Function client_async_tls 

pub async fn client_async_tls<R, S>(
    request: R,
    stream: S,
) -> Result<(WebSocketStream<MaybeTlsStream<S>>, Response<Option<Vec<u8>>>), Error>
where
    R: IntoClientRequest,
    S: AsyncRead + AsyncWrite + Unpin + 'static,

Available on crate feature ws only.

Creates a WebSocket handshake from a request and a stream, upgrading the stream to TLS if required.