[Python] Having a dependency through Depends() and a schema refer to the same root level key...

I have a situation where I want to authorize the active user against one of the values (Organization) in a FastAPI route. When an object of a particular type is being submitted, one of the keys (organization_id) should be present and the user should be verified as having access to the organization.

I've solved this as a dependency in the API signature to avoid having to replicate this code across all routes that needs access to this property:

def get_organization_from_body(organization_id: str = Body(None),
user: User = Depends(get_authenticated_user),
organization_service: OrganizationService = Depends(get_organization_service),
) -> Organization:
if not organization_id:
raise HTTPException(status_code=400, detail='Missing organization_id.')

organization = organization_service.get_organization_for_user(organization_id, user)

if not organization:
raise HTTPException(status_code=403, detail='Organization authorization failed.')

return organization


This works fine, and if the API endpoint expects an organization through an organization_id key in the request, I can get the organization directly populated by introducing get_organization_from_body as a dependency in my route:

@router.post('', response_model=Bundle)
async def create_bundle([...]
organization: Organization = Depends(get_organization_from_body),
) -> Model:



...and if the user doesn't have access to the organization, an 403 exception is raised.

However, I also want to include my actual object on the root level through a schema model. So my first attempt was to make a JSON request as:

{
'name': generated_name,
'organization_id': created_organization['id_key']
}


And then adding my incoming Pydantic model:

@router.post('', response_model=Bundle)
async def create_bundle(bundle: BundleCreate,
organization: Organization = Depends(get_organization_from_body),
[...]
) -> BundleModel:
[...]
return bundle


The result is the same whether the pydantic model / schema contains organization_id as a field or not:

class BundleBase(BaseModel):
name: str

class Config:
orm_mode = True


class BundleCreate(BundleBase):
organization_id: str
client_id: Optional[str]


.. but when I introduce my get_organization_from_body dependency, FastAPI sees that I have another dependency that refers to a Body field, and the description of the bundle object has to be moved inside a bundle key instead (so instead of "validating" the organization_id field, the JSON layout needs to change - and since I feel that organization_id is part of the bundle description, it should live there .. if possible).

The error message tells me that bundle was expected as a separate field:

{'detail': [{'loc': ['body', 'bundle'], 'msg': 'field required', 'type': 'value_error.missing'}]}


And rightly so, when I move name inside a bundle key instead:

{
'bundle': {
'name': generated_name,
},
'organization_id': created_organization['id_key']
}


...my test passes and the request is successful.

This might be slightly bike shedding, but if there's a quick fix to work around this limitation in any way I'd be interested to find a way to both achieve validation (either through Depends() or in some alternative way without doing it explicitly in each API route function that requires that functionality) and a flat JSON layout that matches my output format closer.

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