Function spawn_fut 

pub async fn spawn_fut<St, Sv>(
    stream: St,
    service: Sv,
    controller: Controller,
) -> Result<(), BoxError>
where
    St: AsyncReadExt + AsyncWriteExt + Unpin + Send + 'static,
    Sv: Service<BytesMut, Response = BytesMut, Error = Error> + Send + 'static,
    Sv::Future: Send,

Spawns a future to handle streams of requests (e.g. a tcp stream).

Errors

Will return Err if failed to read bytes from stream or send bytes to stream.