Fixed #8209: `ModelForm`s now validate unique constraints. Alex Gaynor did... (ea05e61b) · Commits · Dom Sekotill / django

django/forms/models.py

+97 −9

Original line number	Diff line number	Diff line
		@@ -3,9 +3,10 @@ Helper functions for creating Form classes from Django models
		and database field objects.
		"""

		from django.utils.translation import ugettext_lazy as _
		from django.utils.encoding import smart_unicode
		from django.utils.datastructures import SortedDict
		from django.utils.text import get_text_list
		from django.utils.translation import ugettext_lazy as _

		from util import ValidationError, ErrorList
		from forms import BaseForm, get_declared_fields
		@@ -20,6 +21,7 @@ __all__ = (
		'ModelMultipleChoiceField',
		)


		def save_instance(form, instance, fields=None, fail_message='saved',
		commit=True, exclude=None):
		"""
		@@ -202,6 +204,76 @@ class BaseModelForm(BaseForm):
		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
		unique_checks = list(self.instance._meta.unique_together[:])
		form_errors = []

		# Make sure the unique checks apply to actual fields on the ModelForm
		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
		# 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]]

		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 efficiant way to
		# tell if a particular query returns any results.
		if qs.extra(select={'a': 1}).values('a').order_by():
		model_name = self.instance._meta.verbose_name.title()

		# 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([
		_("%(model_name)s with this %(field_label)s already exists.") % \
		{'model_name': model_name, 'field_label': 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(
		_("%(model_name)s with this %(field_label)s already exists.") % \
		{'model_name': model_name, 'field_label': field_labels}
		)

		# Remove the data from the cleaned_data dict since it was invalid
		for field_name in unique_check:
		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):
		"""
		@@ -246,18 +318,26 @@ class BaseModelFormSet(BaseFormSet):
		queryset=None, **kwargs):
		self.queryset = queryset
		defaults = {'data': data, 'files': files, 'auto_id': auto_id, 'prefix': prefix}
		if self.max_num > 0:
		qs = self.get_queryset()[:self.max_num]
		else:
		qs = self.get_queryset()
		defaults['initial'] = [model_to_dict(obj) for obj in qs]
		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:
		return self.queryset
		return self.model._default_manager.get_query_set()
		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."""
		@@ -359,6 +439,14 @@ class BaseInlineFormSet(BaseModelFormSet):
		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

django/utils/itercompat.py

+1 −0

Original line number	Diff line number	Diff line
		@@ -72,3 +72,4 @@ def sorted(in_value):
		out_value = in_value[:]
		out_value.sort()
		return out_value

docs/topics/forms/modelforms.txt

+11 −1

Original line number	Diff line number	Diff line
		@@ -338,6 +338,16 @@ parameter when declaring the form field::
		... class Meta:
		... model = Article

		Overriding the clean() method
		-----------------------------

		You can overide the ``clean()`` method on a model form to provide additional
		validation in the same way you can on a normal form. However, by default the
		``clean()`` method validates the uniqueness of fields that are marked as unique
		on the model, and those marked as unque_together, if you would like to overide
		the ``clean()`` method and maintain the default validation you must call the
		parent class's ``clean()`` method.

		Form inheritance
		----------------

tests/modeltests/model_forms/models.py

+52 −1

Original line number	Diff line number	Diff line
		@@ -117,9 +117,26 @@ class CommaSeparatedInteger(models.Model):
		def __unicode__(self):
		return self.field

		class Product(models.Model):
		slug = models.SlugField(unique=True)

		def __unicode__(self):
		return self.slug

		class Price(models.Model):
		price = models.DecimalField(max_digits=10, decimal_places=2)
		quantity = models.PositiveIntegerField()

		def __unicode__(self):
		return u"%s for %s" % (self.quantity, self.price)

		class Meta:
		unique_together = (('price', 'quantity'),)

		class ArticleStatus(models.Model):
		status = models.CharField(max_length=2, choices=ARTICLE_STATUS_CHAR, blank=True, null=True)


		__test__ = {'API_TESTS': """
		>>> from django import forms
		>>> from django.forms.models import ModelForm, model_to_dict
		@@ -1132,8 +1149,42 @@ u'1,,2'
		>>> f.clean('1')
		u'1'

		# Choices on CharField and IntegerField
		# unique/unique_together validation

		>>> class ProductForm(ModelForm):
		... class Meta:
		... model = Product
		>>> form = ProductForm({'slug': 'teddy-bear-blue'})
		>>> form.is_valid()
		True
		>>> obj = form.save()
		>>> obj
		<Product: teddy-bear-blue>
		>>> form = ProductForm({'slug': 'teddy-bear-blue'})
		>>> form.is_valid()
		False
		>>> form._errors
		{'slug': [u'Product with this Slug already exists.']}
		>>> form = ProductForm({'slug': 'teddy-bear-blue'}, instance=obj)
		>>> form.is_valid()
		True

		# ModelForm test of unique_together constraint
		>>> class PriceForm(ModelForm):
		... class Meta:
		... model = Price
		>>> form = PriceForm({'price': '6.00', 'quantity': '1'})
		>>> form.is_valid()
		True
		>>> form.save()
		<Price: 1 for 6.00>
		>>> form = PriceForm({'price': '6.00', 'quantity': '1'})
		>>> form.is_valid()
		False
		>>> form._errors
		{'__all__': [u'Price with this Price and Quantity already exists.']}

		# Choices on CharField and IntegerField
		>>> class ArticleForm(ModelForm):
		... class Meta:
		... model = Article

tests/modeltests/model_formsets/models.py

+68 −0

Original line number	Diff line number	Diff line
		@@ -73,6 +73,22 @@ class Restaurant(Place):
		def __unicode__(self):
		return self.name

		class Product(models.Model):
		slug = models.SlugField(unique=True)

		def __unicode__(self):
		return self.slug

		class Price(models.Model):
		price = models.DecimalField(max_digits=10, decimal_places=2)
		quantity = models.PositiveIntegerField()

		def __unicode__(self):
		return u"%s for %s" % (self.quantity, self.price)

		class Meta:
		unique_together = (('price', 'quantity'),)

		class MexicanRestaurant(Restaurant):
		serves_tacos = models.BooleanField()

		@@ -553,4 +569,56 @@ True
		>>> type(_get_foreign_key(MexicanRestaurant, Owner))
		<class 'django.db.models.fields.related.ForeignKey'>

		# unique/unique_together validation ###########################################

		>>> FormSet = modelformset_factory(Product, extra=1)
		>>> data = {
		... 'form-TOTAL_FORMS': '1',
		... 'form-INITIAL_FORMS': '0',
		... 'form-0-slug': 'car-red',
		... }
		>>> formset = FormSet(data)
		>>> formset.is_valid()
		True
		>>> formset.save()
		[<Product: car-red>]

		>>> data = {
		... 'form-TOTAL_FORMS': '1',
		... 'form-INITIAL_FORMS': '0',
		... 'form-0-slug': 'car-red',
		... }
		>>> formset = FormSet(data)
		>>> formset.is_valid()
		False
		>>> formset.errors
		[{'slug': [u'Product with this Slug already exists.']}]

		# unique_together

		>>> FormSet = modelformset_factory(Price, extra=1)
		>>> data = {
		... 'form-TOTAL_FORMS': '1',
		... 'form-INITIAL_FORMS': '0',
		... 'form-0-price': u'12.00',
		... 'form-0-quantity': '1',
		... }
		>>> formset = FormSet(data)
		>>> formset.is_valid()
		True
		>>> formset.save()
		[<Price: 1 for 12.00>]

		>>> data = {
		... 'form-TOTAL_FORMS': '1',
		... 'form-INITIAL_FORMS': '0',
		... 'form-0-price': u'12.00',
		... 'form-0-quantity': '1',
		... }
		>>> formset = FormSet(data)
		>>> formset.is_valid()
		False
		>>> formset.errors
		[{'__all__': [u'Price with this Price and Quantity already exists.']}]

		"""}