traversal.walksubmodel(): Child Submodel Elements of `Entity` and `Operation` are skipped

[ChristophRh]

The code of traversal.walk_submodel() is considering only Submodel Elements inside:

• Submodel: collection.submodel_element
• Submodel Element Collection / List: collection.value

but, according to the specification, Entity and Operation may contain Submodel Elements as well:

• Entity: entity.statement
• Operation: operation.input_variable, operation.output_variable, operation.in_output_variable

That leads to missing files in file_store after reading an AASX file with an Entity containing a Submodel Element File.

[s-heppner]

Hi, thanks for letting us know!

Indeed, util.traversal.walk_submodel() only traverses Submodel.submodel_element, SubmodelElementList.value and SubmodelElementCollection.value.
You are further correct, that Entity.statement and Operation.input_variable, Operation.output_variable and Operation.in_output_variable can contain SubmodelElement(s).

The walk_submodel() method is utilized in adapter.aasx.AASXReader._collect_supplementary_files to look for File SubmodelElements and atm misses those contained in Entity or Operation.

From what the method docstring says, I'd say this is a bug in the behavior. I cannot think of an instance, where we would not want to include Entity and Operation in the traversal. I'll take this report to our dev team to discuss if I overlooked any edge cases, which would make us add a different method (or an option in this method) to exclude Entity and Operation in the traversal, but for now, I think this should be simply fixed.

[zrgt]

Fix proposal:

• Process Entity and Operation attributes which may contain SubmodelElements in traversal.walk_submodel()

@thammel could you fix the issue?