docs: private Message prepare(String channel, Message message, Recipient[] recipients) {
          message.setMetadata("cwf.pub.node", nodeId);
          message.setMetadata("cwf.pub.channel", channel);
          message.setMetadata("cwf.pub.event", UUID.randomUUID().toString());
          message.setMetadata("cwf.pub.when", System.currentTimeMillis());
          message.setMetadata("cwf.pub.recipients", recipients);
          return message;
      }