Query Plugin

It implements the following Persistence Queries:

  • eventsByPersistenceId, currentEventsByPersistenceId
  • eventsByTag, currentEventsByTag
  • persistenceIds, currentPersistenceIds

See API details in CassandraReadJournalCassandraReadJournal and eventsByTag documentation.

Persistence Query usage example to obtain a stream with all events tagged with “someTag” with Persistence Query:

val queries = PersistenceQuery(system).readJournalFor[CassandraReadJournal](CassandraReadJournal.Identifier)
queries.eventsByTag("someTag", Offset.noOffset)

Configuration

The default settings can be changed with the configuration properties defined in reference.conf.

Query configuration is under pekko.persistence.cassandra.query.

Events by tag configuration is under pekko.persistence.cassandra.events-by-tag and shared by journal and query.

If using events by tag query it is important to set the first time bucket