try: set except NameError: from sets import Set as set # Python 2.3 fallback from django.db import connection from django.contrib.auth.models import User class ModelBackend(object): """ Authenticates against django.contrib.auth.models.User. """ # TODO: Model, login attribute name and password attribute name should be # configurable. def authenticate(self, username=None, password=None): try: user = User.objects.get(username=username) if user.check_password(password): return user except User.DoesNotExist: return None def get_group_permissions(self, user_obj): """ Returns a set of permission strings that this user has through his/her groups. """ if not hasattr(user_obj, '_group_perm_cache'): cursor = connection.cursor() # The SQL below works out to the following, after DB quoting: # cursor.execute(""" # SELECT ct."app_label", p."codename" # FROM "auth_permission" p, "auth_group_permissions" gp, "auth_user_groups" ug, "django_content_type" ct # WHERE p."id" = gp."permission_id" # AND gp."group_id" = ug."group_id" # AND ct."id" = p."content_type_id" # AND ug."user_id" = %s, [self.id]) qn = connection.ops.quote_name sql = """ SELECT ct.%s, p.%s FROM %s p, %s gp, %s ug, %s ct WHERE p.%s = gp.%s AND gp.%s = ug.%s AND ct.%s = p.%s AND ug.%s = %%s""" % ( qn('app_label'), qn('codename'), qn('auth_permission'), qn('auth_group_permissions'), qn('auth_user_groups'), qn('django_content_type'), qn('id'), qn('permission_id'), qn('group_id'), qn('group_id'), qn('id'), qn('content_type_id'), qn('user_id'),) cursor.execute(sql, [user_obj.id]) user_obj._group_perm_cache = set(["%s.%s" % (row[0], row[1]) for row in cursor.fetchall()]) return user_obj._group_perm_cache def get_all_permissions(self, user_obj): if not hasattr(user_obj, '_perm_cache'): user_obj._perm_cache = set([u"%s.%s" % (p.content_type.app_label, p.codename) for p in user_obj.user_permissions.select_related()]) user_obj._perm_cache.update(self.get_group_permissions(user_obj)) return user_obj._perm_cache def has_perm(self, user_obj, perm): return perm in self.get_all_permissions(user_obj) def has_module_perms(self, user_obj, app_label): """ Returns True if user_obj has any permissions in the given app_label. """ for perm in self.get_all_permissions(user_obj): if perm[:perm.index('.')] == app_label: return True return False def get_user(self, user_id): try: return User.objects.get(pk=user_id) except User.DoesNotExist: return None