OK

cpp/src/heartland.schemas

@@ -159,7 +159,7 @@ namespace heartland_schemas
                             "description": "The transportation methods supported by the network edge (see Transportation Categorization Specification)"
                         }
                     },
-                    "required": ["key", "name", "source", "target"]
+                    "required": ["name", "source", "target"]
                 }
             },
             "required": ["directed", "graph", "nodes", "links"]