Fix path parameter validation to work with dependency injection

flask_pydantic/core.py

@@ -86,8 +86,12 @@ def validate_many_models(
 def validate_path_params(func: Callable, kwargs: dict) -> Tuple[dict, list]:
     errors = []
     validated = {}
+    # Only validate parameters that are actual path parameters from the route
+    # request.view_args contains only the path parameters extracted from the URL
+    path_param_names = set(request.view_args.keys()) if request.view_args else set()
+
     for name, type_ in func.__annotations__.items():
-        if name in {"query", "body", "form", "return"}:
+        if name not in path_param_names:
             continue
         try:
             if not isinstance(type_, V1BaseModel):

tests/func/test_app.py

@@ -1,6 +1,7 @@
 import asyncio
 import re
-from typing import List, Optional
+from functools import wraps
+from typing import Any, Callable, List, Optional
 
 import pytest
 from flask import jsonify, request
@@ -89,6 +90,27 @@ def int_path_param(obj_id):
         return IdObj(id=obj_id)
 
 
+@pytest.fixture
+def app_with_path_param_route_and_injector(app):
+    class Injectable:
+        def __init__(self, foo: str):
+            self.foo = foo
+
+    def inject(fun: Callable) -> Callable:
+        @wraps(fun)
+        def wrapper(*args: Any, **kwargs: Any) -> Any:
+            kwargs["injectable"] = Injectable("injected")
+            return fun(*args, **kwargs)
+
+        return wrapper
+
+    @app.route("/path_param/<obj_id>/", methods=["GET"])
+    @inject
+    @validate()
+    def int_path_param(obj_id: int, injectable: Injectable):
+        return {"id": obj_id, "injectable": injectable.foo}
+
+
 @pytest.fixture
 def app_with_custom_root_type(app):
     class Person(BaseModel):
@@ -429,6 +451,36 @@ def test_str_param_passes(self, client):
         assert_matches(expected_response, response.json)
 
 
+@pytest.mark.usefixtures("app_with_path_param_route_and_injector")
+class TestPathIntParameterAndInjector:
+    def test_correct_param_passes(self, client):
+        id_ = 12
+        expected_response = {"id": id_, "injectable": "injected"}
+        response = client.get(f"/path_param/{id_}/")
+        assert_matches(expected_response, response.json)
+
+    def test_string_parameter(self, client):
+        expected_response = {
+            "validation_error": {
+                "path_params": [
+                    {
+                        "input": "not_an_int",
+                        "loc": ["obj_id"],
+                        "msg": "Input should be a valid integer, unable to parse string as an integer",
+                        "type": "int_parsing",
+                        "url": re.compile(
+                            r"https://errors\.pydantic\.dev/.*/v/int_parsing"
+                        ),
+                    }
+                ]
+            }
+        }
+        response = client.get("/path_param/not_an_int/")
+
+        assert_matches(expected_response, response.json)
+        assert response.status_code == 400
+
+
 @pytest.mark.usefixtures("app_with_optional_body")
 class TestGetJsonParams:
     def test_empty_body_fails(self, client):