@Override
    protected void buildAuditMessage(StringBuilder builder) {
      super.buildAuditMessage(builder);

      builder
        .append(", Operation(")
        .append(operation);
      if(hostname != null) {
        builder.append("), Host name(").append(hostname);
      }
      builder.append("), RequestId(")
        .append(requestId)
        .append("), Status(")
        .append(reasonOfFailure == null ? "Successfully queued" : "Failed to queue");

      if (reasonOfFailure != null) {
        builder.append("), Reason(")
          .append(reasonOfFailure);
      }
      builder.append(")");
    }
Appends to the audit event the identifier of the
operation through whcih the operation progress can be tracked.

@param builder builder for the audit event details.
ambari-server/src/main/java/org/apache/ambari/server/audit/event/request/StartOperationRequestAuditEvent.java