Closes #21303: Cache serialized post-change data on object

netbox/extras/events.py

@@ -53,9 +53,9 @@ def serialize_for_event(instance):
 def get_snapshots(instance, event_type):
     snapshots = {
         'prechange': getattr(instance, '_prechange_snapshot', None),
-        'postchange': None,
+        'postchange': getattr(instance, '_postchange_snapshot', None),
     }
-    if event_type != OBJECT_DELETED:
+    if snapshots['postchange'] is None and event_type != OBJECT_DELETED:
         # Use model's serialize_object() method if defined; fall back to serialize_object() utility function
         if hasattr(instance, 'serialize_object'):
             snapshots['postchange'] = instance.serialize_object()

netbox/netbox/models/features.py

@@ -121,7 +121,8 @@ class ChangeLoggingMixin(DeleteMixin, models.Model):
         if hasattr(self, '_prechange_snapshot'):
             objectchange.prechange_data = self._prechange_snapshot
         if action in (ObjectChangeActionChoices.ACTION_CREATE, ObjectChangeActionChoices.ACTION_UPDATE):
-            objectchange.postchange_data = self.serialize_object(exclude=exclude)
+            self._postchange_snapshot = self.serialize_object(exclude=exclude)
+            objectchange.postchange_data = self._postchange_snapshot
 
         return objectchange