Properly handle the post delete signal in transactions

If the model changes are committed in a transaction,
at the time when the post delete signal is handled
instance.pk returns None.

Store the instance's ID beforehand so that it is available
when creating the CRUDEvent.

easyaudit/signals/crud_flows.py

@@ -35,15 +35,15 @@ def get_current_user_details():
     return user_id, user_pk_as_string
 
 
-def log_event(event_type, instance, object_json_repr, **kwargs):
+def log_event(event_type, instance, object_id, object_json_repr, **kwargs):
     user_id, user_pk_as_string = get_current_user_details()
     with transaction.atomic(using=DATABASE_ALIAS):
         audit_logger.crud(
             {
                 "content_type_id": ContentType.objects.get_for_model(instance).id,
                 "datetime": timezone.now(),
                 "event_type": event_type,
-                "object_id": instance.pk,
+                "object_id": object_id,
                 "object_json_repr": object_json_repr or "",
                 "object_repr": str(instance),
                 "user_id": user_id,
@@ -70,6 +70,7 @@ def pre_save_crud_flow(instance, object_json_repr, changed_fields):
         log_event(
             CRUDEvent.UPDATE,
             instance,
+            instance.pk,
             object_json_repr,
             changed_fields=changed_fields,
         )
@@ -82,6 +83,7 @@ def post_save_crud_flow(instance, object_json_repr):
         log_event(
             CRUDEvent.CREATE,
             instance,
+            instance.pk,
             object_json_repr,
         )
     except Exception:
@@ -102,18 +104,20 @@ def m2m_changed_crud_flow(  # noqa: PLR0913
         log_event(
             event_type,
             instance,
+            instance.pk,
             object_json_repr,
             changed_fields=changed_fields,
         )
     except Exception:
         handle_flow_exception(instance, "m2m_changed")
 
 
-def post_delete_crud_flow(instance, object_json_repr):
+def post_delete_crud_flow(instance, object_id, object_json_repr):
     try:
         log_event(
             CRUDEvent.DELETE,
             instance,
+            object_id,
             object_json_repr,
         )
 

easyaudit/signals/model_signals.py

@@ -241,10 +241,13 @@ def post_delete(sender, instance, using, **kwargs):
 
         with transaction.atomic(using=using):
             object_json_repr = serializers.serialize("json", [instance])
+            # instance.pk returns None if the changes are performed within a transaction
+            object_id = instance.pk
 
             crud_flow = partial(
                 post_delete_crud_flow,
                 instance=instance,
+                object_id=object_id,
                 object_json_repr=object_json_repr,
             )
             if getattr(settings, "TEST", False):

tests/test_main.py

@@ -4,6 +4,7 @@
 from asgiref.sync import sync_to_async
 from django.contrib.contenttypes.models import ContentType
 from django.core import management
+from django.db import transaction
 from django.urls import reverse
 from django.utils.version import get_version
 from pytest_django.asserts import assertInHTML
@@ -189,6 +190,28 @@ def test_delete(self, model):
         )
         assert crud_event_qs.count() == 2
 
+    @pytest.mark.django_db(transaction=True)
+    def test_delete_transaction(self, model, settings):
+        settings.TEST = False
+
+        with transaction.atomic():
+            obj = model.objects.create()
+            model.objects.all().delete()
+
+        crud_event_qs = CRUDEvent.objects.filter(
+            object_id=obj.id,
+            content_type=ContentType.objects.get_for_model(obj),
+            event_type=CRUDEvent.CREATE,
+        )
+        assert crud_event_qs.count() == 1
+
+        crud_event_qs = CRUDEvent.objects.filter(
+            object_id=obj.id,
+            content_type=ContentType.objects.get_for_model(obj),
+            event_type=CRUDEvent.DELETE,
+        )
+        assert crud_event_qs.count() == 1
+
     @pytest.mark.usefixtures("_audit_logger")
     def test_propagate_exceptions(self, model, settings):
         with pytest.raises(ValueError, match="Test exception"):