Function hyper::server::shutdown::on_drain

source ยท 
fn on_drain<I, S, E>(conn: Pin<&mut UpgradeableConnection<I, S, E>>)
where
    S: HttpService<Body>,
    S::Error: Into<Box<dyn StdError + Send + Sync>>,
    I: AsyncRead + AsyncWrite + Unpin,
    S::ResBody: HttpBody + 'static,
    <S::ResBody as HttpBody>::Error: Into<Box<dyn StdError + Send + Sync>>,
    E: ConnStreamExec<S::Future, S::ResBody>,