Method poll_ready

http-cache-tower/examples/hyper_basic.rs:39–44

(
        &mut self,
        _cx: &mut Context<'_>,
    )

    >;

    fn poll_ready(
        &mut self,
        _cx: &mut Context<'_>,
    ) -> Poll<Result<(), Self::Error>> {
        Poll::Ready(Ok(()))
    }

    fn call(&mut self, _req: Request<Full<Bytes>>) -> Self::Future {
        let count = self