As reported during a review of
NIFI-3594 / PR 1686, Yolanda M. Davis was able to generate some unhelpful stacktraces and UI error dialogs when switching from PersistentProvenanceRepository (the legacy implementation that most users have selected) to the new EncryptedWriteAheadProvenanceRepository. I had only tested WriteAheadProvenanceRepository to and from EncryptedWriteAheadProvenanceRepository.
In addition, switching between EWAPR and WAPR causes a small exception but the application functions as expected with the exception that previously written provenance events are no longer available. However, when switching from PPR to EWAPR, new provenance events are not written or queryable. This is obviously untenable moving forward.
For now, documentation has been provided explaining that existing repositories must be deleted from disk before switching implementations to allow continued indexing and querying under the new implementation.
The user experience should be improved to suppress the stacktrace and error dialogs and smoothly handle the migration.