add better error handling for resolving participants and volunteers + tests

Author: YashK2005

backend/app/routes/match.py

@@ -203,32 +203,45 @@ async def request_new_volunteers(
 async def _resolve_acting_participant_id(request: Request, user_service: UserService) -> Optional[UUID]:
     auth_id = getattr(request.state, "user_id", None)
     if not auth_id:
-        return None
+        raise HTTPException(status_code=401, detail="Authentication required")
 
     try:
         role_name = user_service.get_user_role_by_auth_id(auth_id)
-    except ValueError:
-        return None
-
-    if role_name != UserRole.PARTICIPANT.value:
+    except ValueError as exc:
+        raise HTTPException(status_code=401, detail="User not found") from exc
+
+    if role_name == UserRole.PARTICIPANT.value:
+        try:
+            participant_id_str = await user_service.get_user_id_by_auth_id(auth_id)
+        except ValueError as exc:
+            raise HTTPException(status_code=404, detail="Participant not found") from exc
+        return UUID(participant_id_str)
+
+    if role_name == UserRole.ADMIN.value:
+        # Admin callers bypass ownership checks
         return None
 
-    participant_id_str = await user_service.get_user_id_by_auth_id(auth_id)
-    return UUID(participant_id_str)
+    raise HTTPException(status_code=403, detail="Insufficient role for participant operation")
 
 
 async def _resolve_acting_volunteer_id(request: Request, user_service: UserService) -> Optional[UUID]:
     auth_id = getattr(request.state, "user_id", None)
     if not auth_id:
-        return None
+        raise HTTPException(status_code=401, detail="Authentication required")
 
     try:
         role_name = user_service.get_user_role_by_auth_id(auth_id)
-    except ValueError:
-        return None
+    except ValueError as exc:
+        raise HTTPException(status_code=401, detail="User not found") from exc
+
+    if role_name == UserRole.VOLUNTEER.value:
+        try:
+            volunteer_id_str = await user_service.get_user_id_by_auth_id(auth_id)
+        except ValueError as exc:
+            raise HTTPException(status_code=404, detail="Volunteer not found") from exc
+        return UUID(volunteer_id_str)
 
-    if role_name != UserRole.VOLUNTEER.value:
+    if role_name == UserRole.ADMIN.value:
         return None
 
-    volunteer_id_str = await user_service.get_user_id_by_auth_id(auth_id)
-    return UUID(volunteer_id_str)
+    raise HTTPException(status_code=403, detail="Insufficient role for volunteer operation")

backend/tests/unit/test_match_route_helpers.py

@@ -0,0 +1,136 @@
+import pytest
+from fastapi import HTTPException
+from starlette.requests import Request
+
+from app.routes.match import _resolve_acting_participant_id, _resolve_acting_volunteer_id
+from app.schemas.user import UserRole
+
+
+class DummyUserService:
+    def __init__(self, role_map, id_map):
+        self.role_map = role_map
+        self.id_map = id_map
+
+    def get_user_role_by_auth_id(self, auth_id: str) -> str:
+        if auth_id not in self.role_map:
+            raise ValueError("User not found")
+        return self.role_map[auth_id]
+
+    async def get_user_id_by_auth_id(self, auth_id: str) -> str:
+        if auth_id not in self.id_map:
+            raise ValueError("ID not found")
+        return self.id_map[auth_id]
+
+
+@pytest.mark.asyncio
+async def test_resolve_participant_success():
+    request = Request({"type": "http"})
+    request.state.user_id = "auth_participant"
+
+    service = DummyUserService(
+        role_map={"auth_participant": UserRole.PARTICIPANT.value},
+        id_map={"auth_participant": "11111111-1111-1111-1111-111111111111"},
+    )
+
+    participant_id = await _resolve_acting_participant_id(request, service)
+    assert str(participant_id) == "11111111-1111-1111-1111-111111111111"
+
+
+@pytest.mark.asyncio
+async def test_resolve_participant_admin_bypass():
+    request = Request({"type": "http"})
+    request.state.user_id = "auth_admin"
+
+    service = DummyUserService(
+        role_map={"auth_admin": UserRole.ADMIN.value},
+        id_map={},
+    )
+
+    participant_id = await _resolve_acting_participant_id(request, service)
+    assert participant_id is None
+
+
+@pytest.mark.asyncio
+async def test_resolve_participant_missing_user_raises():
+    request = Request({"type": "http"})
+    request.state.user_id = "auth_unknown"
+
+    service = DummyUserService(role_map={}, id_map={})
+
+    with pytest.raises(HTTPException) as exc:
+        await _resolve_acting_participant_id(request, service)
+
+    assert exc.value.status_code == 401
+
+
+@pytest.mark.asyncio
+async def test_resolve_participant_wrong_role_raises():
+    request = Request({"type": "http"})
+    request.state.user_id = "auth_volunteer"
+
+    service = DummyUserService(
+        role_map={"auth_volunteer": UserRole.VOLUNTEER.value},
+        id_map={},
+    )
+
+    with pytest.raises(HTTPException) as exc:
+        await _resolve_acting_participant_id(request, service)
+
+    assert exc.value.status_code == 403
+
+
+@pytest.mark.asyncio
+async def test_resolve_volunteer_success():
+    request = Request({"type": "http"})
+    request.state.user_id = "auth_volunteer"
+
+    service = DummyUserService(
+        role_map={"auth_volunteer": UserRole.VOLUNTEER.value},
+        id_map={"auth_volunteer": "22222222-2222-2222-2222-222222222222"},
+    )
+
+    volunteer_id = await _resolve_acting_volunteer_id(request, service)
+    assert str(volunteer_id) == "22222222-2222-2222-2222-222222222222"
+
+
+@pytest.mark.asyncio
+async def test_resolve_volunteer_missing_user_raises():
+    request = Request({"type": "http"})
+    request.state.user_id = "auth_missing"
+
+    service = DummyUserService(role_map={}, id_map={})
+
+    with pytest.raises(HTTPException) as exc:
+        await _resolve_acting_volunteer_id(request, service)
+
+    assert exc.value.status_code == 401
+
+
+@pytest.mark.asyncio
+async def test_resolve_volunteer_wrong_role_raises():
+    request = Request({"type": "http"})
+    request.state.user_id = "auth_participant"
+
+    service = DummyUserService(
+        role_map={"auth_participant": UserRole.PARTICIPANT.value},
+        id_map={},
+    )
+
+    with pytest.raises(HTTPException) as exc:
+        await _resolve_acting_volunteer_id(request, service)
+
+    assert exc.value.status_code == 403
+
+
+@pytest.mark.asyncio
+async def test_resolve_volunteer_admin_bypass():
+    request = Request({"type": "http"})
+    request.state.user_id = "auth_admin"
+
+    service = DummyUserService(
+        role_map={"auth_admin": UserRole.ADMIN.value},
+        id_map={},
+    )
+
+    volunteer_id = await _resolve_acting_volunteer_id(request, service)
+    assert volunteer_id is None