--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/forms/models.py Tue Oct 14 16:00:59 2008 +0000
@@ -0,0 +1,698 @@
+"""
+Helper functions for creating Form classes from Django models
+and database field objects.
+"""
+
+from django.utils.encoding import smart_unicode
+from django.utils.datastructures import SortedDict
+from django.utils.text import get_text_list, capfirst
+from django.utils.translation import ugettext_lazy as _
+
+from util import ValidationError, ErrorList
+from forms import BaseForm, get_declared_fields
+from fields import Field, ChoiceField, IntegerField, EMPTY_VALUES
+from widgets import Select, SelectMultiple, HiddenInput, MultipleHiddenInput
+from widgets import media_property
+from formsets import BaseFormSet, formset_factory, DELETION_FIELD_NAME
+
+try:
+ set
+except NameError:
+ from sets import Set as set # Python 2.3 fallback
+
+__all__ = (
+ 'ModelForm', 'BaseModelForm', 'model_to_dict', 'fields_for_model',
+ 'save_instance', 'form_for_fields', 'ModelChoiceField',
+ 'ModelMultipleChoiceField',
+)
+
+
+def save_instance(form, instance, fields=None, fail_message='saved',
+ commit=True, exclude=None):
+ """
+ Saves bound Form ``form``'s cleaned_data into model instance ``instance``.
+
+ If commit=True, then the changes to ``instance`` will be saved to the
+ database. Returns ``instance``.
+ """
+ from django.db import models
+ opts = instance._meta
+ if form.errors:
+ raise ValueError("The %s could not be %s because the data didn't"
+ " validate." % (opts.object_name, fail_message))
+ cleaned_data = form.cleaned_data
+ for f in opts.fields:
+ if not f.editable or isinstance(f, models.AutoField) \
+ or not f.name in cleaned_data:
+ continue
+ if fields and f.name not in fields:
+ continue
+ if exclude and f.name in exclude:
+ continue
+ f.save_form_data(instance, cleaned_data[f.name])
+ # Wrap up the saving of m2m data as a function.
+ def save_m2m():
+ opts = instance._meta
+ cleaned_data = form.cleaned_data
+ for f in opts.many_to_many:
+ if fields and f.name not in fields:
+ continue
+ if f.name in cleaned_data:
+ f.save_form_data(instance, cleaned_data[f.name])
+ if commit:
+ # If we are committing, save the instance and the m2m data immediately.
+ instance.save()
+ save_m2m()
+ else:
+ # We're not committing. Add a method to the form to allow deferred
+ # saving of m2m data.
+ form.save_m2m = save_m2m
+ return instance
+
+def make_model_save(model, fields, fail_message):
+ """Returns the save() method for a Form."""
+ def save(self, commit=True):
+ return save_instance(self, model(), fields, fail_message, commit)
+ return save
+
+def make_instance_save(instance, fields, fail_message):
+ """Returns the save() method for a Form."""
+ def save(self, commit=True):
+ return save_instance(self, instance, fields, fail_message, commit)
+ return save
+
+def form_for_fields(field_list):
+ """
+ Returns a Form class for the given list of Django database field instances.
+ """
+ fields = SortedDict([(f.name, f.formfield())
+ for f in field_list if f.editable])
+ return type('FormForFields', (BaseForm,), {'base_fields': fields})
+
+
+# ModelForms #################################################################
+
+def model_to_dict(instance, fields=None, exclude=None):
+ """
+ Returns a dict containing the data in ``instance`` suitable for passing as
+ a Form's ``initial`` keyword argument.
+
+ ``fields`` is an optional list of field names. If provided, only the named
+ fields will be included in the returned dict.
+
+ ``exclude`` is an optional list of field names. If provided, the named
+ fields will be excluded from the returned dict, even if they are listed in
+ the ``fields`` argument.
+ """
+ # avoid a circular import
+ from django.db.models.fields.related import ManyToManyField, OneToOneField
+ opts = instance._meta
+ data = {}
+ for f in opts.fields + opts.many_to_many:
+ if not f.editable:
+ continue
+ if fields and not f.name in fields:
+ continue
+ if exclude and f.name in exclude:
+ continue
+ if isinstance(f, ManyToManyField):
+ # If the object doesn't have a primry key yet, just use an empty
+ # list for its m2m fields. Calling f.value_from_object will raise
+ # an exception.
+ if instance.pk is None:
+ data[f.name] = []
+ else:
+ # MultipleChoiceWidget needs a list of pks, not object instances.
+ data[f.name] = [obj.pk for obj in f.value_from_object(instance)]
+ else:
+ data[f.name] = f.value_from_object(instance)
+ return data
+
+def fields_for_model(model, fields=None, exclude=None, formfield_callback=lambda f: f.formfield()):
+ """
+ Returns a ``SortedDict`` containing form fields for the given model.
+
+ ``fields`` is an optional list of field names. If provided, only the named
+ fields will be included in the returned fields.
+
+ ``exclude`` is an optional list of field names. If provided, the named
+ fields will be excluded from the returned fields, even if they are listed
+ in the ``fields`` argument.
+ """
+ # TODO: if fields is provided, it would be nice to return fields in that order
+ field_list = []
+ opts = model._meta
+ for f in opts.fields + opts.many_to_many:
+ if not f.editable:
+ continue
+ if fields and not f.name in fields:
+ continue
+ if exclude and f.name in exclude:
+ continue
+ formfield = formfield_callback(f)
+ if formfield:
+ field_list.append((f.name, formfield))
+ return SortedDict(field_list)
+
+class ModelFormOptions(object):
+ def __init__(self, options=None):
+ self.model = getattr(options, 'model', None)
+ self.fields = getattr(options, 'fields', None)
+ self.exclude = getattr(options, 'exclude', None)
+
+
+class ModelFormMetaclass(type):
+ def __new__(cls, name, bases, attrs):
+ formfield_callback = attrs.pop('formfield_callback',
+ lambda f: f.formfield())
+ try:
+ parents = [b for b in bases if issubclass(b, ModelForm)]
+ except NameError:
+ # We are defining ModelForm itself.
+ parents = None
+ declared_fields = get_declared_fields(bases, attrs, False)
+ new_class = super(ModelFormMetaclass, cls).__new__(cls, name, bases,
+ attrs)
+ if not parents:
+ return new_class
+
+ if 'media' not in attrs:
+ new_class.media = media_property(new_class)
+ opts = new_class._meta = ModelFormOptions(getattr(new_class, 'Meta', None))
+ if opts.model:
+ # If a model is defined, extract form fields from it.
+ fields = fields_for_model(opts.model, opts.fields,
+ opts.exclude, formfield_callback)
+ # Override default model fields with any custom declared ones
+ # (plus, include all the other declared fields).
+ fields.update(declared_fields)
+ else:
+ fields = declared_fields
+ new_class.declared_fields = declared_fields
+ new_class.base_fields = fields
+ return new_class
+
+class BaseModelForm(BaseForm):
+ def __init__(self, data=None, files=None, auto_id='id_%s', prefix=None,
+ initial=None, error_class=ErrorList, label_suffix=':',
+ empty_permitted=False, instance=None):
+ opts = self._meta
+ if instance is None:
+ # if we didn't get an instance, instantiate a new one
+ self.instance = opts.model()
+ object_data = {}
+ else:
+ self.instance = instance
+ object_data = model_to_dict(instance, opts.fields, opts.exclude)
+ # if initial was provided, it should override the values from instance
+ if initial is not None:
+ object_data.update(initial)
+ super(BaseModelForm, self).__init__(data, files, auto_id, prefix, object_data,
+ error_class, label_suffix, empty_permitted)
+ def clean(self):
+ self.validate_unique()
+ return self.cleaned_data
+
+ def validate_unique(self):
+ from django.db.models.fields import FieldDoesNotExist
+
+ # Gather a list of checks to perform. Since this is a ModelForm, some
+ # fields may have been excluded; we can't perform a unique check on a
+ # form that is missing fields involved in that check.
+ unique_checks = []
+ for check in self.instance._meta.unique_together[:]:
+ fields_on_form = [field for field in check if field in self.fields]
+ if len(fields_on_form) == len(check):
+ unique_checks.append(check)
+
+ form_errors = []
+
+ # Gather a list of checks for fields declared as unique and add them to
+ # the list of checks. Again, skip fields not on the form.
+ for name, field in self.fields.items():
+ try:
+ f = self.instance._meta.get_field_by_name(name)[0]
+ except FieldDoesNotExist:
+ # This is an extra field that's not on the ModelForm, ignore it
+ continue
+ # MySQL can't handle ... WHERE pk IS NULL, so make sure we
+ # don't generate queries of that form.
+ is_null_pk = f.primary_key and self.cleaned_data[name] is None
+ if name in self.cleaned_data and f.unique and not is_null_pk:
+ unique_checks.append((name,))
+
+ # Don't run unique checks on fields that already have an error.
+ unique_checks = [check for check in unique_checks if not [x in self._errors for x in check if x in self._errors]]
+
+ bad_fields = set()
+ for unique_check in unique_checks:
+ # Try to look up an existing object with the same values as this
+ # object's values for all the unique field.
+
+ lookup_kwargs = {}
+ for field_name in unique_check:
+ lookup_kwargs[field_name] = self.cleaned_data[field_name]
+
+ qs = self.instance.__class__._default_manager.filter(**lookup_kwargs)
+
+ # Exclude the current object from the query if we are editing an
+ # instance (as opposed to creating a new one)
+ if self.instance.pk is not None:
+ qs = qs.exclude(pk=self.instance.pk)
+
+ # This cute trick with extra/values is the most efficient way to
+ # tell if a particular query returns any results.
+ if qs.extra(select={'a': 1}).values('a').order_by():
+ model_name = capfirst(self.instance._meta.verbose_name)
+
+ # A unique field
+ if len(unique_check) == 1:
+ field_name = unique_check[0]
+ field_label = self.fields[field_name].label
+ # Insert the error into the error dict, very sneaky
+ self._errors[field_name] = ErrorList([
+ _(u"%(model_name)s with this %(field_label)s already exists.") % \
+ {'model_name': unicode(model_name),
+ 'field_label': unicode(field_label)}
+ ])
+ # unique_together
+ else:
+ field_labels = [self.fields[field_name].label for field_name in unique_check]
+ field_labels = get_text_list(field_labels, _('and'))
+ form_errors.append(
+ _(u"%(model_name)s with this %(field_label)s already exists.") % \
+ {'model_name': unicode(model_name),
+ 'field_label': unicode(field_labels)}
+ )
+
+ # Mark these fields as needing to be removed from cleaned data
+ # later.
+ for field_name in unique_check:
+ bad_fields.add(field_name)
+
+ for field_name in bad_fields:
+ del self.cleaned_data[field_name]
+ if form_errors:
+ # Raise the unique together errors since they are considered
+ # form-wide.
+ raise ValidationError(form_errors)
+
+ def save(self, commit=True):
+ """
+ Saves this ``form``'s cleaned_data into model instance
+ ``self.instance``.
+
+ If commit=True, then the changes to ``instance`` will be saved to the
+ database. Returns ``instance``.
+ """
+ if self.instance.pk is None:
+ fail_message = 'created'
+ else:
+ fail_message = 'changed'
+ return save_instance(self, self.instance, self._meta.fields, fail_message, commit)
+
+class ModelForm(BaseModelForm):
+ __metaclass__ = ModelFormMetaclass
+
+def modelform_factory(model, form=ModelForm, fields=None, exclude=None,
+ formfield_callback=lambda f: f.formfield()):
+ # HACK: we should be able to construct a ModelForm without creating
+ # and passing in a temporary inner class
+ class Meta:
+ pass
+ setattr(Meta, 'model', model)
+ setattr(Meta, 'fields', fields)
+ setattr(Meta, 'exclude', exclude)
+ class_name = model.__name__ + 'Form'
+ return ModelFormMetaclass(class_name, (form,), {'Meta': Meta,
+ 'formfield_callback': formfield_callback})
+
+
+# ModelFormSets ##############################################################
+
+class BaseModelFormSet(BaseFormSet):
+ """
+ A ``FormSet`` for editing a queryset and/or adding new objects to it.
+ """
+ model = None
+
+ def __init__(self, data=None, files=None, auto_id='id_%s', prefix=None,
+ queryset=None, **kwargs):
+ self.queryset = queryset
+ defaults = {'data': data, 'files': files, 'auto_id': auto_id, 'prefix': prefix}
+ defaults['initial'] = [model_to_dict(obj) for obj in self.get_queryset()]
+ defaults.update(kwargs)
+ super(BaseModelFormSet, self).__init__(**defaults)
+
+ def _construct_form(self, i, **kwargs):
+ if i < self._initial_form_count:
+ kwargs['instance'] = self.get_queryset()[i]
+ return super(BaseModelFormSet, self)._construct_form(i, **kwargs)
+
+ def get_queryset(self):
+ if not hasattr(self, '_queryset'):
+ if self.queryset is not None:
+ qs = self.queryset
+ else:
+ qs = self.model._default_manager.get_query_set()
+ if self.max_num > 0:
+ self._queryset = qs[:self.max_num]
+ else:
+ self._queryset = qs
+ return self._queryset
+
+ def save_new(self, form, commit=True):
+ """Saves and returns a new model instance for the given form."""
+ return save_instance(form, self.model(), exclude=[self._pk_field.name], commit=commit)
+
+ def save_existing(self, form, instance, commit=True):
+ """Saves and returns an existing model instance for the given form."""
+ return save_instance(form, instance, exclude=[self._pk_field.name], commit=commit)
+
+ def save(self, commit=True):
+ """Saves model instances for every form, adding and changing instances
+ as necessary, and returns the list of instances.
+ """
+ if not commit:
+ self.saved_forms = []
+ def save_m2m():
+ for form in self.saved_forms:
+ form.save_m2m()
+ self.save_m2m = save_m2m
+ return self.save_existing_objects(commit) + self.save_new_objects(commit)
+
+ def save_existing_objects(self, commit=True):
+ self.changed_objects = []
+ self.deleted_objects = []
+ if not self.get_queryset():
+ return []
+
+ # Put the objects from self.get_queryset into a dict so they are easy to lookup by pk
+ existing_objects = {}
+ for obj in self.get_queryset():
+ existing_objects[obj.pk] = obj
+ saved_instances = []
+ for form in self.initial_forms:
+ obj = existing_objects[form.cleaned_data[self._pk_field.name]]
+ if self.can_delete and form.cleaned_data[DELETION_FIELD_NAME]:
+ self.deleted_objects.append(obj)
+ obj.delete()
+ else:
+ if form.changed_data:
+ self.changed_objects.append((obj, form.changed_data))
+ saved_instances.append(self.save_existing(form, obj, commit=commit))
+ if not commit:
+ self.saved_forms.append(form)
+ return saved_instances
+
+ def save_new_objects(self, commit=True):
+ self.new_objects = []
+ for form in self.extra_forms:
+ if not form.has_changed():
+ continue
+ # If someone has marked an add form for deletion, don't save the
+ # object.
+ if self.can_delete and form.cleaned_data[DELETION_FIELD_NAME]:
+ continue
+ self.new_objects.append(self.save_new(form, commit=commit))
+ if not commit:
+ self.saved_forms.append(form)
+ return self.new_objects
+
+ def add_fields(self, form, index):
+ """Add a hidden field for the object's primary key."""
+ from django.db.models import AutoField
+ self._pk_field = pk = self.model._meta.pk
+ if pk.auto_created or isinstance(pk, AutoField):
+ form.fields[self._pk_field.name] = IntegerField(required=False, widget=HiddenInput)
+ super(BaseModelFormSet, self).add_fields(form, index)
+
+def modelformset_factory(model, form=ModelForm, formfield_callback=lambda f: f.formfield(),
+ formset=BaseModelFormSet,
+ extra=1, can_delete=False, can_order=False,
+ max_num=0, fields=None, exclude=None):
+ """
+ Returns a FormSet class for the given Django model class.
+ """
+ form = modelform_factory(model, form=form, fields=fields, exclude=exclude,
+ formfield_callback=formfield_callback)
+ FormSet = formset_factory(form, formset, extra=extra, max_num=max_num,
+ can_order=can_order, can_delete=can_delete)
+ FormSet.model = model
+ return FormSet
+
+
+# InlineFormSets #############################################################
+
+class BaseInlineFormSet(BaseModelFormSet):
+ """A formset for child objects related to a parent."""
+ def __init__(self, data=None, files=None, instance=None,
+ save_as_new=False, prefix=None):
+ from django.db.models.fields.related import RelatedObject
+ self.instance = instance
+ self.save_as_new = save_as_new
+ # is there a better way to get the object descriptor?
+ self.rel_name = RelatedObject(self.fk.rel.to, self.model, self.fk).get_accessor_name()
+ super(BaseInlineFormSet, self).__init__(data, files, prefix=prefix or self.rel_name)
+
+ def _construct_forms(self):
+ if self.save_as_new:
+ self._total_form_count = self._initial_form_count
+ self._initial_form_count = 0
+ super(BaseInlineFormSet, self)._construct_forms()
+
+ def _construct_form(self, i, **kwargs):
+ form = super(BaseInlineFormSet, self)._construct_form(i, **kwargs)
+ if self.save_as_new:
+ # Remove the primary key from the form's data, we are only
+ # creating new instances
+ form.data[form.add_prefix(self._pk_field.name)] = None
+ return form
+
+ def get_queryset(self):
+ """
+ Returns this FormSet's queryset, but restricted to children of
+ self.instance
+ """
+ kwargs = {self.fk.name: self.instance}
+ return self.model._default_manager.filter(**kwargs)
+
+ def save_new(self, form, commit=True):
+ kwargs = {self.fk.get_attname(): self.instance.pk}
+ new_obj = self.model(**kwargs)
+ return save_instance(form, new_obj, exclude=[self._pk_field.name], commit=commit)
+
+ def add_fields(self, form, index):
+ super(BaseInlineFormSet, self).add_fields(form, index)
+ if self._pk_field == self.fk:
+ form.fields[self._pk_field.name] = IntegerField(required=False, widget=HiddenInput)
+
+def _get_foreign_key(parent_model, model, fk_name=None):
+ """
+ Finds and returns the ForeignKey from model to parent if there is one.
+ If fk_name is provided, assume it is the name of the ForeignKey field.
+ """
+ # avoid circular import
+ from django.db.models import ForeignKey
+ opts = model._meta
+ if fk_name:
+ fks_to_parent = [f for f in opts.fields if f.name == fk_name]
+ if len(fks_to_parent) == 1:
+ fk = fks_to_parent[0]
+ if not isinstance(fk, ForeignKey) or \
+ (fk.rel.to != parent_model and
+ fk.rel.to not in parent_model._meta.get_parent_list()):
+ raise Exception("fk_name '%s' is not a ForeignKey to %s" % (fk_name, parent_model))
+ elif len(fks_to_parent) == 0:
+ raise Exception("%s has no field named '%s'" % (model, fk_name))
+ else:
+ # Try to discover what the ForeignKey from model to parent_model is
+ fks_to_parent = [
+ f for f in opts.fields
+ if isinstance(f, ForeignKey)
+ and (f.rel.to == parent_model
+ or f.rel.to in parent_model._meta.get_parent_list())
+ ]
+ if len(fks_to_parent) == 1:
+ fk = fks_to_parent[0]
+ elif len(fks_to_parent) == 0:
+ raise Exception("%s has no ForeignKey to %s" % (model, parent_model))
+ else:
+ raise Exception("%s has more than 1 ForeignKey to %s" % (model, parent_model))
+ return fk
+
+
+def inlineformset_factory(parent_model, model, form=ModelForm,
+ formset=BaseInlineFormSet, fk_name=None,
+ fields=None, exclude=None,
+ extra=3, can_order=False, can_delete=True, max_num=0,
+ formfield_callback=lambda f: f.formfield()):
+ """
+ Returns an ``InlineFormSet`` for the given kwargs.
+
+ You must provide ``fk_name`` if ``model`` has more than one ``ForeignKey``
+ to ``parent_model``.
+ """
+ fk = _get_foreign_key(parent_model, model, fk_name=fk_name)
+ # enforce a max_num=1 when the foreign key to the parent model is unique.
+ if fk.unique:
+ max_num = 1
+ if exclude is not None:
+ exclude = list(exclude)
+ exclude.append(fk.name)
+ else:
+ exclude = [fk.name]
+ kwargs = {
+ 'form': form,
+ 'formfield_callback': formfield_callback,
+ 'formset': formset,
+ 'extra': extra,
+ 'can_delete': can_delete,
+ 'can_order': can_order,
+ 'fields': fields,
+ 'exclude': exclude,
+ 'max_num': max_num,
+ }
+ FormSet = modelformset_factory(model, **kwargs)
+ FormSet.fk = fk
+ return FormSet
+
+
+# Fields #####################################################################
+
+class ModelChoiceIterator(object):
+ def __init__(self, field):
+ self.field = field
+ self.queryset = field.queryset
+
+ def __iter__(self):
+ if self.field.empty_label is not None:
+ yield (u"", self.field.empty_label)
+ if self.field.cache_choices:
+ if self.field.choice_cache is None:
+ self.field.choice_cache = [
+ self.choice(obj) for obj in self.queryset.all()
+ ]
+ for choice in self.field.choice_cache:
+ yield choice
+ else:
+ for obj in self.queryset.all():
+ yield self.choice(obj)
+
+ def choice(self, obj):
+ if self.field.to_field_name:
+ # FIXME: The try..except shouldn't be necessary here. But this is
+ # going in just before 1.0, so I want to be careful. Will check it
+ # out later.
+ try:
+ key = getattr(obj, self.field.to_field_name).pk
+ except AttributeError:
+ key = getattr(obj, self.field.to_field_name)
+ else:
+ key = obj.pk
+ return (key, self.field.label_from_instance(obj))
+
+
+class ModelChoiceField(ChoiceField):
+ """A ChoiceField whose choices are a model QuerySet."""
+ # This class is a subclass of ChoiceField for purity, but it doesn't
+ # actually use any of ChoiceField's implementation.
+ default_error_messages = {
+ 'invalid_choice': _(u'Select a valid choice. That choice is not one of'
+ u' the available choices.'),
+ }
+
+ def __init__(self, queryset, empty_label=u"---------", cache_choices=False,
+ required=True, widget=None, label=None, initial=None,
+ help_text=None, to_field_name=None, *args, **kwargs):
+ self.empty_label = empty_label
+ self.cache_choices = cache_choices
+
+ # Call Field instead of ChoiceField __init__() because we don't need
+ # ChoiceField.__init__().
+ Field.__init__(self, required, widget, label, initial, help_text,
+ *args, **kwargs)
+ self.queryset = queryset
+ self.choice_cache = None
+ self.to_field_name = to_field_name
+
+ def _get_queryset(self):
+ return self._queryset
+
+ def _set_queryset(self, queryset):
+ self._queryset = queryset
+ self.widget.choices = self.choices
+
+ queryset = property(_get_queryset, _set_queryset)
+
+ # this method will be used to create object labels by the QuerySetIterator.
+ # Override it to customize the label.
+ def label_from_instance(self, obj):
+ """
+ This method is used to convert objects into strings; it's used to
+ generate the labels for the choices presented by this object. Subclasses
+ can override this method to customize the display of the choices.
+ """
+ return smart_unicode(obj)
+
+ def _get_choices(self):
+ # If self._choices is set, then somebody must have manually set
+ # the property self.choices. In this case, just return self._choices.
+ if hasattr(self, '_choices'):
+ return self._choices
+
+ # Otherwise, execute the QuerySet in self.queryset to determine the
+ # choices dynamically. Return a fresh QuerySetIterator that has not been
+ # consumed. Note that we're instantiating a new QuerySetIterator *each*
+ # time _get_choices() is called (and, thus, each time self.choices is
+ # accessed) so that we can ensure the QuerySet has not been consumed. This
+ # construct might look complicated but it allows for lazy evaluation of
+ # the queryset.
+ return ModelChoiceIterator(self)
+
+ choices = property(_get_choices, ChoiceField._set_choices)
+
+ def clean(self, value):
+ Field.clean(self, value)
+ if value in EMPTY_VALUES:
+ return None
+ try:
+ key = self.to_field_name or 'pk'
+ value = self.queryset.get(**{key: value})
+ except self.queryset.model.DoesNotExist:
+ raise ValidationError(self.error_messages['invalid_choice'])
+ return value
+
+class ModelMultipleChoiceField(ModelChoiceField):
+ """A MultipleChoiceField whose choices are a model QuerySet."""
+ widget = SelectMultiple
+ hidden_widget = MultipleHiddenInput
+ default_error_messages = {
+ 'list': _(u'Enter a list of values.'),
+ 'invalid_choice': _(u'Select a valid choice. %s is not one of the'
+ u' available choices.'),
+ }
+
+ def __init__(self, queryset, cache_choices=False, required=True,
+ widget=None, label=None, initial=None,
+ help_text=None, *args, **kwargs):
+ super(ModelMultipleChoiceField, self).__init__(queryset, None,
+ cache_choices, required, widget, label, initial, help_text,
+ *args, **kwargs)
+
+ def clean(self, value):
+ if self.required and not value:
+ raise ValidationError(self.error_messages['required'])
+ elif not self.required and not value:
+ return []
+ if not isinstance(value, (list, tuple)):
+ raise ValidationError(self.error_messages['list'])
+ final_values = []
+ for val in value:
+ try:
+ obj = self.queryset.get(pk=val)
+ except self.queryset.model.DoesNotExist:
+ raise ValidationError(self.error_messages['invalid_choice'] % val)
+ else:
+ final_values.append(obj)
+ return final_values