Function custom 

pub fn custom<Incoming, Store, Executor, Logger, CommError>(
    server_params: ServerParams<Incoming, Store, Executor, Logger>,
) -> impl Future<Item = (), Error = HandlingError<Incoming::Error>>
where
    Incoming: Stream,
    Incoming::Item: 'static + Stream<Item = Request, Error = CommError> + Sink<SinkItem = Response, SinkError = CommError> + Send,
    Store: 'static + Storage + Clone + Send,
    Executor: Executor<Box<dyn Future<Item = (), Error = ()> + Send + 'static>>,
    Logger: Into<Logger>,
    CommError: 'static,

Creates a server with custom client stream.

This may be used if one wants control over how the messages are serialized. If you want to use the default serialization (length-delimited json encoding), use serve() function.