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
26057	Template {% if perms.app_label.permission %} check failing, but {% if 'app_label.permission' in perms %} works	McAnix	nobody	"I'm encountering the issue above for dynamically generated permissions.

I have a Zone model (see below) in a project named ""Core"" that holds some content and dynamically builds row-level-like permissions for each entry using a post_save and post_delete hook to manage it. Please don't judge me on the usage, it was the simplest solution at the time and the Zone model content changes infrequently.

The issue I'm facing is when using the dynamic permissions in a template. I've tested the following in the template:

{{{
{% if 'core.can_view_myzone' in perms %}Check passes{% endif %} <- WORKS
{% perms.core.can_view_myzone %}Check fails{% endif %} <- DOESN'T WORK
}}}

Also in the view:

{{{
print ""CAN VIEW: %s"" % request.user.has_perm('core.can_view_myzone') <- WORKS
}}}

Other permissions that are created via the permissions variable in the Meta class work fine '''BUT''' not if they're in the Zone model. I have checked migrations and the db tables for django_content_type/auth_permission and everything exists there and links correctly.

Middleware as follows:

{{{
MIDDLEWARE_CLASSES = (
    'django.middleware.common.CommonMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
)
}}}

Template Context Processors:

{{{
TEMPLATE_CONTEXT_PROCESSORS = ('django.contrib.auth.context_processors.auth',
'django.core.context_processors.debug',
'django.core.context_processors.i18n',
'django.core.context_processors.media',
'django.core.context_processors.static',
'django.contrib.messages.context_processors.messages',
'djutils.context_processors.settings_loader') # This just exposes selected settings to the templates
}}}

{{{
class Zone(models.Model):
  """"""A holder model for zone information as well as permission slips for each zone""""""
  
  class Meta:
    permissions = ()
  
  cdate = models.DateTimeField(auto_now_add=True)
  name = models.CharField(max_length=63)
  url = models.CharField(max_length=255, verbose_name=""Zone URL"")
  enabled = models.BooleanField()
  
  def __unicode__(self):
    return ""%s (Enabled: %s)"" % (self.name, self.enabled)

def create_zone_permission(sender, instance, created, raw, using, **kwargs):
  """"""Creates a new zone permission entry for the new zone""""""
  content_type = ContentType.objects.get(app_label='core', model='zone')
  codename = 'can_view_%s' % (instance.name, )
  name='Can View %s' % (instance.name, )
  
  if not Permission.objects.using(using).filter(codename=codename, content_type=content_type).exists():
    logger.info(""Creating zone specific permissions for %s"" % (codename, ))
    Permission.objects.using(using).create(codename=codename, name=name, content_type=content_type)


def delete_zone_permission(sender, instance, using, **kwargs):
  """"""Creates a new zone permission entry for the new zone""""""
  content_type = ContentType.objects.get(app_label='core', model='zone')
  codename = 'can_view_%s' % (instance.name, )
  
  if Permission.objects.using(using).filter(codename=codename, content_type=content_type).exists():
    logger.info(""Deleting zone specific permissions for %s"" % (codename, ))
    permission = Permission.objects.using(using).filter(codename=codename, content_type=content_type)
    
    permission.delete(using=using)
    
post_save.connect(create_zone_permission, sender=Zone)
post_delete.connect(delete_zone_permission, sender=Zone)
}}}"	Bug	new	Template system	1.8	Normal		permissions		Unreviewed	0	0	0	0	0	0