Publishing collections.

[redakcja.git] / src / alerts / models.py

diff --git a/src/alerts/models.py b/src/alerts/models.py
index 132531f..a262980 100644 (file)
--- a/src/alerts/models.py
+++ b/src/alerts/models.py
@@ -39,4 +39,5 @@ class Alert(models.Model):
 
 @receiver(post_commit)
 def validate_post_commit(sender, **kwargs):
-    Alert.validate_book(sender.tree.book)
+    if hasattr(sender.tree, 'book'):
+        Alert.validate_book(sender.tree.book)