# -*- coding: utf-8 -*-
from __future__ import unicode_literals
from django.conf import settings
from django.core import checks
from django.core.exceptions import FieldDoesNotExist
from django.db import models
class CurrentSiteManager(models.Manager):
"Use this to limit objects to those associated with the current site."
use_in_migrations = True
def __init__(self, field_name=None):
super(CurrentSiteManager, self).__init__()
self.__field_name = field_name
def check(self, **kwargs):
errors = super(CurrentSiteManager, self).check(**kwargs)
errors.extend(self._check_field_name())
return errors
def _check_field_name(self):
field_name = self._get_field_name()
try:
field = self.model._meta.get_field(field_name)
except FieldDoesNotExist:
return [
checks.Error(
"CurrentSiteManager could not find a field named '%s'." % field_name,
obj=self,
id='sites.E001',
)
]
if not field.many_to_many and not isinstance(field, (models.ForeignKey)):
return [
checks.Error(
"CurrentSiteManager cannot use '%s.%s' as it is not a foreign key or a many-to-many field." % (
self.model._meta.object_name, field_name
),
obj=self,
id='sites.E002',
)
]
return []
def _get_field_name(self):
""" Return self.__field_name or 'site' or 'sites'. """
if not self.__field_name:
try:
self.model._meta.get_field('site')
except FieldDoesNotExist:
self.__field_name = 'sites'
else:
self.__field_name = 'site'
return self.__field_name
def get_queryset(self):
return super(CurrentSiteManager, self).get_queryset().filter(
**{self._get_field_name() + '__id': settings.SITE_ID})