fix(bulk-import): lookup custom object via slug

custom objects are indexed via the view's url, which is derived from the
custom object's slug. the existing bulk import form looked up the custom
object by name though, rather than slug. this commit fixes that bad
lookup field. the bulk import and bulk delete forms already do this.

additionally, we add a slug uniqueness constraint on the custom object
type for additional safeguarding

Author: anshulkamath

netbox_custom_objects/models.py

@@ -209,6 +209,13 @@ class Meta:
                     "A Custom Object Type with this name already exists."
                 ),
             ),
+            models.UniqueConstraint(
+                Lower("slug"),
+                name="%(app_label)s_%(class)s_slug",
+                violation_error_message=_(
+                    "A Custom Object Type with this slug already exists."
+                ),
+            ),
         ]
 
     def __str__(self):

netbox_custom_objects/views.py

@@ -733,7 +733,7 @@ def get_queryset(self, request):
             return self.queryset
         custom_object_type = self.kwargs.get("custom_object_type", None)
         self.custom_object_type = CustomObjectType.objects.get(
-            name__iexact=custom_object_type
+            slug=custom_object_type
         )
         model = self.custom_object_type.get_model_with_serializer()
         return model.objects.all()