id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
9952	to_python being called with unicode text breaks Unpickler	Mark Jones	nobody	"I have a database column that contains a pickle.  When the model tries to access it as a custom field, I run into this problem:

{{{
>>> QuizQuestion.objects.get(pk=1)
class= <type 'unicode'>
(I1
I2
I3
I4
tp0
.

Traceback (most recent call last):
  File ""<console>"", line 1, in <module>
  File ""c:\Python25\Lib\site-packages\django\db\models\manager.py"", line 93, in get
    return self.get_query_set().get(*args, **kwargs)
  File ""c:\Python25\Lib\site-packages\django\db\models\query.py"", line 304, in get
    num = len(clone)
  File ""c:\Python25\Lib\site-packages\django\db\models\query.py"", line 160, in __len__
    self._result_cache = list(self.iterator())
  File ""c:\Python25\Lib\site-packages\django\db\models\query.py"", line 280, in iterator
    obj = self.model(*row[index_start:])
  File ""c:\Python25\Lib\site-packages\django\db\models\base.py"", line 213, in __init__
    setattr(self, field.attname, val)
  File ""c:\Python25\Lib\site-packages\django\db\models\fields\subclassing.py"", line 32, in __set__
    obj.__dict__[self.field.name] = self.field.to_python(value)
  File ""P:\home\mark\Python\intomec\..\intomec\tenq\models.py"", line 42, in to_python
    return pickle.loads(value)
  File ""c:\Python25\lib\pickle.py"", line 1374, in loads
    return Unpickler(file).load()
  File ""c:\Python25\lib\pickle.py"", line 858, in load
    dispatch[key](self)
KeyError: '\x00'
>>>
}}}



the class= part (right before the Traceback) is printed by the class right before the problem in pickle.loadds

Why is the db output converted into unicode before to_python is called?  the !KeyError is because the Unpickler expects a bytestream, not a unicode stream....."		closed	Database layer (models, ORM)	1.0		wontfix	CustomFields		Unreviewed	0	0	0	0	0	0