Risk of memory leak in JpaEventPublicationRepository

[iirekm]

findIncompletePublicationsPublishedBefore and similar methods do something like: entityManager....getResultStream().map(...).toList(). The toList() part here can cause a memory leak if there are zillions of events to process (e.g. the event handler is constantly failing). Paging is missing (e.g. OFFSET...LIMIT)

I had a similar expensive, production bug in custom-made transactional outbox, because of exactly the same problem!

The same problem likely exists in other publication repository implementations (e.g. JDBC).

Another issue I see is order by p.publicationDate asc - after adding paging it will make Denial of Service attacks pretty easy (when all events in a page end with processing error, eventually no further events can be processed). Instead some form of exponential backoff and/or randomness should be used.

Version: 1.3.1