#5868: Newforms ErrorDict serialization problem
-------------------------------------------+--------------------------------
Reporter: tangerine | Owner: nobody
Status: new | Component:
django.newforms
Version: SVN | Resolution:
Keywords: serialization newforms JSON | Stage: Design
decision needed
Has_patch: 0 | Needs_docs: 0
Needs_tests: 0 | Needs_better_patch: 0
-------------------------------------------+--------------------------------
Changes (by gwilson):
* needs_better_patch: => 0
* stage: Unreviewed => Design decision needed
* needs_tests: => 0
* needs_docs: => 0
Comment:
Yes, r6625 turned all newforms error messages into lazy strings, which
aren't supported by the default `JSONEncoder`:
{{{
#!python
>>> from django.utils import simplejson
>>> simplejson.dumps(ugettext_lazy('hello world'))
Traceback (most recent call last):
File "<console>", line 1, in ?
File
"/home/gdub/bzr/django/upstream/django/utils/simplejson/__init__.py", line
181, in dumps
separators=separators,
File
"/home/gdub/bzr/django/upstream/django/utils/simplejson/encoder.py", line
312, in encode
chunks = list(self.iterencode(o))
File
"/home/gdub/bzr/django/upstream/django/utils/simplejson/encoder.py", line
273, in _iterencode
for chunk in self._iterencode_default(o, markers):
File
"/home/gdub/bzr/django/upstream/django/utils/simplejson/encoder.py", line
279, in _iterencode_default
newobj = self.default(o)
File
"/home/gdub/bzr/django/upstream/django/utils/simplejson/encoder.py", line
300, in default
raise TypeError("%r is not JSON serializable" % (o,))
TypeError: <django.utils.functional.__proxy__ object at 0x892378c> is not
JSON serializable
}}}
The `JSONEncoder` docstring states:
{{{
To extend this to recognize other objects, subclass and implement a
``.default()`` method with another method that returns a serializable
object for ``o`` if possible, otherwise it should call the superclass
implementation (to raise ``TypeError``).
}}}
Looks like we might want to do this since lazy strings are used in several
places throughout Django. Here's a quick and dirty one that works:
{{{
#!python
from django.utils.functional import Promise
from django.utils.translation import force_unicode
from django.utils.simplejson import JSONEncoder
class LazyEncoder(JSONEncoder):
def default(self, o):
if isinstance(o, Promise):
return force_unicode(o)
else:
return super(LazyEncoder, self).default(o)
}}}
{{{
#!python
>>> simplejson.dumps(ugettext_lazy('hello world'), cls=LazyEncoder)
'"hello world"'
>>> simplejson.dumps([1, 2, ugettext_lazy('hi')], cls=LazyEncoder)
'[1, 2, "hi"]'
}}}
--
Ticket URL: <http://code.djangoproject.com/ticket/5868#comment:1>
Django Code <http://code.djangoproject.com/>
The web framework for perfectionists with deadlines
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Django updates" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/django-updates?hl=en
-~----------~----~----~----~------~----~------~--~---
