Misc cleanup

netbox/extras/validators.py

@@ -84,7 +84,7 @@ class CustomValidator:
         # Attempt to resolve many-to-many fields to their stored values
         m2m_fields = [f.name for f in instance._meta.local_many_to_many]
         if name in m2m_fields:
-            if name in instance._m2m_values:
+            if name in getattr(instance, '_m2m_values', []):
                 return instance._m2m_values[name]
             if instance.pk:
                 return list(getattr(instance, name).all())

netbox/netbox/api/serializers/base.py

@@ -23,9 +23,9 @@ class ValidatedModelSerializer(BaseModelSerializer):
     validation. (DRF does not do this by default; see https://github.com/encode/django-rest-framework/issues/3144)
     """
     def validate(self, data):
-
-        # Remove custom fields data (if any) prior to model validation
         attrs = data.copy()
+
+        # Remove custom field data (if any) prior to model validation
         attrs.pop('custom_fields', None)
 
         # Skip ManyToManyFields