public static String getProperty(Request request, String propertyName) {
    List<String> list = getPropertyList(request, propertyName);
    return list.isEmpty() ? null : list.get(0);
  }
Returns a property from a request
@param request
@param propertyName
@return
ambari-server/src/main/java/org/apache/ambari/server/audit/request/eventcreator/RequestAuditEventCreatorHelper.java