Event handling in AEMaaCS / Run Java code after publish

[dylanmccurry]

What is the best way to tap into and run a bit of Java code whenever a publish occurs in AEMaaCS?

I have an API servlet that is fetching and returning some structured content from AEM. This servlet uses Caffeine to cache some computations in memory for an hour so that results don't get recomputed on every request. When a publish occurs in AEM, I want to run a function to clear this cache.

I tried the following but it doesn't appear to get triggered (at least locally). What's the best way to trigger a bit of Java code to run after a publish occurs?

@component(service = EventHandler.class, property = {
        EventConstants.EVENT_TOPIC + "=com/adobe/granite/content/replication/end"
})
public class CustomPublishEvent implements EventHandler {
    @reference
    public ResourceResolverFactory rrFactory;

    @Override
    public void handleEvent(Event event) {
        // do something here...
    }
}

[Tethich · Accepted solution]

Hi @dylanmccurry 

Have you already checked this thread https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/replication-event-listener... ? Maybe you find something useful there.

[konstantyn_diachenko]

Yes, I can confirm that solution in mentioned thread works fine for my client.

[dylanmccurry]

I gained some insights from that thread and others. The issue was the event topic was incorrect.

To trigger the event on the publisher, you need to subscribe to a different topic:

import org.osgi.service.event.Event;
import org.osgi.service.event.EventConstants;

import com.day.cq.replication.ReplicationAction;
import com.day.cq.replication.ReplicationActionType;
import com.day.cq.replication.ReplicationEvent;

@Component(service = EventHandler.class,
        immediate = true,
        property = {
                EventConstants.EVENT_TOPIC + "=" + ReplicationEvent.EVENT_TOPIC
        }
)
public class MyPublishEvent implements EventHandler {
    @Override
    public void handleEvent(Event event) {

    }
}