Problem with @EventHandler Cache Projection Event - Repeating Commandding

I have a problem with Axon with Spring Boot + RabbbitMQ.

I currently have a micro service that processes the messages made available by RabbitMQ (which Axon has inserted) and then I do an insert in my Database (postgresql/MongoDB).

So I have three Databases: Normal BD(postgresql), EventStore(Axon), NoSQL(MongoDB)

But if I do a delete of a patient in “postgresql” or “MongoDB”, after my application restarts, as I’m recovering all my inserts that I had already done. I have the impression that it is related to axon events, as axon sees that it doesn’t exist in that database or something like that, it retrieves that event in TrackingEventProcessor and runs again, I would like to have full control of my messages. I understand that events should not be deleted, but my application database would like to have control.

Could you indicate how I can do this?

I’m using the SendAndWait() method to send the commands and in the projection I’m using the framework’s default settings

Hi @renanh.lima,

As you are using an Event Store, you should have another Event which will delete a patient. Having that as part of your events will make sure your projections are not in a different state.


Hi @lfgcampos ,

I have @EventHandler with PatientAddedEvent, PatientUpdatedEvent and PatientDeletedEvent.

And the flow is working normally as expected. Save to Event Store, Normal BD and NoSQL BD. But if I run the deleted event, it will remove it from my database as it’s supposed to and it’s still in my Event Store as it’s supposed to. But the problem is that my @EventHandler method has some kind of cache that executes all my Events again so doing the Insert again, as a kind of cache, I don’t know why, because it shouldn’t be doing. I validated if there is something in RabbitMQ to be processed and it doesn’t. I want to find out where this cache is coming from and why when I restart my application it’s all running again. I don’t have anything in my application.yaml or @Configuration, so I’m using all Axon Framework defaults.

Hi @renanh.lima,

Do you mind sharing an example of this behaviour?
One thing we suspect is that, since you are using Mongo, you haven’t configured a persistent Token Store which will cause a replay of your Event Stream on each restart.

You mentioned that your events are executed again - does it include the PatientDeletedEvent?


So am I supposed to configure Mongo right?

To behave correctly? I’m configuring the exact same thing now to see if the behavior is correct.

Is this the way?

Configuring Mongo might help, yes.
Specially the Token Store, which is an InMemory by default (if nothing is configured).

The ref-guide, as you shared, is a good place to look for that but our mongo-axon-example as well.

Let us know if you need any more help.


I made the settings to work with MongoBD and it’s not writing, just in the “trackingtokens” document, I also noticed that my @EventHandler that worked now aren’t working.


    servers: localhost:8124
    token: 12345
    general: jackson
    events: jackson
    messages: jackson
        source: myQueueMessageSource

Config Class:

public class AxonConfig {

    public EmbeddedEventStore eventStore(EventStorageEngine storageEngine, AxonConfiguration configuration) {
        return EmbeddedEventStore.builder()
                .messageMonitor(configuration.messageMonitor(EventStore.class, "eventStore"))

    public EventStorageEngine storageEngine(MongoClient client) {
        return MongoEventStorageEngine.builder()

    public TokenStore tokenStore(MongoClient client, Serializer serializer) {
        return MongoTokenStore.builder().mongoTemplate(DefaultMongoTemplate.builder().mongoDatabase(client).build()).serializer(serializer).build();


public class RabbitConfig {


    public SpringAMQPMessageSource myQueueMessageSource(AMQPMessageConverter messageConverter) {
        return new SpringAMQPMessageSource(messageConverter) {

            @RabbitListener(queues = "${rabbitmq.queue-cache}")
            public void onMessage(Message message, Channel channel) {
      "amqp event message received");
                super.onMessage(message, channel);

Problem solved, I needed to configure the Aggregate project to send the messages correctly, so that my projection project could identify correctly.

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Glad to hear you solved your issue @renanh.lima, thanks for letting us know!

If there are more questions, feel free to ask.