Fab auth manager returns get_id of integer type where str is expected

[tirkarthi]

Apache Airflow version

main (development)

If "Other Airflow 2 version" selected, which one?

No response

What happened?

While trying to use HITL feature with FAB auth manager I see below error. The selected option is saved but during response expects user_id to be str but get_id in FAB auth manager returns an int which causes pydantic error and the request is retried to give conflict response. All auth managers return str except fab.

rg 'def get_id\(' | rg -v test
airflow-core/src/airflow/api_fastapi/auth/managers/models/base_user.py:    def get_id(self) -> str: ...
airflow-core/src/airflow/api_fastapi/auth/managers/simple/user.py:    def get_id(self) -> str:
providers/keycloak/src/airflow/providers/keycloak/auth_manager/user.py:    def get_id(self) -> str:
providers/fab/src/airflow/providers/fab/auth_manager/models/__init__.py:    def get_id(self):
providers/amazon/src/airflow/providers/amazon/aws/auth_manager/user.py:    def get_id(self) -> str:

[2025-08-09T09:31:43.593+0530] {httptools_impl.py:414} ERROR - Exception in ASGI application

Traceback (most recent call last):
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/uvicorn/protocols/http/httptools_impl.py", line 409, in run_asgi
    result = await app(  # type: ignore[func-returns-value]
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/uvicorn/middleware/proxy_headers.py", line 60, in __call__
    return await self.app(scope, receive, send)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/fastapi/applications.py", line 1054, in __call__
    await super().__call__(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/applications.py", line 112, in __call__
    await self.middleware_stack(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/middleware/errors.py", line 187, in __call__
    raise exc
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/middleware/errors.py", line 165, in __call__
    await self.app(scope, receive, _send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/middleware/gzip.py", line 20, in __call__
    await responder(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/middleware/gzip.py", line 39, in __call__
    await self.app(scope, receive, self.send_with_gzip)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/middleware/cors.py", line 93, in __call__
    await self.simple_response(scope, receive, send, request_headers=headers)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/middleware/cors.py", line 144, in simple_response
    await self.app(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/middleware/exceptions.py", line 62, in __call__
    await wrap_app_handling_exceptions(self.app, conn)(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/_exception_handler.py", line 53, in wrapped_app
    raise exc
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/_exception_handler.py", line 42, in wrapped_app
    await app(scope, receive, sender)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/routing.py", line 715, in __call__
    await self.middleware_stack(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/routing.py", line 735, in app
    await route.handle(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/routing.py", line 288, in handle
    await self.app(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/routing.py", line 76, in app
    await wrap_app_handling_exceptions(app, request)(scope, receive, send)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/_exception_handler.py", line 53, in wrapped_app
    raise exc
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/_exception_handler.py", line 42, in wrapped_app
    await app(scope, receive, sender)
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/routing.py", line 73, in app
    response = await f(request)
               ^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/fastapi/routing.py", line 302, in app
    raw_response = await run_endpoint_function(
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/fastapi/routing.py", line 215, in run_endpoint_function
    return await run_in_threadpool(dependant.call, **values)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/starlette/concurrency.py", line 37, in run_in_threadpool
    return await anyio.to_thread.run_sync(func)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/anyio/to_thread.py", line 56, in run_sync
    return await get_async_backend().run_sync_in_worker_thread(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/anyio/_backends/_asyncio.py", line 2461, in run_sync_in_worker_thread
    return await future
           ^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/anyio/_backends/_asyncio.py", line 962, in run
    result = context.run(func, *args)
             ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/airflow-core/src/airflow/api_fastapi/core_api/routes/public/hitl.py", line 218, in update_mapped_ti_hitl_detail
    return _update_hitl_detail(
           ^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/airflow-core/src/airflow/api_fastapi/core_api/routes/public/hitl.py", line 126, in _update_hitl_detail
    return HITLDetailResponse.model_validate(hitl_detail_model)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/karthikeyan/stuff/python/airflow/.venv/lib/python3.11/site-packages/pydantic/main.py", line 703, in model_validate
    return cls.__pydantic_validator__.validate_python(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
pydantic_core._pydantic_core.ValidationError: 1 validation error for HITLDetailResponse
user_id
  Input should be a valid string [type=string_type, input_value=1, input_type=int]
    For further information visit https://errors.pydantic.dev/2.11/v/string_type

What you think should happen instead?

No response

How to reproduce

1. Configure FAB auth manager.
2. Run example_hitl_operator dag.

Operating System

Ubuntu 20.04.3

Versions of Apache Airflow Providers

No response

Deployment

Virtualenv installation

Deployment details

No response

Anything else?

No response

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[tirkarthi]

cc: @vincbeck @Lee-W

[Abhishek1559]

I am working on this, can you assign this to me?

[Lee-W]

Make more sense to change the fab end for me, but I'm not that familiar with fab itself 🤔

---

@Abhishek1559 just assigned to you

[Abhishek1559]

Hi @Lee-W,

That is correct, at FAB end, the function which is implemented from same BaseUser class,
(where it is defined as def get_id(self) -> str: ...) is defined as def get_id(self): return self.id (located at providers/fab/src/airflow/providers/fab/auth_manager/models/init.py).

There is no valid return type annotation mentioned as compared to implementation for other Auth services (ex. Amazon Auth manager, Simple auth, etc) where it is clearly defined with the return type annotations as string.

Although it would not force a String value, it will make the code consistent across the code base.

We can also have str(self.id) as the returning value.

Should I go ahead and raise a PR with the same by adding the type annotation (or also include the type conversion as suggested)?

[Lee-W]

might worth waiting for @vincbeck 's confirmation before actually implementing it, but I think it's the right way to go :)