bugfix: unknown author

djangoldp_notification/models.py

@@ -193,7 +193,7 @@ def send_notifications(instance, request_type):
 
 
 def send_request(target, object_iri, instance, request_type):
-    author = get_current_user().urlid
+    author = getattr(get_current_user(), 'urlid', 'unknown')
     # local inbox
     if target.startswith(settings.SITE_URL):
         user = Model.resolve_parent(target.replace(settings.SITE_URL, ''))