decodeControlPayload method
Builds a message from a relayed JSON payload.
Implementation
@override
StringMessage? decodeControlPayload(Object payload) {
if (payload is! String) return null;
return MessageFactory.stringMessage(
data: IList([payload]),
channels: 1,
// Only the local half. The control path is JSON with no envelope to hang
// a sender clock on, so the sender stamps one inside the coordination
// payload instead and the controller pairs the two up. See
// CoordinationMessage.senderClockKey.
timing: MessageTiming(receivedClock: PeerClock.now()),
);
}