the limiter breaks my route and i cant figgure out why

[NoirPi]

Hello everyone...

So i've tried to ask for help in den FastAPI Community first but they couldnt help me figgure out whats going on here.

This is the route im having problems with!

@router.put("/strain/{_id}", status_code=200, summary="Update a strain by its UUID", tags=["strains"])
# @limiter.limit("30/minute;120/hour")
async def update_strain_by_id(request: Request, _id: int, update_data: CannabisStrain,
                              current_user: User = Depends(get_current_active_user)) -> JSONResponse:

When i remove the limiter the whole route works just fine... but if i add the limiter to this route i get the following error right at startup and then it crashes.

  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\type_adapter.py", line 239, in __init__
    core_schema = _getattr_no_parents(type, '__pydantic_core_schema__')
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\type_adapter.py", line 173, in _getattr_no_parents
    raise AttributeError(attribute)
AttributeError: __pydantic_core_schema__

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_generate_schema.py", line 624, in _resolve_forward_ref
    obj = _typing_extra.evaluate_fwd_ref(obj, globalns=self._types_namespace)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_typing_extra.py", line 425, in evaluate_fwd_ref
    return ref._evaluate(globalns=globalns, localns=localns, recursive_guard=frozenset())
  File "C:\Program Files\Python310\lib\typing.py", line 694, in _evaluate
    eval(self.__forward_code__, globalns, localns),
  File "<string>", line 1, in <module>
NameError: name 'CannabisStrain' is not defined

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "C:\Program Files\Python310\lib\multiprocessing\process.py", line 315, in _bootstrap
    self.run()
  File "C:\Program Files\Python310\lib\multiprocessing\process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\uvicorn\_subprocess.py", line 76, in subprocess_started
    target(sockets=sockets)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\uvicorn\server.py", line 61, in run
    return asyncio.run(self.serve(sockets=sockets))
  File "C:\Program Files\Python310\lib\asyncio\runners.py", line 44, in run
    return loop.run_until_complete(main)
  File "C:\Program Files\Python310\lib\asyncio\base_events.py", line 646, in run_until_complete
    return future.result()
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\uvicorn\server.py", line 68, in serve
    config.load()
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\uvicorn\config.py", line 467, in load
    self.loaded_app = import_from_string(self.app)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\uvicorn\importer.py", line 21, in import_from_string
    module = importlib.import_module(module_str)
  File "C:\Program Files\Python310\lib\importlib\__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 883, in exec_module
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "E:\Onedrive\Coding\PycharmProjects\CannaPi\main.py", line 16, in <module>
    from Routers.strain_routes import router as strain_router
  File "E:\Onedrive\Coding\PycharmProjects\CannaPi\Routers\strain_routes.py", line 265, in <module>
    async def update_strain_by_id(request: Request, _id: int, update_data: CannabisStrain,
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\fastapi\routing.py", line 928, in decorator
    self.add_api_route(
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\fastapi\routing.py", line 867, in add_api_route
    route = route_class(
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\fastapi\routing.py", line 490, in __init__
    self.dependant = get_dependant(path=self.path_format, call=self.endpoint)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\fastapi\dependencies\utils.py", line 262, in get_dependant
    type_annotation, depends, param_field = analyze_param(
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\fastapi\dependencies\utils.py", line 437, in analyze_param
    field = create_response_field(
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\fastapi\utils.py", line 99, in create_response_field
    return ModelField(**kwargs)  # type: ignore[arg-type]
  File "<string>", line 6, in __init__
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\fastapi\_compat.py", line 107, in __post_init__
    self._type_adapter: TypeAdapter[Any] = TypeAdapter(
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\type_adapter.py", line 241, in __init__
    core_schema = _get_schema(type, config_wrapper, parent_depth=_parent_depth + 1)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\type_adapter.py", line 156, in _get_schema
    schema = gen.generate_schema(type_)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_generate_schema.py", line 452, in generate_schema
    schema = self._generate_schema(obj)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_generate_schema.py", line 684, in _generate_schema
    schema = self._post_process_generated_schema(self._generate_schema_inner(obj))
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_generate_schema.py", line 691, in _generate_schema_inner
    return self._annotated_schema(obj)
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_generate_schema.py", line 1520, in _annotated_schema
    source_type, *annotations = self._get_args_resolving_forward_refs(
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_generate_schema.py", line 648, in _get_args_resolving_forward_refs
    args = tuple([self._resolve_forward_ref(a) if isinstance(a, ForwardRef) else a for a in args])
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_generate_schema.py", line 648, in <listcomp>
    args = tuple([self._resolve_forward_ref(a) if isinstance(a, ForwardRef) else a for a in args])
  File "E:\PythonEnvironments\CannaPi\lib\site-packages\pydantic\_internal\_generate_schema.py", line 626, in _resolve_forward_ref
    raise PydanticUndefinedAnnotation.from_name_error(e) from e
pydantic.errors.PydanticUndefinedAnnotation: name 'CannabisStrain' is not defined

So if someone could please explain me what is happening here... i use limiters on all my routes and only this one is making problems...

The "not defined" CannabisStrain is a dataclass

class CannabisStrain:
    id: int
    name: str
    category: List[str] | None = None
    parents: List[str] | None = None
    rating: float | None = None
    effects: List[str] | None = None
    flavor: List[str] | None = None
    description: List[str] | List = None
    thc_level: List[float] | List = None
    cbd_level: List[float] | List = None
    growth_info: Dict[str, str] | None = None
    keywords: str | None = None

[laurentS]

Hello,

I have no immediate idea, but since pydantic seems to be causing the bug...
Your dataclass definition is invalid, attributes description and the next two should probably be List....| None as you set their default value to None.

Not sure why this would break only with slowapi though.

Maybe share how you're initialising Limiter?
My other thought would be that slowapi wraps all your routes in a decorator, maybe that's part of the reason that pydantic isn't happy?

[NoirPi]

So yeah you were right the defintion of the dataclass was incorrect.. But that doesnt fix the issue...

I've tried multiple things there like

@dataclasses.dataclass
class CannabisStrain:
    id: int
    name: str
    category: List[str] = None
    parents: List[str] = None
    rating: float = None
    effects: List[str] = None
    flavor: List[str] = None
    description: List[str] = None
    thc_level: List[float] = None
    cbd_level: List[float] = None
    growth_info: Dict[str, str] = None
    keywords: str = None

all with the same result...

And for your second thought my initalisation of Limiter:

from slowapi import Limiter
from slowapi.util import get_remote_address

limiter = Limiter(key_func=get_remote_address)
app.state.limiter = limiter
app.add_exception_handler(RateLimitExceeded, _rate_limit_exceeded_handler)

The absolute basic example from the Docs no changes at all..