How to detect "stale" items and groups in RSSL.

Joe.Ferraro

When migrating logic from SSL to RSSL (using UPA/ETA), there is logic in the SSL application that will detect when either a group or an item has become "STALE". These are delivered when SSL_(ITEM|GROUP)_STATUS_TYPE is set to SSL_ET_(ITEM|GROUP)_STATUS_STATLE.

Looking at the logs in the application and correlating them with the EED, it appears that this event is sent to the application when the EED loses its upstream connection -- possibly indicating that there could be a gap in the data.

I can't find a way to receive similar notifications in ETA (or UPA).

Does such a notification event exist?

If not, how can the downstream application be notified that there may be a possible gap in the data?

umer.nalla

Hi @Joe.Ferraro

Have not tested any scenarios around GROUP status, however, my understanding is that GROUP status information is delivered via the Source Directory responses.

You would need to set the RDM_DIRECTORY_SERVICE_GROUP_FILTER when encoding your Source Directory Request.

You should be able to find more information in the RMDUsageGuide and the ETAC DevGuide has a section 13.4 on Item Group use

Item Group Use

Source Directory Group Filter Entry

For individual items going stale, you would expect to see a streamState of Open and a dataState of the item as Suspect - either in a Status Message (when the item becomes stale) or as part of the Refresh Msg (if the item is stale at the point when your Request is received by the provider)

if (pState->streamState == RSSL_STREAM_OPEN && pState->dataState == RSSL_DATA_SUSPECT)
{
/* Stream State is (1) Open (typically implies that information will be streaming, as information changes updated
* information will be sent on the stream, after final RsslRefreshMsg or RsslStatusMsg)
 *
 * Data State is (2) Data is Suspect (similar to a stale data state, indicates that the health of some or all data associated with the stream
 * is out of date or cannot be confirmed that it is current )
 */
printf("\nLogin stream is suspect\n");
return RSSL_RET_FAILURE;
}