-class TreeParentValidator(object):
- """
- constructor takes instance and parent_attr, where instance is the model
- being validated and parent_attr is where to look on that parent for the
- comparison.
- """
- #message = _("A tree element can't be its own parent.")
- code = 'invalid'
-
- def __init__(self, instance, parent_attr=None, message=None, code=None):
- self.instance = instance
- self.parent_attr = parent_attr
- self.static_message = message
- if code is not None:
- self.code = code
-
- def __call__(self, value):
- """
- Validates that the self.instance is not found in the parent tree of
- the node given as value.
- """
- parent = value
-
- while parent:
- comparison=self.get_comparison(parent)
- if comparison == self.instance:
- # using (self.message, code=self.code) results in the admin interface
- # screwing with the error message and making it be 'Enter a valid value'
- raise ValidationError(self.message)
- parent=parent.parent
-
- def get_comparison(self, parent):
- if self.parent_attr and hasattr(parent, self.parent_attr):
- return getattr(parent, self.parent_attr)
-
- return parent
-
- def get_message(self):
- return self.static_message or _(u"A %s can't be its own parent." % self.instance.__class__.__name__)
- message = property(get_message)
-
-class TreePositionValidator(object):
- code = 'invalid'
-
- def __init__(self, parent, slug, obj_class, message=None, code=None):
- self.parent = parent
- self.slug = slug
- self.obj_class = obj_class
- self.static_message = message
-
- if code is not None:
- self.code = code
-
- def __call__(self, value):
- """
- Validates that there is no obj of obj_class with the same position
- as the compared obj (value) but a different id.
- """
- if not isinstance(value, self.obj_class):
- raise ValidationError(_(u"The value must be an instance of %s." % self.obj_class.__name__))
-
- try:
- obj = self.obj_class.objects.get(slug=self.slug, parent=self.parent)
-
- if obj.id != value.id:
- raise ValidationError(self.message)
-
- except self.obj_class.DoesNotExist:
- pass
-
- def get_message(self):
- return self.static_message or _(u"A %s with that path (parent and slug) already exists." % self.obj_class.__name__)
- message = property(get_message)