2.0 breaks tests for /docs

[WolfgangFahl]

Question

My CI for https://github.com/WolfgangFahl/nicegui_widgets breaks when using latest 2.x version.
I get an stacktrace that is unfortunately uncomprehensible for me. The test is
https://github.com/WolfgangFahl/nicegui_widgets/blob/main/tests/test_webserver.py
which tries to get the /docs default html see https://ngdemo.bitplan.com/docs for the expected result.
The base class for the test is https://github.com/WolfgangFahl/nicegui_widgets/blob/main/ngwidgets/webserver_test.py

which has been running fine for 1 1/2 years now. What might be the cause for the unexpected break?

NiceGUI ready to go on http://localhost:19856
.ss...ERROR:    Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/routing.py", line 700, in lifespan
    await receive()
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/uvicorn/lifespan/on.py", line 137, in receive
    return await self.receive_queue.get()
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/asyncio/queues.py", line 159, in get
    await getter
asyncio.exceptions.CancelledError

Starting test testDemoWebserver, debug=False ...
.http://testserver/docs not found
NiceGUI ready to go on http://localhost:19856
Event loop is closed
  + Exception Group Traceback (most recent call last):
  |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/_utils.py", line 77, in collapse_excgroups
  |     yield
  |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 186, in __call__
  |     async with anyio.create_task_group() as task_group:
  |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/anyio/_backends/_asyncio.py", line 680, in __aexit__
  |     raise BaseExceptionGroup(
  | exceptiongroup.ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception)
  +-+---------------- 1 ----------------
    | Traceback (most recent call last):
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/errors.py", line 165, in __call__
    |     await self.app(scope, receive, _send)
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/sessions.py", line 85, in __call__
    |     await self.app(scope, receive, send_wrapper)
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 185, in __call__
    |     with collapse_excgroups():
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/contextlib.py", line 153, in __exit__
    |     self.gen.throw(typ, value, traceback)
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/_utils.py", line 83, in collapse_excgroups
    |     raise exc
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 187, in __call__
    |     response = await self.dispatch_func(request, call_next)
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/nicegui/storage.py", line 86, in dispatch
    |     response = await call_next(request)
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 163, in call_next
    |     raise app_exc
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 149, in coro
    |     await self.app(scope, receive_or_disconnect, send_no_error)
    |   File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 185, in __call__
    |     with collapse_excgroups():
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/sessions.py", line 85, in __call__
    await self.app(scope, receive, send_wrapper)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 185, in __call__
    with collapse_excgroups():
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/contextlib.py", line 153, in __exit__
    self.gen.throw(typ, value, traceback)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/_utils.py", line 83, in collapse_excgroups
    raise exc
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 187, in __call__
    response = await self.dispatch_func(request, call_next)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/nicegui/storage.py", line 86, in dispatch
    response = await call_next(request)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 163, in call_next
    raise app_exc
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 149, in coro
    await self.app(scope, receive_or_disconnect, send_no_error)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 185, in __call__
    with collapse_excgroups():
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/contextlib.py", line 153, in __exit__
    self.gen.throw(typ, value, traceback)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/_utils.py", line 83, in collapse_excgroups
    raise exc
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 187, in __call__
    response = await self.dispatch_func(request, call_next)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/nicegui/middlewares.py", line 10, in dispatch
    response = await call_next(request)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 163, in call_next
    raise app_exc
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/base.py", line 149, in coro
    await self.app(scope, receive_or_disconnect, send_no_error)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/gzip.py", line 20, in __call__
    await responder(scope, receive, send)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/gzip.py", line 39, in __call__
    await self.app(scope, receive, self.send_with_gzip)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/middleware/exceptions.py", line 62, in __call__
    await wrap_app_handling_exceptions(self.app, conn)(scope, receive, send)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/starlette/_exception_handler.py", line 73, in wrapped_app
    response = await handler(conn, exc)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/nicegui/nicegui.py", line 152, in _exception_handler_404
    with Client(page(''), request=request) as client:
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/nicegui/client.py", line 66, in __init__
    self.outbox = Outbox(self)
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/nicegui/outbox.py", line 28, in __init__
    background_tasks.create(self.loop(), name=f'outbox loop {client.id}')
  File "/opt/hostedtoolcache/Python/3.10.14/x64/lib/python3.10/site-packages/nicegui/background_tasks.py", line 23, in create
    task: asyncio.Task = core.loop.create_task(coroutine, name=name)
  File "uvloop/loop.pyx", line 1426, in uvloop.loop.Loop.create_task
  File "uvloop/loop.pyx", line 703, in uvloop.loop.Loop._check_closed
RuntimeError: Event loop is closed

[python-and-novella]

Do you try to use ui.run(fastapi_docs=True)?
In 2.0, fastapi docs is disabled defaultly.
Maybe it is the reason.

[WolfgangFahl]

https://github.com/zauberzeug/nicegui/releases mentions the change. I have adapted https://github.com/WolfgangFahl/nicegui_widgets/blob/96f5aa60f12ab802bb7b96cd21de28130de55f7c/ngwidgets/webserver.py#L38 accordingly to keep the old behavior as default.