel.to._meta.pk.name) self.verbose_name = self.verbose_name or self.rel.to._meta.verbose_name self.rel.field_name = self.rel.field_name or self.rel.to._meta.pk.name def do_related_class(self, other, cls): self.set_attributes_from_rel() related = RelatedObject(other, cls, self) self.contribute_to_related_class(other, related) def get_db_prep_lookup(self, lookup_type, value): # If we are doing a lookup on a Related Field, we must be # comparing object instances. The value should be the PK of value, # not value itself. def pk_trace(value): # Value may be a primary key, or an object held in a relation. # If it is an object, then we need to get the primary key value for # that object. In certain conditions (especially one-to-one relations), # the primary key may itself be an object - so we need to keep drilling # down until we hit a value that can be used for a comparison. v = value try: while True: v = getattr(v, v._meta.pk.name) except AttributeError: pass return v if lookup_type == 'exact': return [pk_trace(value)] if lookup_type == 'in': return [pk_trace(v) for v in value] elif lookup_type == 'isnull': return [] raise TypeError, "Related Field has invalid lookup: %s" % lookup_type def _get_related_query_name(self, opts): # This method defines the name that can be used to identify this related object # in a table-spanning query. It uses the lower-cased object_name by default, # but this can be overridden with the "related_name" option. return self.rel.related_name or opts.object_name.lower() class SingleRelatedObjectDescriptor(object): # This class provides the functionality that makes the related-object # managers available as attributes on a model class, for fields that have # a single "remote" value, on the class pointed to by a related field. # In the example "place.restaurant", the restaurant attribute is a # SingleRelatedObjectDescriptor instance. def __init__(self, related): self.related = related def __get__(self, instance, instance_type=None): if instance is None: raise AttributeError, "%s must be accessed via instance" % self.related.opts.object_name params = {'%s__pk' % self.related.field.name: instance._get_pk_val()} rel_obj = self.related.model._default_manager.get(**params) return rel_obj def __set__(self, instance, value): if instance is None: raise AttributeError, "%s must be accessed via instance" % self.related.opts.object_name # Set the value of the related field setattr(value, self.related.field.rel.get_related_field().attname, instance) # Clear the cache, if it exists try: delattr(value, self.related.field.get_cache_name()) except AttributeError: pass class ReverseSingleRelatedObjectDescriptor(object): # This class provides the functionality that makes the related-object # managers available as attributes on a model class, for fields that have # a single "remote" value, on the class that defines the related field. # In the example "choice.poll", the poll attribute is a # ReverseSingleRelatedObjectDescriptor instance. def __init__(self, field_with_rel): self.field = field_with_rel def __get__(self, instance, instance_type=None): if instance is None: raise AttributeError, "%s must be accessed via instance" % self.field.name cache_name = self.field.get_cache_name() try: return getattr(instance, cache_name) except AttributeError: val = getattr(instance, self.field.attname) if val is None: # If NULL is an allowed value, return it. if self.field.null: return None raise self.field.rel.to.DoesNotExist other_field = self.field.rel.get_related_field() if other_field.rel: params = {'%s__pk' % self.field.rel.field_name: val} else: params = {'%s__exact' % self.field.rel.field_name: val} rel_obj = self.field.rel.to._default_manager.get(**params) setattr(instance, cache_name, rel_obj) return rel_obj def __set__(self, instance, value): if instance is None: raise AttributeError, "%s must be accessed via instance" % self._field.name # Set the value of the related field try: val = getattr(value, self.field.rel.get_related_field().attname) except AttributeError: val = None setattr(instance, self.field.attname, val) # Clear the cache, if it exists try: delattr(instance, self.field.get_cache_name()) except AttributeError: pass class ForeignRelatedObjectsDescriptor(object): # This class provides the functionality that makes the related-object # managers available as attributes on a model class, for fields that have # multiple "remote" values and have a ForeignKey pointed at them by # some other model. In the example "poll.choice_set", the choice_set # attribute is a ForeignRelatedObjectsDescriptor instance. def __init__(self, related): self.related = related # RelatedObject instance def __get__(self, instance, instance_type=None): if instance is None: raise AttributeError, "Manager must be accessed via instance" rel_field = self.related.field rel_model = self.related.model # Dynamically create a class that subclasses the related # model's default manager. superclass = self.related.model._default_manager.__class__ class RelatedManager(superclass): def get_query_set(self): return superclass.get_query_set(self).filter(**(self.core_filters)) def add(self, *objs): for obj in objs: setattr(obj, rel_field.name, instance) obj.save() add.alters_data = True def create(self, **kwargs): new_obj = self.model(**kwargs) self.add(new_obj) return new_obj 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(instance, 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) obj.save() else: raise rel_field.rel.to.DoesNotExist, "%r is not related to %r." % (obj, instance) remove.alters_data = True def clear(self): for obj in self.all(): setattr(obj, rel_field.name, None) obj.save() clear.alters_data = True manager = RelatedManager() manager.core_filters = {'%s__pk' % rel_field.name: getattr(instance, rel_field.rel.get_related_field().attname)} manager.model = self.related.model return manager def __set__(self, instance, value): if instance is None: raise AttributeError, "Manager must be accessed via instance" manager = self.__get__(instance) # If the foreign key can support nulls, then completely clear the related set. # Otherwise, just move the named objects into the set. if self.related.field.null: manager.clear() manager.add(*value) def create_many_related_manager(superclass): """Creates a manager that subclasses 'superclass' (which is a Manager) and adds behavior for many-to-many related objects.""" class ManyRelatedManager(superclass): def __init__(self, model=None, core_filters=None, instance=None, symmetrical=None, join_table=None, source_col_name=None, target_col_name=None): super(ManyRelatedManager, self).__init__() self.core_filters = core_filters self.model = model self.symmetrical = symmetrical self.instance = instance self.join_table = join_table self.source_col_name = source_col_name self.target_col_name = target_col_name self._pk_val = self.instance._get_pk_val() 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." % model) def get_query_set(self): return superclass.get_query_set(self).filter(**(self.core_filters)) def add(self, *objs): self._add_items(self.source_col_name, self.target_col_name, *objs) # If this is a symmetrical m2m relation to self, add the mirror entry in the m2m table if self.symmetrical: self._add_items(self.target_col_name, self.source_col_name, *objs) add.alters_data = True def remove(self, *objs): self._remove_items(self.source_col_name, self.target_col_name, *objs) # If this is a symmetrical m2m relation to self, remove the mirror entry in the m2m table if self.symmetrical: self._remove_items(self.target_col_name, self.source_col_name, *objs) remove.alters_data = True def clear(self): self._clear_items(self.source_col_name) # If this is a symmetrical m2m relation to self, clear the mirror entry in the m2m table if self.symmetrical: self._clear_items(self.target_col_name) clear.alters_data = True def create(self, **kwargs): new_obj = self.model(**kwargs) new_obj.save() self.add(new_obj) return new_obj create.alters_data = True def _add_items(self, source_col_name, target_col_name, *objs): # join_table: name of the m2m link table # source_col_name: the PK colname in join_table for the source object # target_col_name: the PK colname in join_table for the target object # *objs - objects to add. Either object instances, or primary keys of object instances. from django.db import connection # If there aren't any objects, there is nothing to do. if objs: # Check that all the objects are of the right type new_ids = set() for obj in objs: if isinstance(obj, self.model): new_ids.add(obj._get_pk_val()) else: new_ids.add(obj) # Add the newly created or already existing objects to the join table. # First find out which items are already added, to avoid adding them twice cursor = connection.cursor() cursor.execute("SELECT %s FROM %s WHERE %s = %%s AND %s IN (%s)" % \ (target_col_name, self.join_table, source_col_name, target_col_name, ",".join(['%s'] * len(new_ids))), [self._pk_val] + list(new_ids)) if cursor.rowcount is not None and cursor.rowcount != 0: existing_ids = set([row[0] for row in cursor.fetchmany(cursor.rowcount)]) else: existing_ids = set() # Add the ones that aren't there already for obj_id in (new_ids - existing_ids): cursor.execute("INSERT INTO %s (%s, %s) VALUES (%%s, %%s)" % \ (self.join_table, source_col_name, target_col_name), [self._pk_val, obj_id]) transaction.commit_unless_managed() def _remove_items(self, source_col_name, target_col_name, *objs): # source_col_name: the PK colname in join_table for the source object # target_col_name: the PK colname in join_table for the target object # *objs - objects to remove from django.db import connection # If there aren't any objects, there is nothing to do. if objs: # Check that all the objects are of the right type old_ids = set() for obj in objs: if isinstance(obj, self.model): old_ids.add(obj._get_pk_val()) else: old_ids.add(obj) # Remove the specified objects from the join table cursor = connection.cursor() cursor.execute("DELETE FROM %s WHERE %s = %%s AND %s IN (%s)" % \ (self.join_table, source_col_name, target_col_name, ",".join(['%s'] * len(old_ids))), [self._pk_val] + list(old_ids)) transaction.commit_unless_managed() def _clear_items(self, source_col_name): # source_col_name: the PK colname in join_table for the source object from django.db import connection cursor = connection.cursor() cursor.execute("DELETE FROM %s WHERE %s = %%s" % \ (self.join_table, source_col_name), [self._pk_val]) transaction.commit_unless_managed() return ManyRelatedManager class ManyRelatedObjectsDescriptor(object): # This class provides the functionality that makes the related-object # managers available as attributes on a model class, for fields that have # multiple "remote" values and have a ManyToManyField pointed at them by # some other model (rather than having a ManyToManyField themselves). # In the example "publication.article_set", the article_set attribute is a # ManyRelatedObjectsDescriptor instance. def __init__(self, related): self.related = related # RelatedObject instance def __get__(self, instance, instance_type=None): if instance is None: raise AttributeError, "Manager must be accessed via instance" # Dynamically create a class that subclasses the related # model's default manager. rel_model = self.related.model superclass = rel_model._default_manager.__class__ RelatedManager = create_many_related_manager(superclass) qn = backend.quote_name manager = RelatedManager( model=rel_model, core_filters={'%s__pk' % self.related.field.name: instance._get_pk_val()}, instance=instance, symmetrical=False, join_table=qn(self.related.field.m2m_db_table()), source_col_name=qn(self.related.field.m2m_reverse_name()), target_col_name=qn(self.related.field.m2m_column_name()) ) return manager def __set__(self, instance, value): if instance is None: raise AttributeError, "Manager must be accessed via instance" manager = self.__get__(instance) manager.clear() manager.add(*value) class ReverseManyRelatedObjectsDescriptor(object): # This class provides the functionality that makes the related-object # managers available as attributes on a model class, for fields that have # multiple "remote" values and have a ManyToManyField defined in their # model (rather than having another model pointed *at* them). # In the example "article.publications", the publications attribute is a # ReverseManyRelatedObjectsDescriptor instance. def __init__(self, m2m_field): self.field = m2m_field def __get__(self, instance, instance_type=None): if instance is None: raise AttributeError, "Manager must be accessed via instance" # Dynamically create a class that subclasses the related # model's default manager. rel_model=self.field.rel.to superclass = rel_model._default_manager.__class__ RelatedManager = create_many_related_manager(superclass) qn = backend.quote_name manager = RelatedManager( model=rel_model, core_filters={'%s__pk' % self.field.related_query_name(): instance._get_pk_val()}, instance=instance, symmetrical=(self.field.rel.symmetrical and instance.__class__ == rel_model), join_table=qn(self.field.m2m_db_table()), source_col_name=qn(self.field.m2m_column_name()), target_col_name=qn(self.field.m2m_reverse_name()) ) return manager def __set__(self, instance, value): if instance is None: raise AttributeError, "Manager must be accessed via instance" manager = self.__get__(instance) manager.clear() manager.add(*value) class ForeignKey(RelatedField, Field): empty_strings_allowed = False def __init__(self, to, to_field=None, **kwargs): try: to_name = to._meta.object_name.lower() except AttributeError: # to._meta doesn't exist, so it must be RECURSIVE_RELATIONSHIP_CONSTANT assert isinstance(to, basestring), "ForeignKey(%r) is invalid. First parameter to ForeignKey must be either a model, a model name, or the string %r" % (to, RECURSIVE_RELATIONSHIP_CONSTANT) else: to_field = to_field or to._meta.pk.name kwargs['verbose_name'] = kwargs.get('verbose_name', '') if kwargs.has_key('edit_inline_type'): import warnings warnings.warn("edit_inline_type is deprecated. Use edit_inline instead.") kwargs['edit_inline'] = kwargs.pop('edit_inline_type') kwargs['rel'] = ManyToOneRel(to, to_field, num_in_admin=kwargs.pop('num_in_admin', 3), min_num_in_admin=kwargs.pop('min_num_in_admin', None), max_num_in_admin=kwargs.pop('max_num_in_admin', None), num_extra_on_change=kwargs.pop('num_extra_on_change', 1), edit_inline=kwargs.pop('edit_inline', False), related_name=kwargs.pop('related_name', None), limit_choices_to=kwargs.pop('limit_choices_to', None), lookup_overrides=kwargs.pop('lookup_overrides', None), raw_id_admin=kwargs.pop('raw_id_admin', False)) Field.__init__(self, **kwargs) self.db_index = True def get_attname(self): return '%s_id' % self.name def get_validator_unique_lookup_type(self): return '%s__%s__exact' % (self.name, self.rel.get_related_field().name) def prepare_field_objs_and_params(self, manipulator, name_prefix): params = {'validator_list': self.validator_list[:], 'member_name': name_prefix + self.attname} if self.rel.raw_id_admin: field_objs = self.get_manipulator_field_objs() params['validator_list'].append(curry(manipulator_valid_rel_key, self, manipulator)) else: if self.radio_admin: field_objs = [oldforms.RadioSelectField] params['ul_class'] = get_ul_class(self.radio_admin) else: if self.null: field_objs = [oldforms.NullSelectField] else: field_objs = [oldforms.SelectField] params['choices'] = self.get_choices_default() return field_objs, params def get_manipulator_field_objs(self): rel_field = self.rel.get_related_field() if self.rel.raw_id_admin and not isinstance(rel_field, AutoField): return rel_field.get_manipulator_field_objs() else: return [oldforms.IntegerField] def get_db_prep_save(self, value): if value == '' or value == None: return None else: return self.rel.get_related_field().get_db_prep_save(value) def flatten_data(self, follow, obj=None): if not obj: # In required many-to-one fields with only one available choice, # select that one available choice. Note: For SelectFields # (radio_admin=False), we have to check that the length of choices # is *2*, not 1, because SelectFields always have an initial # "blank" value. Otherwise (radio_admin=True), we check that the # length is 1. if not self.blank and (not self.rel.raw_id_admin or self.choices): choice_list = self.get_choices_default() if self.radio_admin and len(choice_list) == 1: return {self.attname: choice_list[0][0]} if not self.radio_admin and len(choice_list) == 2: return {self.attname: choice_list[1][0]} return Field.flatten_data(self, follow, obj) def contribute_to_class(self, cls, name): super(ForeignKey, self).contribute_to_class(cls, name) setattr(cls, self.name, ReverseSingleRelatedObjectDescriptor(self)) def contribute_to_related_class(self, cls, related): setattr(cls, related.get_accessor_name(), ForeignRelatedObjectsDescriptor(related)) def formfield(self, **kwargs): defaults = {'queryset': self.rel.to._default_manager.all(), 'required': not self.blank, 'label': capfirst(self.verbose_name), 'help_text': self.help_text} defaults.update(kwargs) return forms.ModelChoiceField(**defaults) class OneToOneField(RelatedField, IntegerField): def __init__(self, to, to_field=None, **kwargs): try: to_name = to._meta.object_name.lower() except AttributeError: # to._meta doesn't exist, so it must be RECURSIVE_RELATIONSHIP_CONSTANT assert isinstance(to, basestring), "OneToOneField(%r) is invalid. First parameter to OneToOneField must be either a model, a model name, or the string %r" % (to, RECURSIVE_RELATIONSHIP_CONSTANT) else: to_field = to_field or to._meta.pk.name kwargs['verbose_name'] = kwargs.get('verbose_name', '') if kwargs.has_key('edit_inline_type'): import warnings warnings.warn("edit_inline_type is deprecated. Use edit_inline instead.") kwargs['edit_inline'] = kwargs.pop('edit_inline_type') kwargs['rel'] = OneToOneRel(to, to_field, num_in_admin=kwargs.pop('num_in_admin', 0), edit_inline=kwargs.pop('edit_inline', False), related_name=kwargs.pop('related_name', None), limit_choices_to=kwargs.pop('limit_choices_to', None), lookup_overrides=kwargs.pop('lookup_overrides', None), raw_id_admin=kwargs.pop('raw_id_admin', False)) kwargs['primary_key'] = True IntegerField.__init__(self, **kwargs) self.db_index = True def get_attname(self): return '%s_id' % self.name def get_validator_unique_lookup_type(self): return '%s__%s__exact' % (self.name, self.rel.get_related_field().name) # TODO: Copied from ForeignKey... putting this in RelatedField adversely affects # ManyToManyField. This works for now. def prepare_field_objs_and_params(self, manipulator, name_prefix): params = {'validator_list': self.validator_list[:], 'member_name': name_prefix + self.attname} if self.rel.raw_id_admin: field_objs = self.get_manipulator_field_objs() params['validator_list'].append(curry(manipulator_valid_rel_key, self, manipulator)) else: if self.radio_admin: field_objs = [oldforms.RadioSelectField] params['ul_class'] = get_ul_class(self.radio_admin) else: if self.null: field_objs = [oldforms.NullSelectField] else: field_objs = [oldforms.SelectField] params['choices'] = self.get_choices_default() return field_objs, params def contribute_to_class(self, cls, name): super(OneToOneField, self).contribute_to_class(cls, name) setattr(cls, self.name, ReverseSingleRelatedObjectDescriptor(self)) def contribute_to_related_class(self, cls, related): setattr(cls, related.get_accessor_name(), SingleRelatedObjectDescriptor(related)) if not cls._meta.one_to_one_field: cls._meta.one_to_one_field = self def formfield(self, **kwargs): defaults = {'queryset': self.rel.to._default_manager.all(), 'required': not self.blank, 'label': capfirst(self.verbose_name), 'help_text': self.help_text} defaults.update(kwargs) return forms.ModelChoiceField(**defaults) class ManyToManyField(RelatedField, Field): def __init__(self, to, **kwargs): kwargs['verbose_name'] = kwargs.get('verbose_name', None) kwargs['rel'] = ManyToManyRel(to, num_in_admin=kwargs.pop('num_in_admin', 0), related_name=kwargs.pop('related_name', None), filter_interface=kwargs.pop('filter_interface', None), limit_choices_to=kwargs.pop('limit_choices_to', None), raw_id_admin=kwargs.pop('raw_id_admin', False), symmetrical=kwargs.pop('symmetrical', True)) self.db_table = kwargs.pop('db_table', None) if kwargs["rel"].raw_id_admin: kwargs.setdefault("validator_list", []).append(self.isValidIDList) Field.__init__(self, **kwargs) if self.rel.raw_id_admin: msg = gettext_lazy('Separate multiple IDs with commas.') else: msg = gettext_lazy('Hold down "Control", or "Command" on a Mac, to select more than one.') self.help_text = string_concat(self.help_text, ' ', msg) def get_manipulator_field_objs(self): if self.rel.raw_id_admin: return [oldforms.RawIdAdminField] else: choices = self.get_choices_default() return [curry(oldforms.SelectMultipleField, size=min(max(len(choices), 5), 15), choices=choices)] def get_choices_default(self): return Field.get_choices(self, include_blank=False) def _get_m2m_db_table(self, opts): "Function that can be curried to provide the m2m table name for this relation" if self.db_table: return self.db_table else: return '%s_%s' % (opts.db_table, self.name) def _get_m2m_column_name(self, related): "Function that can be curried to provide the source column name for the m2m table" # If this is an m2m relation to self, avoid the inevitable name clash if related.model == related.parent_model: return 'from_' + related.model._meta.object_name.lower() + '_id' else: return related.model._meta.object_name.lower() + '_id' def _get_m2m_reverse_name(self, related): "Function that can be curried to provide the related column name for the m2m table" # If this is an m2m relation to self, avoid the inevitable name clash if related.model == related.parent_model: return 'to_' + related.parent_model._meta.object_name.lower() + '_id' else: return related.parent_model._meta.object_name.lower() + '_id' def isValidIDList(self, field_data, all_data): "Validates that the value is a valid list of foreign keys" mod = self.rel.to try: pks = map(int, field_data.split(',')) except ValueError: # the CommaSeparatedIntegerField validator will catch this error return objects = mod._default_manager.in_bulk(pks) if len(objects) != len(pks): badkeys = [k for k in pks if k not in objects] raise validators.ValidationError, ngettext("Please enter valid %(self)s IDs. The value %(value)r is invalid.", "Please enter valid %(self)s IDs. The values %(value)r are invalid.", len(badkeys)) % { 'self': self.verbose_name, 'value': len(badkeys) == 1 and badkeys[0] or tuple(badkeys), } def flatten_data(self, follow, obj = None): new_data = {} if obj: instance_ids = [instance._get_pk_val() for instance in getattr(obj, self.name).all()] if self.rel.raw_id_admin: new_data[self.name] = ",".join([str(id) for id in instance_ids]) else: new_data[self.name] = instance_ids else: # In required many-to-many fields with only one available choice, # select that one available choice. if not self.blank and not self.rel.edit_inline and not self.rel.raw_id_admin: choices_list = self.get_choices_default() if len(choices_list) == 1: new_data[self.name] = [choices_list[0][0]] return new_data def contribute_to_class(self, cls, name): super(ManyToManyField, self).contribute_to_class(cls, name) # 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) def contribute_to_related_class(self, cls, related): # m2m relations to self do not have a ManyRelatedObjectsDescriptor, # as it would be redundant - unless the field is non-symmetrical. if related.model != related.parent_model or not self.rel.symmetrical: # Add the descriptor for the m2m relation setattr(cls, related.get_accessor_name(), ManyRelatedObjectsDescriptor(related)) # Set up the accessors for the column names on the m2m table self.m2m_column_name = curry(self._get_m2m_column_name, related) self.m2m_reverse_name = curry(self._get_m2m_reverse_name, related) def set_attributes_from_rel(self): pass def value_from_object(self, obj): "Returns the value of this field in the given model instance." return getattr(obj, self.attname).all() def formfield(self, **kwargs): # If initial is passed in, it's a list of related objects, but the # MultipleChoiceField takes a list of IDs. if kwargs.get('initial') is not None: kwargs['initial'] = [i._get_pk_val() for i in kwargs['initial']] defaults = {'queryset' : self.rel.to._default_manager.all(), 'required': not self.blank, 'label': capfirst(self.verbose_name), 'help_text': self.help_text} defaults.update(kwargs) return forms.ModelMultipleChoiceField(**defaults) class ManyToOneRel(object): def __init__(self, to, field_name, num_in_admin=3, min_num_in_admin=None, max_num_in_admin=None, num_extra_on_change=1, edit_inline=False, related_name=None, limit_choices_to=None, lookup_overrides=None, raw_id_admin=False): try: to._meta except AttributeError: # to._meta doesn't exist, so it must be RECURSIVE_RELATIONSHIP_CONSTANT assert isinstance(to, basestring), "'to' must be either a model, a model name or the string %r" % RECURSIVE_RELATIONSHIP_CONSTANT self.to, self.field_name = to, field_name self.num_in_admin, self.edit_inline = num_in_admin, edit_inline self.min_num_in_admin, self.max_num_in_admin = min_num_in_admin, max_num_in_admin self.num_extra_on_change, self.related_name = num_extra_on_change, related_name if limit_choices_to is None: limit_choices_to = {} self.limit_choices_to = limit_choices_to self.lookup_overrides = lookup_overrides or {} self.raw_id_admin = raw_id_admin self.multiple = True def get_related_field(self): "Returns the Field in the 'to' object to which this relationship is tied." return self.to._meta.get_field(self.field_name) class OneToOneRel(ManyToOneRel): def __init__(self, to, field_name, num_in_admin=0, edit_inline=False, related_name=None, limit_choices_to=None, lookup_overrides=None, raw_id_admin=False): self.to, self.field_name = to, field_name self.num_in_admin, self.edit_inline = num_in_admin, edit_inline self.related_name = related_name if limit_choices_to is None: limit_choices_to = {} self.limit_choices_to = limit_choices_to self.lookup_overrides = lookup_overrides or {} self.raw_id_admin = raw_id_admin self.multiple = False class ManyToManyRel(object): def __init__(self, to, num_in_admin=0, related_name=None, filter_interface=None, limit_choices_to=None, raw_id_admin=False, symmetrical=True): self.to = to self.num_in_admin = num_in_admin self.related_name = related_name self.filter_interface = filter_interface if limit_choices_to is None: limit_choices_to = {} self.limit_choices_to = limit_choices_to self.edit_inline = False self.raw_id_admin = raw_id_admin self.symmetrical = symmetrical self.multiple = True assert not (self.raw_id_admin and self.filter_interface), "ManyToManyRels may not use both raw_id_admin and filter_interface"