Bug: type annotation needs local import to work with websocket_listener
Description
I have a bit of a weird issue right now. If I use type annotation of a class without importing the class locally the app will not start, although the forward ref is passed specifically for websocket_listener, regular HTTP handler work.
Currently not a critical issue, but worth checking out I think.
URL to code causing the issue
No response
MCVE
# in the file dummy.py
async def get_dummy() -> "DummyClass":
return DummyClass()
class DummyClass:
def __init__(self) -> None:
self.some_property = "test"
# in the file handler.py
from litestar.di import Provide
from litestar import websocket_listener
from dummy import get_dummy
from typing import TYPE_CHECKING
if TYPE_CHECKING:
from dummy import DummyClass
@websocket_listener("/session/push", dependencies={"dummy_class": Provide(get_dummy)})
async def websocket_dummy(data: str, dummy_class: "DummyClass") -> str:
return dummy_class.some_property
# in the file main.py
from litestar import Litestar
from handler import websocket_dummy
from dummy import DummyClass
app = Litestar(route_handlers=[websocket_dummy], signature_types=[DummyClass])Steps to reproduce
1. Run the app
2. A NameError with name 'DummyClass' is not defined is triggered
3. see Stacktrace in logsScreenshots
""Logs
File "/root/innovation-framework/main.py", line 2, in <module>
from handler import websocket_dummy
File "/root/innovation-framework/handler.py", line 12, in <module>
@websocket_listener("/session/push", dependencies={"dummy_class": Provide(get_dummy)})
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/root/innovation-framework/.venv/lib/python3.12/site-packages/litestar/handlers/websocket_handlers/listener.py", line 230, in __call__
parsed_signature = ParsedSignature.from_fn(fn, self.resolve_signature_namespace())
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/root/innovation-framework/.venv/lib/python3.12/site-packages/litestar/utils/signature.py", line 214, in from_fn
fn_type_hints = get_fn_type_hints(fn, namespace=signature_namespace)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/root/innovation-framework/.venv/lib/python3.12/site-packages/litestar/utils/signature.py", line 167, in get_fn_type_hints
hints = get_type_hints(fn_to_inspect, globalns=namespace, include_extras=True)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/root/innovation-framework/.venv/lib/python3.12/site-packages/typing_extensions.py", line 1230, in get_type_hints
hint = typing.get_type_hints(
^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/typing.py", line 2301, in get_type_hints
hints[name] = _eval_type(value, globalns, localns, type_params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/typing.py", line 415, in _eval_type
return t._evaluate(globalns, localns, type_params, recursive_guard=recursive_guard)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/typing.py", line 938, in _evaluate
eval(self.__forward_code__, globalns, locals_to_pass),
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "<string>", line 1, in <module>
NameError: name 'DummyClass' is not definedLitestar Version
2.9.1
Platform
- Linux
- Mac
- Windows
- Other (Please specify in the description above)
litestar-org / litestar
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