ClassCastException with org.apache.sling.distribution.DistributionRequestType in CloudDispatcherFlushRulesExecutor.handleEvent

[shivamrastogi1308]

We are using com.adobe.acs.commons.replication.dispatcher.impl.DispatcherFlushRulesImpl~faq-content-fragment.cfg.json
but with java 21 upgrade deployment we are getting below mentioned error for ClassCastException:

java.lang.ClassCastException: class org.apache.sling.distribution.DistributionRequestType cannot be cast to class java.lang.String (org.apache.sling.distribution.DistributionRequestType is in unnamed module of loader org.apache.felix.framework.BundleWiringImpl$BundleClassLoader @556ef35f; java.lang.String is in module java.base of loader 'bootstrap')
at com.adobe.acs.commons.replication.dispatcher.impl.CloudDispatcherFlushRulesExecutor.handleEvent(CloudDispatcherFlushRulesExecutor.java:63)
at org.apache.felix.eventadmin.impl.handler.EventHandlerProxy.sendEvent(EventHandlerProxy.java:432) [org.apache.felix.eventadmin:1.6.4]
at org.apache.felix.eventadmin.impl.tasks.HandlerTask.runWithoutDenylistTiming(HandlerTask.java:82) [org.apache.felix.eventadmin:1.6.4]
at org.apache.felix.eventadmin.impl.tasks.SyncDeliverTasks.execute(SyncDeliverTasks.java:107) [org.apache.felix.eventadmin:1.6.4]
at org.apache.felix.eventadmin.impl.tasks.AsyncDeliverTasks$TaskExecuter.run(AsyncDeliverTasks.java:167) [org.apache.felix.eventadmin:1.6.4]
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:572)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
at java.base/java.lang.Thread.run(Thread.java:1583)

[kwin]

@royteeuwen Since you contributed this code in

acs-aem-commons/bundle-cloud/src/main/java/com/adobe/acs/commons/replication/dispatcher/impl/CloudDispatcherFlushRulesExecutor.java

Line 63 in 8c395ac

String distributionType = (String) event.getProperty(DISTRIBUTION_TYPE);

have you experienced this as well. This seems to imply it is a String: https://github.com/apache/sling-org-apache-sling-distribution-api/blob/90c4de72ce5b1ba2f95bb17aab748389d1748a7b/src/main/java/org/apache/sling/distribution/event/DistributionEvent.java#L86C19-L86C36 but in fact events emitted from https://github.com/apache/sling-org-apache-sling-distribution-core/blob/04fa537b02bf2579f29fca43100dfdaa641ac938/src/main/java/org/apache/sling/distribution/event/impl/DefaultDistributionEventFactory.java#L57 have a different type.

Maybe relying on https://github.com/apache/sling-org-apache-sling-distribution-api/blob/90c4de72ce5b1ba2f95bb17aab748389d1748a7b/src/main/java/org/apache/sling/distribution/event/DistributionEvent.java#L92 would also make it work with DistributionRequestType. WDYT?

[kwin]

I tried to get some clarification in https://issues.apache.org/jira/browse/SLING-12860.

[royteeuwen]

@kwin Hmm doesn't ring a bell, it definitely (used to) work when I created it and didn't throw any exceptions...

In the meantime, I also think that Adobe re-added the old way to AEMaaCS, namely using replication preprocessors on the flush agents, but I'm not certain and currently not actively involved in a cloud project to investigate on an actual environment instead of only the sdk...