def rpc(message_name, data=nil, opts={})
      message_name = validated_message_name(message_name)
      publisher.rpc(message_name, data, opts)
    end
def rpc(message_name, data=nil, opts={})
      message_name = validated_message_name(message_name)
      publisher.rpc(message_name, data, opts)
    end
sends the given message to one of the configured servers and returns the result of running the associated handler.

 unexpected behavior can ensue if the message gets routed to more than one recipient, so be careful.