Guarded the allOf attribute lookup in resources.py using Python's hasattr built-in function:

        if hasattr(resource_template, "allOf") and resource_template.allOf is not None:

Author: James Chapman

api_app/db/repositories/resources.py

@@ -113,7 +113,7 @@ async def validate_input_against_template(self, template_name: str, resource_inp
 
     def _get_all_property_keys_from_template(self, resource_template: ResourceTemplate) -> set:
         properties = set(resource_template.properties.keys())
-        if resource_template.allOf is not None:
+        if hasattr(resource_template, "allOf") and resource_template.allOf is not None:
             for condition in resource_template.allOf:
                 if "then" in condition and "properties" in condition["then"]:
                     properties.update(condition["then"]["properties"].keys())