Logout throws Validation Error when using next branch

[gertzakis]

Environment

• Nautobot version (Docker tag too if applicable): v2.2.0a1
• Python version: 3.8
• Database platform, version: Postgres
• Middleware(s):

This is applicable when using the next branch with version v2.2.0a1.

Steps to Reproduce

1. Login with a User
2. Logout

Expected Behavior

Logout successfully

Observed Behavior

A ValidationError is thrown at /logout/ with message ['“4ci8je1rmskkfei3g8avd9mt2da2bft5” is not a valid UUID.'] when I use the next branch.

[glennmatthews]

Thanks for filing the issue! We actually just noticed this bug yesterday on the core team. :-)

The issue is in the _handle_deleted_object signal, which is being triggered when the user logs out and their session DB record gets deleted. This signal is missing logic to handle the case where the deleted object has a PK that isn't of type UUID. A first pass fix is something like:

diff --git a/nautobot/extras/signals.py b/nautobot/extras/signals.py
index 86ad2aca8..17a31217c 100644
--- a/nautobot/extras/signals.py
+++ b/nautobot/extras/signals.py
@@ -20,6 +20,7 @@ from django_prometheus.models import model_deletes, model_inserts, model_updates
 
 from nautobot.core.celery import app, import_jobs_as_celery_tasks
 from nautobot.core.utils.config import get_settings_or_config
+from nautobot.core.utils.data import is_uuid
 from nautobot.extras.choices import JobResultStatusChoices, ObjectChangeActionChoices
 from nautobot.extras.constants import CHANGELOG_MAX_CHANGE_CONTEXT_DETAIL
 from nautobot.extras.models import (
@@ -165,6 +166,10 @@ def _handle_deleted_object(sender, instance, **kwargs):
     if change_context_state.get() is None:
         return
 
+    if not is_uuid(instance.pk):
+        # Probably some system object
+        return
+
     associations = ContactAssociation.objects.filter(
         associated_object_type=ContentType.objects.get_for_model(type(instance)), associated_object_id=instance.pk
     )

but we're having some discussions about whether there may be a more elegant way to fix it.

[glennmatthews]

Fixed by #5322.