IN - the type of the received dataOUT - the type of replied datapublic interface ReactorChannelHandler<IN,OUT,CONN extends ReactorChannel<IN,OUT>>
extends reactor.fn.Function<CONN,org.reactivestreams.Publisher<java.lang.Void>>
ReactorChannel callback that is attached on ReactorPeer or ReactorClient initialization and receives
all connected ReactorChannel. The Function.apply(T) implementation must return a Publisher to complete or error
in order to close the ReactorChannel.