One-to-many relations

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mrstone

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Jul 5, 2007, 4:19:04 AM7/5/07

to Django users

Hi all

I have a problem I have been struggeling with for a while.

I have two models:

InfoProxy and Permission

A InfoProxy can have several Permissions

class Permission(models.Model):
info_proxy = models.ForeignKey(InfoProxy,
related_name='permissions')
permission_type = models.CharField(maxlength=1,
choices=PERMISSION_CHOICES)
usergroup = models.ForeignKey(UserGroup)

class InfoProxy(models.Model, UrlItem):
"""
A proxy pointing to a (Info)Item
"""
info_type = models.ForeignKey(ContentType,
related_name='infoproxies')
info_id = models.PositiveIntegerField()
info_item = generic.GenericForeignKey(ct_field="info_type",
fk_field="info_id")

render_type = models.ForeignKey(ContentType,
related_name='render_infoproxies', blank=True, null=True)
render_id = models.PositiveIntegerField(blank=True, null=True)
render_item = generic.GenericForeignKey(ct_field="render_type",
fk_field="render_id")

created = models.DateTimeField('date created')
modified = models.DateTimeField('date modified')
owner = models.ForeignKey(User)

language_code = models.CharField(maxlength=20)
rank = models.IntegerField( blank=True, null=True)
grade = models.IntegerField( blank=True, null=True)
objects = InfoProxyManager()

I want to query for all object a user has permission to read depending
on groups (code below)
This code works without any problems on developer server. On
mod_python however I (sometimes) get the below error.
If I hit refresh in the browser, it usually works.

I have tried several things like:
All imports are with full paths
Classes put in site-packages
(Maybe something is wrong when loading classes)
I have checked so at least one permission exist on every InfoProxy

Anyone have had a similar problem?
Any hint that can help me try other options?

Any help is very much appreciated.
Sten

------------------------------------------
Error trace
------------------------------------------
File "/usr/local/lib/python2.4/site-packages/django/core/handlers/
base.py", line 77, in get_response
response = callback(request, *callback_args, **callback_kwargs)

File "/usr/local/lib/python2.4/site-packages/jellyspot/server/apps/
locations/proxy/views.py", line 264, in flashes
result_list = ResultList(request, query)

File "/usr/local/lib/python2.4/site-packages/jellyspot/server/apps/
common/results.py", line 36, in __init__
self.get_results(request)

File "/usr/local/lib/python2.4/site-packages/jellyspot/server/apps/
common/results.py", line 84, in get_results
raise IncorrectLookupParameters(str(e))

IncorrectLookupParameters: Cannot resolve keyword 'permissions' into
field. Choices are: id, info_type, info_id, render_type, render_id,
created, modified, owner, indexer, language_code, rank, grade

--------------------------------------------------------------------------------
query code
--------------------------------------------------------------------------------
try:
if user and user.is_authenticated():

query = """select uub.usergroup_id from users_buddy
as ub
left join users_usergroup_buddies as uub on
uub.buddy_id = ub.id where ub.buddy_id = %s
""" % (user.id)

cursor = connection.cursor()
cursor.execute(query)

group_idents = [item[0] for item in cursor.fetchall()]
group_idents.append(USERGROUP_MEMBERS.id)
else:
group_idents = []

group_idents.append(USERGROUP_EVERYONE.id)

if user and user.is_authenticated():
qs = self.all().filter( Q(owner__exact=user.id) |

Q(permissions__usergroup__in=group_idents)).distinct()
else:
qs =
self.all().filter(permissions__usergroup__in=group_idents).distinct()