diff --git a/java/outbox.md b/java/outbox.md index 7a400f983..48fd8602d 100644 --- a/java/outbox.md +++ b/java/outbox.md @@ -355,29 +355,71 @@ It is crucial to make the service `OutboxDeadLetterQueueService` accessible for ::: -### Filter for Dead Entries +### Reading Dead Entries -This filtering can't be done on the database since the maximum number of attempts is only available from the CDS properties. - -To ensure that only dead outbox entries are returned when reading `DeadOutboxMessages`, the following code provides the handler for the `DeadLetterQueueService` and the `@After-READ` handler that filters for the dead outbox entries: +This filtering of dead entries are done on the database by adding `where` clauses for each outbox and their maximum number of retries. The following code provides the handler for the `DeadLetterQueueService` that reads the dead entries directly from the entity `Messages`: ```java @Component @ServiceName(OutboxDeadLetterQueueService_.CDS_NAME) public class DeadOutboxMessagesHandler implements EventHandler { - @After(entity = DeadOutboxMessages_.CDS_NAME) - public void filterDeadEntries(CdsReadEventContext context) { - CdsProperties.Outbox outboxConfigs = context.getCdsRuntime().getEnvironment().getCdsProperties().getOutbox(); - List deadEntries = context - .getResult() - .listOf(DeadOutboxMessages.class) - .stream() - .filter(entry -> entry.getAttempts() >= outboxConfigs.getService(entry.getTarget()).getMaxAttempts()) - .toList(); - - context.setResult(deadEntries); - } + private final PersistenceService db; + + public DeadOutboxMessagesHandler(@Qualifier(PersistenceService.DEFAULT_NAME) PersistenceService db) { + this.db = db; + } + + @On(service = PersistenceService.DEFAULT_NAME, entity = DeadOutboxMessages_.CDS_NAME) + public void readDeadOutboxMessages(CdsReadEventContext context) { + Optional outboxFilters = this.createOutboxFilters(context.getCdsRuntime()); + CqnSelect cqn = context.getCqn(); + Select> select = Select + .from(Messages_.CDS_NAME) + .columns(cqn.items()); + + select = select.groupBy(cqn.groupBy()); + select = select.excluding(cqn.excluding()); + if(cqn.having().isPresent()) { + select = select.having(cqn.having().get()); + } + if(cqn.search().isPresent()) { + select.search(cqn.search().get()); + } + if(cqn.where().isPresent()) { + CqnPredicate where = cqn.where().get(); + if (outboxFilters.isPresent()) { + where = outboxFilters.get().and(where); + } + select = select.where(where); + } else if (outboxFilters.isPresent()) { + select = select.where(outboxFilters.get()); + } + select = select.orderBy(cqn.orderBy()).limit(cqn.top(), cqn.skip()).inlineCount(); + + List deadMessages = this.db.run(select).list(); + context.setResult(ResultBuilder.selectedRows(deadMessages).inlineCount(deadMessages.size()).result()); + } + + private Optional createOutboxFilters(CdsRuntime runtime) { + List outboxServices = runtime.getServiceCatalog().getServices(OutboxService.class) + .filter(s -> !s.getName().equals(OutboxService.INMEMORY_NAME)).toList(); + CdsProperties.Outbox outboxConfigs = runtime.getEnvironment().getCdsProperties().getOutbox(); + + Predicate where = null; + for(OutboxService service : outboxServices) { + OutboxServiceConfig config = outboxConfigs.getService(service.getName()); + Predicate targetPredicate = CQL.get(Messages.TARGET).eq(service.getName()).and(CQL.get(Messages.ATTEMPTS).ge(config.getMaxAttempts())); + + if (where == null) { + where = targetPredicate; + } else { + where = where.or(targetPredicate); + } + } + + return Optional.ofNullable(where); + } } ```