protected void publishChangeNotice() {
    // notify account changes after successfully update.
    if (notifier == null) {
      logger.warn("Notifier is not provided. Cannot notify other entities interested in account data change.");
    } else if (notifier.publish(ACCOUNT_METADATA_CHANGE_TOPIC, FULL_ACCOUNT_METADATA_CHANGE_MESSAGE)) {
      logger.trace("Successfully published message for account metadata change");
    } else {
      logger.error("Failed to send notification for account metadata change");
      accountServiceMetrics.notifyAccountDataChangeErrorCount.inc();
    }
  }
Return the {@link Notifier}.
@return The {@link Notifier}
ambry-account/src/main/java/com/github/ambry/account/AbstractAccountService.java