Initial raw_id_fields support for proxy fields. Involves hacks to bypass model valida...

[philo.git] / contrib / cowell / fields.py

diff --git a/contrib/cowell/fields.py b/contrib/cowell/fields.py
index d9f3c8a..c5db56d 100644 (file)
--- a/contrib/cowell/fields.py
+++ b/contrib/cowell/fields.py
@@ -1,6 +1,6 @@
 """
-The Attributes defined in this file can be assigned as fields on a proxy of
-a subclass of philo.models.Entity. They act like any other model fields,
+The Attributes defined in this file can be assigned as fields on a
+subclass of philo.models.Entity. They act like any other model fields,
 but instead of saving their data to the database, they save it to
 attributes related to a model instance. Additionally, a new attribute will
 be created for an instance if and only if the field's value has been set.
@@ -14,10 +14,8 @@ Example::
        
        class ThingProxy(Thing):
                improvised = JSONAttribute(models.BooleanField)
-               
-               class Meta:
-                       proxy = True
 """
+from itertools import tee
 from django import forms
 from django.core.exceptions import FieldError
 from django.db import models
@@ -34,11 +32,12 @@ ATTRIBUTE_REGISTRY = '_attribute_registry'
 
 
 class EntityProxyField(object):
-       def __init__(self, verbose_name=None, help_text=None, default=NOT_PROVIDED, editable=True, *args, **kwargs):
+       def __init__(self, verbose_name=None, help_text=None, default=NOT_PROVIDED, editable=True, choices=None, *args, **kwargs):
                self.verbose_name = verbose_name
                self.help_text = help_text
                self.default = default
                self.editable = editable
+               self._choices = choices or []
        
        def actually_contribute_to_class(self, sender, **kwargs):
                sender._entity_meta.add_proxy_field(self)
@@ -71,6 +70,14 @@ class EntityProxyField(object):
        
        def has_default(self):
                return self.default is not NOT_PROVIDED
+       
+       def _get_choices(self):
+               if hasattr(self._choices, 'next'):
+                       choices, self._choices = tee(self._choices)
+                       return choices
+               else:
+                       return self._choices
+       choices = property(_get_choices)
 
 
 class AttributeFieldDescriptor(object):
@@ -215,6 +222,15 @@ class ForeignKeyAttribute(AttributeField):
        def value_from_object(self, obj):
                relobj = super(ForeignKeyAttribute, self).value_from_object(obj)
                return getattr(relobj, 'pk', None)
+       
+       @property
+       def to(self):
+               """Spoof being a rel from a ForeignKey."""
+               return self.model
+       
+       def get_related_field(self):
+               """Again, spoof being a rel from a ForeignKey."""
+               return self.model._meta.pk
 
 
 class ManyToManyAttribute(ForeignKeyAttribute):