Enh/attributes in schema validation (#822)

* add checking of data properties (attributes) in schema validation

* Use FOAF from web archive

osp/core/utils/schema_validation.py

@@ -5,6 +5,7 @@
 import yaml
 
 from osp.core.namespaces import get_entity
+from osp.core.ontology import OntologyAttribute, OntologyRelationship
 
 logger = logging.getLogger(__name__)
 
@@ -97,9 +98,22 @@ def _load_data_model_from_yaml(data_model_file):
 
 def _check_cuds_object_cardinality(origin_cuds, dest_oclass, rel, constraints):
 
-    actual_cardinality = len(
-        origin_cuds.get(rel=get_entity(rel), oclass=get_entity(dest_oclass))
-    )
+    rel_entity = get_entity(rel)
+
+    if type(rel_entity) == OntologyRelationship:
+        actual_cardinality = len(
+            origin_cuds.get(rel=rel_entity, oclass=get_entity(dest_oclass))
+        )
+    elif type(rel_entity) == OntologyAttribute:
+        # No datatype checking since this is already done when Cuds are
+        # instantiated or imported from a file
+        actual_cardinality = (
+            1 if rel_entity in origin_cuds.get_attributes() else 0
+        )
+    else:
+        raise ConsistencyError(
+            f"Relation '{rel}' not supported for {origin_cuds.oclass}."
+        )
 
     min, max = _interpret_cardinality_value_from_constraints(constraints)
     if actual_cardinality < min or actual_cardinality > max:

tests/test_utils.py

@@ -134,6 +134,11 @@ def test_validate_tree_against_schema(self):
             "test_validation_schema_city_with_optional_subtree.yml",
         )
 
+        schema_file_with_attribute = os.path.join(
+            os.path.dirname(__file__),
+            "test_validation_schema_city_with_attribute.yml",
+        )
+
         c = city.City(name="freiburg")
 
         # empty city is not valid
@@ -188,6 +193,8 @@ def test_validate_tree_against_schema(self):
             schema_file_with_missing_entity,
         )
 
+        validate_tree_against_schema(c, schema_file_with_attribute)
+
     def test_branch(self):
         """Test the branch function."""
         x = branch(

tests/test_validation_schema_city_with_attribute.yml

@@ -0,0 +1,33 @@
+version: "1.0.0"
+
+oclass: city.City
+
+model:
+    city.City:
+        city.name:
+            STRING:
+                cardinality: 1
+        city.hasInhabitant:
+            city.Citizen:
+                cardinality: 1-2
+        city.hasPart:
+            city.Neighborhood:
+                cardinality: 1
+
+    city.Neighborhood:
+        city.name:
+            STRING:
+                cardinality: 1
+        city.hasPart:
+            city.Street:
+                cardinality: 1+
+
+    city.Street:
+        city.name:
+            STRING:
+                cardinality: 1
+
+    city.Citizen:
+        city.name:
+            STRING:
+                cardinality: 1