Describe the bug
Class based callable dependencies (https://fastapi.tiangolo.com/advanced/advanced-dependencies/) don't work when used as generators with yield keyword.
To Reproduce
class SessionScope:
def __init__(self, uri):
self.engine = create_engine(uri)
self.session_maker = scoped_session(sessionmaker(bind=self.engine))
def __call__(self):
session = self.session_maker()
try:
yield session
except:
session.rollback()
raise
finally:
self.session_maker.remove()
get_db = SessionScope('postgresql://postgres:[email protected]:5432/my_db')
@router.get('/', response_model=List[User])
def read_users(
db: Session = Depends(get_db),
skip: int = 0,
limit: int = 100,
):
"""
Retrieve users.
"""
users = crud.user.get_multi(db, skip=skip, limit=limit)
return usersExpected behavior
Dependency must return yielded session, but now it returns __call__ generator instance
Additional context
The problem lies in /fastapi/dependencies/utils.py file on line 498:
elif inspect.isgeneratorfunction(call) or inspect.isasyncgenfunction(call):
stack = request.scope.get("fastapi_astack")
if stack is None:
raise RuntimeError(
async_contextmanager_dependencies_error
) # pragma: no cover
solved = await solve_generator(
call=call, stack=stack, sub_values=sub_values
)Paramter call passed to inspect.isgeneratorfunction is instance of a class instead of it's __call__ method and this function always returns False.
Describe the bug
Class based callable dependencies (https://fastapi.tiangolo.com/advanced/advanced-dependencies/) don't work when used as generators with yield keyword.
To Reproduce
Expected behavior
Dependency must return yielded session, but now it returns __call__ generator instance
Additional context
The problem lies in /fastapi/dependencies/utils.py file on line 498:
Paramter call passed to inspect.isgeneratorfunction is instance of a class instead of it's __call__ method and this function always returns False.