allows mask for Oauth2

apps/permission/backends.py

@@ -39,7 +39,15 @@ class PermissionBackend(ModelBackend):
 
             def permission_filter(membership_obj):
                 query = Q(pk=-1)
+                if 'mask' in request.GET:
+                    try:
+                        rank = int(request.GET['mask'])
+                    except:
+                        rank = 42
+                    query &= Q(mask__rank__lte=rank)
                 for scope in request.auth.scope.split(' '):
+                    if scope == "openid":
+                        continue
                     permission_id, club_id = scope.split('_')
                     if int(club_id) == membership_obj.club_id:
                         query |= Q(pk=permission_id)