[Checkins] SVN: zope.schema/trunk/ fix broken Object field validation. Previous version was using a volatile property on object field values which ends in a ForbiddenAttribute error on security proxied objects.

[Roger Ineichen]

Log message for revision 122904:
  fix broken Object field validation. Previous version was using a volatile property on object field values which ends in a  ForbiddenAttribute error on security proxied objects.

Changed:
  U   zope.schema/trunk/CHANGES.txt
  U   zope.schema/trunk/src/zope/schema/_field.py

-=-
Modified: zope.schema/trunk/CHANGES.txt
===================================================================
--- zope.schema/trunk/CHANGES.txt	2011-09-23 08:41:02 UTC (rev 122903)
+++ zope.schema/trunk/CHANGES.txt	2011-09-23 14:00:51 UTC (rev 122904)
@@ -5,7 +5,9 @@
 3.8.1 (unreleased)
 ------------------
 
-- ...
+- fix broken Object field validation. Previous version was using a volatile
+  property on object field values which ends in a ForbiddenAttribute error
+  on security proxied objects. 
 
 3.8.0 (2011-03-18)
 ------------------

Modified: zope.schema/trunk/src/zope/schema/_field.py
===================================================================
--- zope.schema/trunk/src/zope/schema/_field.py	2011-09-23 08:41:02 UTC (rev 122903)
+++ zope.schema/trunk/src/zope/schema/_field.py	2011-09-23 14:00:51 UTC (rev 122904)
@@ -18,6 +18,7 @@
 
 import re
 import decimal
+import threading
 from datetime import datetime, date, timedelta, time
 from zope.event import notify
 
@@ -452,6 +453,8 @@
         super(FrozenSet, self).__init__(unique=True, **kw)
 
 
+VALIDATED_VALUES = threading.local()
+
 def _validate_fields(schema, value, errors=None):
     if errors is None:
         errors = []
@@ -462,13 +465,12 @@
     if schema is Interface:
         return errors
     # if `value` is part of a cyclic graph, we need to break the cycle to avoid
-    # infinite recursion.
-    #
-    # (use volatile attribute to avoid persistency/conflicts)
-    if hasattr(value, '_v_schema_being_validated'):
+    # infinite recursion. Collect validated objects in a thread local dict by
+    # it's python represenation. A previous version was setting a volatile
+    # attribute which didn't work with security proxy
+    if id(value) in VALIDATED_VALUES.__dict__:
         return errors
-    # Mark the value as being validated.
-    value._v_schema_being_validated = True
+    VALIDATED_VALUES.__dict__[id(value)] = True
     # (If we have gotten here, we know that `value` provides an interface
     # other than zope.interface.Interface;
     # iow, we can rely on the fact that it is an instance
@@ -487,7 +489,7 @@
                     # property for the given name is not implemented
                     errors.append(SchemaNotFullyImplemented(error))
     finally:
-        delattr(value, '_v_schema_being_validated')
+        del VALIDATED_VALUES.__dict__[id(value)]
     return errors