Function catcher

tests/test_ws_router.py:217–222

(websocket, call_next)

    @websocket_middleware
    async def catcher(websocket, call_next):
        try:
            return await call_next()
        except Exception as e:  # pragma: no cover
            caught.append(e)
            raise

    myapp = make_app(middleware=[Middleware(catcher)])