ACTIV Topic subscription states.
The topic subscription state identifies the current state of a topic with topic type TopicType.map
pendingThe initial state for a subscription during setup, this state will not normally be seen by clients.
synchronizingA synchronization state is used for topics that are of type map
okThe topic is subscribed and valid, no gaps have been detected since the last refresh message
gapA gap or failover has been detected for a topic, whilst any subsequent update message may be used there may have been missing updates and any locally stored last value cache should be considered invalid. This state will remain unchanged until a refresh message is received.