from django.db import models
-from django.db.models import signals
-from django.core.exceptions import ObjectDoesNotExist, FieldError
-from django.contrib.contenttypes.models import ContentType
-from functools import partial
-from philo.models.base import Attribute, Relationship, Entity
+from django import forms
+from django.core.exceptions import FieldError
+from philo.models.base import Entity
+from philo.signals import entity_class_prepared
__all__ = ('AttributeField', 'RelationshipField')
+class EntityProxyField(object):
+ descriptor_class = None
+
+ def __init__(self, *args, **kwargs):
+ if self.descriptor_class is None:
+ raise NotImplementedError('EntityProxyField subclasses must specify a descriptor_class.')
+
+ def actually_contribute_to_class(self, sender, **kwargs):
+ sender._entity_meta.add_proxy_field(self)
+ setattr(sender, self.attname, self.descriptor_class(self))
+
+ def contribute_to_class(self, cls, name):
+ if issubclass(cls, Entity):
+ self.name = name
+ self.attname = name
+ entity_class_prepared.connect(self.actually_contribute_to_class, sender=cls)
+ else:
+ raise FieldError('%s instances can only be declared on Entity subclasses.' % self.__class__.__name__)
+
+ def formfield(self, *args, **kwargs):
+ raise NotImplementedError('EntityProxyField subclasses must implement a formfield method.')
+
+ def value_from_object(self, obj):
+ return getattr(obj, self.attname)
+
+
class AttributeFieldDescriptor(object):
def __init__(self, field):
self.field = field
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:
+ return None
try:
- return instance.attribute_set.get(key__exact=self.field.key).value
- except ObjectDoesNotExist:
+ return instance.attributes[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):
- try:
- attribute = instance.attribute_set.get(key__exact=self.field.key)
- except ObjectDoesNotExist:
- attribute = Attribute()
- attribute.entity = instance
- attribute.key = self.field.key
- attribute.value = value
- attribute.save()
+ 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
def __delete__(self, instance):
- instance.attribute_set.filter(key__exact=self.field.key).delete()
+ 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)
-class AttributeField(object):
- def __init__(self, key):
- self.key = key
+class AttributeField(EntityProxyField):
+ descriptor_class = AttributeFieldDescriptor
- def actually_contribute_to_class(self, sender, **kwargs):
- setattr(sender, self.name, AttributeFieldDescriptor(self))
+ def __init__(self, key, field_template=None):
+ self.key = key
+ if field_template is None:
+ field_template = models.CharField(max_length=255)
+ self.field_template = field_template
- def contribute_to_class(self, cls, name):
- if issubclass(cls, Entity):
- self.name = name
- signals.class_prepared.connect(self.actually_contribute_to_class, sender=cls)
- else:
- raise FieldError('AttributeFields can only be declared on Entity subclasses.')
+ def formfield(self, *args, **kwargs):
+ field = self.field_template.formfield(*args, **kwargs)
+ field.required = False
+ return field
class RelationshipFieldDescriptor(object):
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.relationship_set.get(key__exact=self.field.key).value
- except ObjectDoesNotExist:
+ 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))):
- try:
- relationship = instance.relationship_set.get(key__exact=self.field.key)
- except ObjectDoesNotExist:
- relationship = Relationship()
- relationship.entity = instance
- relationship.key = self.field.key
- relationship.value = value
- relationship.save()
+ 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 \'%\' attribute can only be set using existing Model objects.' % self.field.name)
+ raise AttributeError('The \'%s\' attribute can only be set using existing Model objects.' % self.field.name)
def __delete__(self, instance):
- instance.relationship_set.filter(key__exact=self.field.key).delete()
+ 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)
-class RelationshipField(object):
- def __init__(self, key):
+class RelationshipField(EntityProxyField):
+ descriptor_class = RelationshipFieldDescriptor
+
+ def __init__(self, key, model, limit_choices_to=None):
self.key = key
+ self.model = model
+ if limit_choices_to is None:
+ limit_choices_to = {}
+ self.limit_choices_to = limit_choices_to
- def actually_contribute_to_class(self, sender, **kwargs):
- setattr(sender, self.name, RelationshipFieldDescriptor(self))
+ def formfield(self, form_class=forms.ModelChoiceField, **kwargs):
+ field = form_class(self.model._default_manager.complex_filter(self.limit_choices_to), **kwargs)
+ field.required = False
+ return field
- def contribute_to_class(self, cls, name):
- if issubclass(cls, Entity):
- self.name = name
- signals.class_prepared.connect(self.actually_contribute_to_class, sender=cls)
- else:
- raise FieldError('RelationshipFields can only be declared on Entity subclasses.')
\ No newline at end of file
+ def value_from_object(self, obj):
+ relobj = super(RelationshipField, self).value_from_object(obj)
+ return getattr(relobj, 'pk', None)
\ No newline at end of file
git.ithinksw.org / philo.git / blobdiff