Custom filters

Custom filters

Programmatic filtering is the main addition in 0.1.8. Define the rule once in a reusable class and reference it from any listener annotation. The filter class must be a Spring bean.

@Component
public class ActivePersonFilter extends TentacolousFilter<Person> {

    @Override
    public boolean accept(TentacolousFilterContext<Person> context) {
        Person person = context.getEntity();
        Person oldPerson = context.getOldEntity();

        return person.isActive()
                && (oldPerson == null
                    || !Objects.equals(person.getStatus(), oldPerson.getStatus()));
    }
}

@TentacolousListener(
    entity = Person.class,
    action = ActionListener.UPDATE,
    filter = ActivePersonFilter.class
)
public void onActivePersonUpdated(Person newPerson, Person oldPerson) {
}

Available on every annotation

@TentacolousListener is optional. Existing annotations remain available and now accept the same custom filter:

@UponInserting(entity = Person.class, filter = ActivePersonFilter.class)
public void onPersonInserted(Person person) {
}

@UponUpdating(entity = Person.class, filter = ActivePersonFilter.class)
public void onPersonUpdated(Person newPerson, Person oldPerson) {
}

@UponDeleting(entity = Person.class, filter = ActivePersonFilter.class)
public void onPersonDeleted(Person person) {
}

Annotation	Operation	Custom filter
@UponInserting	INSERT	Supported
@UponUpdating	UPDATE	Supported
@UponDeleting	DELETE	Supported
@TentacolousListener	Selected with action	Supported

getEntity() contains the current payload. getOldEntity() is available for updates and is null for inserts and deletes. The context also exposes getOperation(), getEventId(), getEntityName(), and getRecordKey().

For updates, getChangedFields() returns the changed JSON field names and hasChanged("status") checks one field. Inserts and deletes return an empty set and false.

When filter is configured together with field, valueType, or value, Tentacolous logs a warning. The custom filter has priority and the declarative filter is not executed. Filter errors follow the normal event retry flow.