fix(modeling): resolve in-document JSON Schema $ref paths before Pydantic model creation

src/mcpadapt/utils/modeling.py

@@ -1,7 +1,7 @@
-from copy import deepcopy
 from typing import Any, Dict, ForwardRef, List, Optional, Type, Union
+
+import jsonref
 from pydantic import BaseModel, Field, create_model
-import re
 
 json_type_mapping: dict[str, Type] = {
     "string": str,
@@ -13,31 +13,10 @@
 }
 
 
-def resolve_refs_and_remove_defs(json_obj):
-    # Extract $defs
-    defs = json_obj.get("$defs", {})
-
-    # Function to recursively resolve $ref
-    def _resolve(obj):
-        if isinstance(obj, dict):
-            if "$ref" in obj:
-                ref_path = obj["$ref"]
-                match = re.match(r"#/\$defs/(\w+)", ref_path)
-                if match:
-                    def_key = match.group(1)
-                    return _resolve(deepcopy(defs.get(def_key, {})))
-            return {k: _resolve(v) for k, v in obj.items()}
-        elif isinstance(obj, list):
-            return [_resolve(i) for i in obj]
-        else:
-            return obj
-
-    json_obj = _resolve(json_obj)
-
-    # Remove $defs
-    json_obj.pop("$defs", None)
-
-    return json_obj
+def resolve_refs_and_remove_defs(json_obj: dict[str, Any]) -> dict[str, Any]:
+    """Resolve JSON Schema $ref pointers (including in-document paths) and strip $defs."""
+    resolved = jsonref.replace_refs(json_obj, proxies=False)
+    return {key: value for key, value in resolved.items() if key != "$defs"}
 
 
 def create_model_from_json_schema(

tests/utils/test_modeling.py

@@ -2,7 +2,10 @@
 Tests for the modeling module, specifically focused on JSON Schema handling.
 """
 
-from mcpadapt.utils.modeling import create_model_from_json_schema
+from mcpadapt.utils.modeling import (
+    create_model_from_json_schema,
+    resolve_refs_and_remove_defs,
+)
 
 
 def test_direct_modeling_with_list_type():
@@ -35,3 +38,38 @@ def test_direct_modeling_with_list_type():
     # Verify the model works as expected with number
     instance = model(multi_type_field=42)
     assert instance.multi_type_field == 42
+
+
+def test_create_model_with_property_path_ref():
+    """Regression for #75: in-document $ref paths must be resolved before modeling."""
+    schema = {
+        "type": "object",
+        "properties": {
+            "requestResponse": {
+                "type": "object",
+                "properties": {
+                    "request": {
+                        "type": "object",
+                        "properties": {
+                            "filename": {"type": "string"},
+                            "body": {"type": "string"},
+                        },
+                        "required": ["body"],
+                        "additionalProperties": False,
+                    },
+                    "response": {
+                        "$ref": "#/properties/requestResponse/properties/request"
+                    },
+                },
+                "required": ["request", "response"],
+                "additionalProperties": False,
+            }
+        },
+        "additionalProperties": False,
+    }
+
+    model = create_model_from_json_schema(resolve_refs_and_remove_defs(schema))
+
+    generated_schema = model.model_json_schema()
+    assert "requestResponse" in generated_schema["properties"]
+    assert "$ref" not in str(generated_schema)