def validate(self, value, model_instance):
if self.has_choices_callback:
if self.rel.parent_link:
return
if value is None:
return
data = model_to_dict(model_instance)
for field in model_instance._meta.fields:
try:
data[field.name] = getattr(model_instance, field.name)
except field.rel.to.DoesNotExist:
pass
if model_instance.id:
for m2m in model_instance._meta.many_to_many:
data[m2m.name] = getattr(model_instance, m2m.name).all()
qs = self.rel.to._default_manager.filter(**{self.rel.field_name:value})
qs = qs.complex_filter(self.rel.limit_choices_to)
dcqs = self._invoke_choices_callback(model_instance, qs, data)
# If a tuple is provided we must build
# a new Queryset by combining group's ones
if isinstance(dcqs, tuple):
qs = qs and unionize_querysets(q[1] for q in dcqs)
else:
qs = dcqs
if not qs.exists():
raise exceptions.ValidationError(self.error_messages['invalid'] % {
'model': self.rel.to._meta.verbose_name, 'pk': value})
else:
super(DynamicChoicesForeignKey, self).validate(value, model_instance)
def _set_queryset(self, queryset):
self._original_queryset = queryset
self._groups = None
if self._instance and isinstance(queryset, DynamicChoicesQueryset):
queryset = queryset.filter_for_instance(self._instance, self._data)
if isinstance(queryset, tuple):
self._groups = queryset
queryset = unionize_querysets(q[1] for q in queryset)
self._queryset = queryset
self.widget.choices = self.choices
