[IMPROVEMENT] Use swagger_ui_init_oauth parameter of original function app for versioned /docs (e.g. /v1/docs)

[stoney95]

Subject of the issue

I use swagger_ui_init_oauth when creating the FastAPI instance. This allows me to use the set values when using the "Authorize" feature of the swagger UI. This is very handy as it allows to set the client id and scopes.

I use it like this:

fastapi_app = FastAPI(
    swagger_ui_parameters={"supportedSubmitMethods": allowed_http_methods},
    swagger_ui_init_oauth={
        "clientId": "my-client-id",
        "scopes": "required_scopes",
    },
)

versions = Versionizer(
     app=fastapi_app,
     prefix_format='/v{major}',
     semantic_version_format='{major}',
     latest_prefix='/latest',
     sort_routes=True
).versionize()

Applying the Versionizer does remove the values in versioned docs. It would be great if they are kept.
When accessing "example.com/docs" I can see "my-client-id" is set. But when accessing "example.com/v1/docs" I can't see the client id in the Authorize feature.

Screenshots for further details:

• Authorize Feature

• Client id is set in root docs

• Client id is not set in versioned docs

Your environment

• 3.9.16
• MacOS 13.2.1

Steps to reproduce

from fastapi import FastAPI
from fastapi_versionizer import Versionizer
from fastapi.openapi.models import OAuthFlowImplicit, OAuthFlows
from fastapi.security import OAuth2

oauth2_scheme = OAuth2(
    flows=OAuthFlows(
        implicit=OAuthFlowImplicit(
            authorizationUrl="https://login.microsoftonline.com/oauth2/v2.0/authorize",
        )
    ),
    auto_error=True,
)

fastapi_app = FastAPI(
    swagger_ui_init_oauth={
        "clientId": "my-client-id",
        "scopes": "required_scopes",
    },
)

versions = Versionizer(
     app=fastapi_app,
     prefix_format='/v{major}',
     semantic_version_format='{major}',
     latest_prefix='/latest',
     sort_routes=True
).versionize()

router = APIRouter(prefix="/test")

def check_token(token: Depends(oauth2_scheme)):
    print(token)

@router.get("", dependencies=[Depends(check_token)])
def print_test():
    print("test")

Expected behaviour

I can use the Authorize feature in the versioned docs.

Actual behaviour

The values initialized with swagger_ui_init_oauth are not available in versioned docs (example.com/v1/docs)

[alexschimpf]

Sure, I'll whip up a fix for this soon and let you know. Thanks for finding this!

[alexschimpf]

Alright, this should now be fixed in v3.0.2. Please let me know if you find any other problems.

[stoney95]

@alexschimpf, Thanks for taking care of that issue so quickly!

Now I am able to see the client-id in the Authorize feature. I also tested it with our setup. I get forwarded to the right login page and can login in there -> scopes are also set correctly.

But this runs into another issue. The redirect url cannot be found. This happens with the root docs (/docs) as well as with the versioned docs (/v1/docs). It appears as the Versionizer overwrites / adjusts the swagger_ui_oauth2_redirect_url which defaults to "/docs/oauth2-redirect".

When trying to login via the "Authorize" button I see the following

This refers to a login I did via the root docs

[alexschimpf]

Ok I'll try to look into this once I get a chance

[alexschimpf]

Ah okay. I think I see the issue. For the main docs page, it happens because the redirect route is being stripped out in the _strip_routes function. Then it's not getting added to the versioned docs because the redirect route is not of type APIRoute and is thus getting ignored.

Let me try to get a fix out for this.

[stoney95]

@alexschimpf Thanks for taking care of it :)

[stoney95]

@alexschimpf are there any updates on this?

[alexschimpf]

Sorry for the delay. I need to get back to this. I had a solution mostly written some time ago, but never got around to pushing it. Hopefully I can get something pushed this week.

[alexschimpf]

@stoney95 I think this PR should do this trick: #50
Could you check this to see if the behavior is expected?

If so, I'll add some extra tests and whatnot.

[stoney95]

@alexschimpf, a happy new year to you!

Thanks for providing the fix. I ran some local tests and the issues from above are resolved 🚀

[alexschimpf]

Sorry for the long (ok, very long) delay. Been a busy bee. This fix is available in v4.0.1.