Genericized penfield's migrations to allow for variations in the PHILO_PERSON_MODULE...
[philo.git] / models / fields.py
index 9483516..74a0525 100644 (file)
@@ -7,7 +7,7 @@ from philo.signals import entity_class_prepared
 from philo.validators import TemplateValidator, json_validator
 
 
-__all__ = ('AttributeField', 'RelationshipField')
+__all__ = ('JSONAttribute', 'ForeignKeyAttribute', 'ManyToManyAttribute')
 
 
 class EntityProxyField(object):
@@ -47,9 +47,9 @@ class AttributeFieldDescriptor(object):
        
        def __get__(self, instance, owner):
                if instance:
-                       if self.field.key in instance._added_attribute_registry:
-                               return instance._added_attribute_registry[self.field.key]
-                       if self.field.key in instance._removed_attribute_registry:
+                       if self.field in instance._added_attribute_registry:
+                               return instance._added_attribute_registry[self.field]
+                       if self.field in instance._removed_attribute_registry:
                                return None
                        try:
                                return instance.attributes[self.field.key]
@@ -59,18 +59,61 @@ class AttributeFieldDescriptor(object):
                        raise AttributeError('The \'%s\' attribute can only be accessed from %s instances.' % (self.field.name, owner.__name__))
        
        def __set__(self, instance, value):
-               if self.field.key in instance._removed_attribute_registry:
-                       instance._removed_attribute_registry.remove(self.field.key)
-               instance._added_attribute_registry[self.field.key] = value
+               raise NotImplementedError('AttributeFieldDescriptor subclasses must implement a __set__ method.')
        
        def __delete__(self, instance):
-               if self.field.key in instance._added_attribute_registry:
-                       del instance._added_attribute_registry[self.field.key]
-               instance._removed_attribute_registry.append(self.field.key)
+               if self.field in instance._added_attribute_registry:
+                       del instance._added_attribute_registry[self.field]
+               instance._removed_attribute_registry.append(self.field)
+
+
+class JSONAttributeDescriptor(AttributeFieldDescriptor):
+       def __set__(self, instance, value):
+               if self.field in instance._removed_attribute_registry:
+                       instance._removed_attribute_registry.remove(self.field)
+               instance._added_attribute_registry[self.field] = value
+
+
+class ForeignKeyAttributeDescriptor(AttributeFieldDescriptor):
+       def __set__(self, instance, value):
+               if isinstance(value, (models.Model, type(None))):
+                       if self.field in instance._removed_attribute_registry:
+                               instance._removed_attribute_registry.remove(self.field)
+                       instance._added_attribute_registry[self.field] = value
+               else:
+                       raise AttributeError('The \'%s\' attribute can only be set using existing Model objects.' % self.field.name)
+
+
+class ManyToManyAttributeDescriptor(AttributeFieldDescriptor):
+       def __set__(self, instance, value):
+               if isinstance(value, models.QuerySet):
+                       if self.field in instance._removed_attribute_registry:
+                               instance._removed_attribute_registry.remove(self.field)
+                       instance._added_attribute_registry[self.field] = value
+               else:
+                       raise AttributeError('The \'%s\' attribute can only be set to a QuerySet.' % self.field.name)
 
 
 class AttributeField(EntityProxyField):
-       descriptor_class = AttributeFieldDescriptor
+       def contribute_to_class(self, cls, name):
+               super(AttributeField, self).contribute_to_class(cls, name)
+               if self.key is None:
+                       self.key = name
+       
+       def set_attribute_value(self, attribute, value, value_class):
+               if not isinstance(attribute.value, value_class):
+                       if isinstance(attribute.value, models.Model):
+                               attribute.value.delete()
+                       new_value = value_class()
+               else:
+                       new_value = attribute.value
+               new_value.value = value
+               new_value.save()
+               attribute.value = new_value
+
+
+class JSONAttribute(AttributeField):
+       descriptor_class = JSONAttributeDescriptor
        
        def __init__(self, field_template=None, key=None, **kwargs):
                super(AttributeField, self).__init__(**kwargs)
@@ -79,72 +122,65 @@ class AttributeField(EntityProxyField):
                        field_template = models.CharField(max_length=255)
                self.field_template = field_template
        
-       def contribute_to_class(self, cls, name):
-               super(AttributeField, self).contribute_to_class(cls, name)
-               if self.key is None:
-                       self.key = name
-       
        def formfield(self, **kwargs):
                defaults = {'required': False, 'label': capfirst(self.verbose_name), 'help_text': self.help_text}
                defaults.update(kwargs)
                return self.field_template.formfield(**defaults)
-
-
-class RelationshipFieldDescriptor(object):
-       def __init__(self, field):
-               self.field = field
-       
-       def __get__(self, instance, owner):
-               if instance:
-                       if self.field.key in instance._added_relationship_registry:
-                               return instance._added_relationship_registry[self.field.key]
-                       if self.field.key in instance._removed_relationship_registry:
-                               return None
-                       try:
-                               return instance.relationships[self.field.key]
-                       except KeyError:
-                               return None
-               else:
-                       raise AttributeError('The \'%s\' attribute can only be accessed from %s instances.' % (self.field.name, owner.__name__))
        
-       def __set__(self, instance, value):
-               if isinstance(value, (models.Model, type(None))):
-                       if self.field.key in instance._removed_relationship_registry:
-                               instance._removed_relationship_registry.remove(self.field.key)
-                       instance._added_relationship_registry[self.field.key] = value
-               else:
-                       raise AttributeError('The \'%s\' attribute can only be set using existing Model objects.' % self.field.name)
+       def value_from_object(self, obj):
+               try:
+                       return getattr(obj, self.attname)
+               except AttributeError:
+                       return None
        
-       def __delete__(self, instance):
-               if self.field.key in instance._added_relationship_registry:
-                       del instance._added_relationship_registry[self.field.key]
-               instance._removed_relationship_registry.append(self.field.key)
+       def set_attribute_value(self, attribute, value, value_class=None):
+               if value_class is None:
+                       from philo.models.base import JSONValue
+                       value_class = JSONValue
+               super(JSONAttribute, self).set_attribute_value(attribute, value, value_class)
 
 
-class RelationshipField(EntityProxyField):
-       descriptor_class = RelationshipFieldDescriptor
+class ForeignKeyAttribute(AttributeField):
+       descriptor_class = ForeignKeyAttributeDescriptor
        
        def __init__(self, model, limit_choices_to=None, key=None, **kwargs):
-               super(RelationshipField, self).__init__(**kwargs)
+               super(ForeignKeyAttribute, self).__init__(**kwargs)
                self.key = key
                self.model = model
                if limit_choices_to is None:
                        limit_choices_to = {}
                self.limit_choices_to = limit_choices_to
        
-       def contribute_to_class(self, cls, name):
-               super(RelationshipField, self).contribute_to_class(cls, name)
-               if self.key is None:
-                       self.key = name
-       
        def formfield(self, form_class=forms.ModelChoiceField, **kwargs):
                defaults = {'required': False, 'label': capfirst(self.verbose_name), 'help_text': self.help_text}
                defaults.update(kwargs)
                return form_class(self.model._default_manager.complex_filter(self.limit_choices_to), **defaults)
        
        def value_from_object(self, obj):
-               relobj = super(RelationshipField, self).value_from_object(obj)
+               try:
+                       relobj = super(ForeignKeyAttribute, self).value_from_object(obj)
+               except AttributeError:
+                       return None
                return getattr(relobj, 'pk', None)
+       
+       def set_attribute_value(self, attribute, value, value_class=None):
+               if value_class is None:
+                       from philo.models.base import ForeignKeyValue
+                       value_class = ForeignKeyValue
+               super(ForeignKeyAttribute, self).set_attribute_value(attribute, value, value_class)
+
+
+class ManyToManyAttribute(ForeignKeyAttribute):
+       descriptor_class = ManyToManyAttributeDescriptor
+       
+       def formfield(self, form_class=forms.ModelMultipleChoiceField, **kwargs):
+               return super(ManyToManyAttribute, self).formfield(form_class, **kwargs)
+       
+       def set_attribute_value(self, attribute, value, value_class=None):
+               if value_class is None:
+                       from philo.models.base import ManyToManyValue
+                       value_class = ManyToManyValue
+               super(ManyToManyAttribute, self).set_attribute_value(attribute, value, value_class)
 
 
 class TemplateField(models.TextField):