Bonsai Classification Implementation

Version: Bonsai v0.8.x | IfcOpenShell v0.8.x | Python 3.11+ Module paths: bonsai.bim.module.classification, bonsai.bim.module.bsdd IFC schemas: IFC2X3, IFC4, IFC4X3

Critical Warnings

• ALWAYS use ifcopenshell.api.run("classification.add_reference", ...) with products (list), NOT product (singular). The API requires a list even for single elements.
• NEVER use identifier URIs (identifier.buildingsmart.org) for bSDD API calls. ALWAYS use api.bsdd.buildingsmart.org endpoints.
• ALWAYS filter bSDD searches by related_ifc_entity to prevent incorrect classification assignments.
• NEVER hardcode classification codes without verifying them against the source (bSDD or library file).
• In IFC2X3, the attribute is ItemReference, NOT Identification. The IfcOpenShell API handles this migration automatically when using add_reference.

Decision Tree: Classification Source Selection