From 75b78241c8e7da16dd0c22f94c67c403c79c0603 Mon Sep 17 00:00:00 2001
From: Piotr Cybulski <piotr@piotrcybulski.com>
Date: Sun, 5 Feb 2023 22:52:54 +0100
Subject: [PATCH] Fix handling non-pydantic arguments in view function

---
 flask_pydantic/core.py | 12 ++++++++----
 tests/func/test_app.py | 28 ++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/flask_pydantic/core.py b/flask_pydantic/core.py
index 912415a..e5765ac 100644
--- a/flask_pydantic/core.py
+++ b/flask_pydantic/core.py
@@ -2,6 +2,7 @@
 from typing import Any, Callable, Iterable, List, Optional, Tuple, Type, Union
 
 from flask import Response, current_app, jsonify, make_response, request
+from werkzeug.routing import Rule
 from pydantic import BaseModel, ValidationError
 from pydantic.tools import parse_obj_as
 
@@ -68,12 +69,16 @@ def validate_many_models(model: Type[BaseModel], content: Any) -> List[BaseModel
         raise ManyModelValidationError(ve.errors())
 
 
-def validate_path_params(func: Callable, kwargs: dict) -> Tuple[dict, list]:
+def validate_path_params(
+    func: Callable, kwargs: dict, url_rule: Rule
+) -> Tuple[dict, list]:
     errors = []
     validated = {}
     for name, type_ in func.__annotations__.items():
         if name in {"query", "body", "form", "return"}:
             continue
+        if not url_rule or not name in url_rule.arguments:
+            continue
         try:
             value = parse_obj_as(type_, kwargs.get(name))
             validated[name] = value
@@ -167,7 +172,7 @@ def decorate(func: Callable) -> Callable:
         @wraps(func)
         def wrapper(*args, **kwargs):
             q, b, f, err = None, None, None, {}
-            kwargs, path_err = validate_path_params(func, kwargs)
+            kwargs, path_err = validate_path_params(func, kwargs, request.url_rule)
             if path_err:
                 err["path_params"] = path_err
             query_in_kwargs = func.__annotations__.get("query")
@@ -245,8 +250,7 @@ def wrapper(*args, **kwargs):
                         "FLASK_PYDANTIC_VALIDATION_ERROR_STATUS_CODE", 400
                     )
                     return make_response(
-                        jsonify({"validation_error": err}),
-                        status_code
+                        jsonify({"validation_error": err}), status_code
                     )
             res = func(*args, **kwargs)
 
diff --git a/tests/func/test_app.py b/tests/func/test_app.py
index a01edd7..7a720b7 100644
--- a/tests/func/test_app.py
+++ b/tests/func/test_app.py
@@ -85,6 +85,17 @@ def int_path_param(obj_id):
         return IdObj(id=obj_id)
 
 
+@pytest.fixture
+def app_with_non_pydantic_argument(app):
+    class IdObj(BaseModel):
+        id: str
+
+    @app.route("/path_param/<obj_id>/", methods=["GET"])
+    @validate()
+    def int_path_param(obj_id: str, non_pydantic: ValidationError = None):
+        return IdObj(id=obj_id)
+
+
 @pytest.fixture
 def app_with_custom_root_type(app):
     class Person(BaseModel):
@@ -386,6 +397,23 @@ def test_str_param_passes(self, client):
         assert response.json == expected_response
 
 
+@pytest.mark.usefixtures("app_with_non_pydantic_argument")
+class TestFunctionArgument:
+    def test_int_str_param_passes(self, client):
+        id_ = 12
+        expected_response = {"id": str(id_)}
+        response = client.get(f"/path_param/{id_}/")
+
+        assert response.json == expected_response
+
+    def test_str_param_passes(self, client):
+        id_ = "twelve"
+        expected_response = {"id": id_}
+        response = client.get(f"/path_param/{id_}/")
+
+        assert response.json == expected_response
+
+
 @pytest.mark.usefixtures("app_with_optional_body")
 class TestGetJsonParams:
     def test_empty_body_fails(self, client):