Bug:App with RabbitBroker fails in v0.5.25

[hoelzl]

Instantiating a FastStream instance with a RabbitBroker fails in version 0.5.25:

How to reproduce

from faststream import FastStream
from faststream.rabbit import RabbitBroker

broker = RabbitBroker("amqp://guest:guest@localhost/")
app = FastStream(broker)

Expected behavior
app is a valid object

Observed behavior
I get the following error:

In [1]: from faststream import FastStream
   ...: from faststream.rabbit import RabbitBroker
   ...:
   ...: broker = RabbitBroker("amqp://guest:guest@localhost/")
   ...: app = FastStream(broker)
---------------------------------------------------------------------------
AsyncLibraryNotFoundError                 Traceback (most recent call last)
Cell In[1], line 5
      2 from faststream.rabbit import RabbitBroker
      4 broker = RabbitBroker("amqp://guest:guest@localhost/")
----> 5 app = FastStream(broker)

File /opt/conda/lib/python3.11/site-packages/faststream/_internal/application.py:74, in Application.__init__(self, broker, logger, lifespan, title, version, description, terms_of_service, license, contact, tags, external_docs, identifier, on_startup, after_startup, on_shutdown, after_shutdown)
     50 def __init__(
     51     self,
     52     broker: Optional["BrokerUsecase[Any, Any]"] = None,
   (...)
     70     after_shutdown: Sequence[Callable[P_HookParams, T_HookReturn]] = (),
     71 ) -> None:
     72     context.set_global("app", self)
---> 74     self._should_exit = anyio.Event()
     75     self.broker = broker
     76     self.logger = logger

File /opt/conda/lib/python3.11/site-packages/anyio/_core/_synchronization.py:79, in Event.__new__(cls)
     78 def __new__(cls) -> Event:
---> 79     return get_asynclib().Event()

File /opt/conda/lib/python3.11/site-packages/anyio/_core/_eventloop.py:147, in get_asynclib(asynclib_name)
    145 def get_asynclib(asynclib_name: str | None = None) -> Any:
    146     if asynclib_name is None:
--> 147         asynclib_name = sniffio.current_async_library()
    149     modulename = "anyio._backends._" + asynclib_name
    150     try:

File /opt/conda/lib/python3.11/site-packages/sniffio/_impl.py:93, in current_async_library()
     90     if curio_running():
     91         return 'curio'
---> 93 raise AsyncLibraryNotFoundError(
     94     "unknown async library, or not in async context"
     95 )

AsyncLibraryNotFoundError: unknown async library, or not in async context

Additional context
This is probably due to #1683.

[Lancetnik]

It is interesting, could you please provide information about faststream, anyio versions and your platform?

Just an output of faststream --version command and anyio

[Lancetnik]

Are you really using curio? With default setup your example works as expected