Add functions to look up a LinkML python class by URI or CURIE

Author: hsolbrig

linkml_runtime/utils/yamlutils.py

@@ -6,7 +6,7 @@
 from deprecated.classic import deprecated
 from jsonasobj2 import JsonObj, as_json, as_dict, JsonObjTypes, items
 import jsonasobj2
-from rdflib import Graph
+from rdflib import Graph, URIRef
 from yaml.constructor import ConstructorError
 
 from linkml_runtime.utils.context_utils import CONTEXTS_PARAM_TYPE, merge_contexts
@@ -243,6 +243,26 @@ def _normalize_inlined_slot(self, slot_name: str, slot_type: Type, key_name: Opt
                     self[slot_name] = dict_slot[0]
             self._normalize_inlined_as_dict(slot_name, slot_type, key_name, keyed)
 
+    @classmethod
+    def _class_for(cls, attribute: str, uri_or_curie: Union[str, URIRef]) -> Optional[Type["YAMLRoot"]]:
+        """ Locate self or descendant class that has attribute == uri_or_curie """
+        if getattr(cls, attribute, None) == uri_or_curie:
+            return cls
+        for subclass in cls.__subclasses__():
+            match = subclass._class_for(attribute, uri_or_curie)
+            if match:
+                return match
+        return None
+
+    def _class_for_uri(self, uri: str, use_model_uri: bool = False) -> Optional["YAMLRoot"]:
+        """
+        Return the self or descendant of self having with a matching class uri
+        """
+        return self.__class__._class_for('class_model_uri' if use_model_uri else 'class_class_uri', URIRef(uri))
+
+    def _class_for_curie(self, curie: str) -> Optional["YAMLRoot"]:
+        return self.__class__._class_for('class_class_curie', curie)
+
     # ==================
     # Error intercepts
     # ==================

tests/test_utils/test_poly_dataclasses.py

@@ -0,0 +1,31 @@
+import unittest
+from linkml_runtime.linkml_model.meta import Element, LINKML
+
+class PolyDataclassTestCase(unittest.TestCase):
+    def test_class_for_uri(self):
+        """ Test various class lookup options """
+        e = Element(name="Test")
+
+        # Test class URI
+        cls = e._class_for_uri(LINKML.ClassDefinition)
+        self.assertEqual('ClassDefinition', cls.__name__)
+
+        # Test model URI
+        cls = e._class_for_uri(LINKML.TypeDefinition, use_model_uri=True)
+        self.assertEqual('TypeDefinition', cls.__name__)
+
+        # Test class curie (note there isn't any model curie
+        cls = e._class_for_curie("linkml:TypeDefinition")
+        self.assertEqual('TypeDefinition', cls.__name__)
+
+        # Make sure the self test works
+        cls = e._class_for_uri(LINKML.Element)
+        self.assertEqual('Element', cls.__name__)
+
+        # Make sure we fail gracefully
+        cls = e._class_for_uri("linkml:Missing")
+        self.assertIsNone(cls)
+
+
+if __name__ == '__main__':
+    unittest.main()