code: static String getDefaultClientName(WarningReporter reporter)
      {
          try {
              return UUID.randomUUID().toString();
          } catch (Exception e) {
              reporter.warn("No client name was set on appender!", e);
              return null;
          }
      }
docs: Get a default client name.
  This is used as a default client ID for Kafka logging.
  WARNING: This is not idempotent. The current implement creates a new random UUID each time this is called.
  
  @param reporter a reporter to send a warning report to if we can't get a client name
  @return the client name