AttributeError when checking for NullBooleanField in schema generator with DRF 3.14

[MHLut]

Describe the bug
DRF removed NullBooleanField between version 3.13.1 and 3.14.0

Class AutoSchema in openapi.py has an instance check for NullBooleanField which results in an AttributeError ("AttributeError when checking for NullBooleanField in schema generator").

To Reproduce
Register schema endpoints and try to open one of the UIs (Swagger or Redoc):

For example

from django.urls import path
from drf_spectacular.views import SpectacularAPIView

app_name = "api"

urlpatterns = [
    path("schema/", SpectacularAPIView.as_view(), name="schema"),
]

Redoc URL will be something like <host>/api/schema/redoc/ if you registered these URLs under /api/. Opening the page shows the Django error page in the browser.

Expected behavior
Remove the NullBooleanCheck for newer versions of DRF, but keep it for older versions.

[miko13]

hopefully the fix pr will be merged soon and there will be a release!

[tfranzel]

Reopening so people can discover this more easily.

The fix #818 is already merged. A new patch release (0.24.1) is coming shortly.

[tfranzel]

0.24.1 just got released. cheers!

[romeopeter]

You may have to update DRF and drf_spectacular