We now allow externalizing application events to a variety of message brokers through the addition of Spring Modulith modules for Kafka, AMQP and JMS to a user project's classpath. Which events shall be externalized and how they're supposed to be routed to the message broker can be configured through either annotations or via a configuration API declared as Spring bean.
In case Jackson is on the classpath, we also add auto-configuration to use a Boot-configured ObjectMapper instance with the corresponding message broker client APIs to properly serialize and deserialize messages to JSON.
Introduce a new spring-modulith-events-api artifact to contain types that are supposed to be used by application code to deal with event publications. `EventPublication` was moved into that artifact and got everything non infrastructure related extracted from it's previous incarnation. That in turn has been renamed to `TargetEventPublication`.
`CompletedEventPublications` exposes API to allow purging completed publications either by a given predicate or age (in `Duration`). The interface is implemented by `DefaultEventPublicationRegistry` and thus subject for dependency injection into user code. It primarily delegates to the corresponding methods on `EventPublicationRepository` adapting the given `Duration`s to the `Clock` instance already held internally.
`IncompleteEventPublications` allows triggering the re-submission of incomplete publications by the same criteria as `CEP`. The interface is implemented by `PersistentApplicationEventMulticaster` and this subject for dependency injection into user code.
`EventPublicationRepository` now also allows publications to be deleted by identifiers. The existing implementations have been adapted and batch the requests for every 100 identifiers to prevent a list too large to run into limitations of the underlying data store.
Polished transactional metadata declaration in JPA- and MongoDB-based repository implementations.
Tightened nullability expressions here and there.
