Commands routed to the parent of polymorphic aggregates cause IncompatibleAggregateException

Basic information

• Axon Framework version: 4.6.0 and 4.6.1
• JDK version: 11
• Complete executable reproducer if available (e.g. GitHub Repo): https://github.com/raphael-jungers/axon-polymorphic-aggregate-sample

Steps to reproduce

Using polymorphic aggregates, send a first command to create the child aggregate, then send a command targeting a CommandHandler declared in the parent class.

Expected behaviour

Before 4.6.0, no exception were raised and the command handler was successfully called.

Actual behaviour

Since 4.6.0, an IncompatibleAggregateException is raised.

The behavior is reproduced in the github repository, here is the stacktrace :

org.axonframework.eventsourcing.IncompatibleAggregateException: Aggregate identifier must be non-null after applying an event. Make sure the aggregate identifier is initialized at the latest when handling the creation event. at org.axonframework.eventsourcing.EventSourcedAggregate.publish(EventSourcedAggregate.java:256) ~[axon-eventsourcing-4.6.0.jar:4.6.0] at org.axonframework.eventsourcing.EventSourcedAggregate$$Lambda$1660.0000000000000000.accept(Unknown Source) ~[na:na] at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133) ~[na:na] at org.axonframework.eventsourcing.EventSourcedAggregate.lambda$initializeState$0(EventSourcedAggregate.java:284) ~[axon-eventsourcing-4.6.0.jar:4.6.0] at org.axonframework.eventsourcing.EventSourcedAggregate$$Lambda$1657.0000000000000000.accept(Unknown Source) ~[na:na] at org.axonframework.modelling.command.inspection.AnnotatedAggregate.lambda$execute$2(AnnotatedAggregate.java:349) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.inspection.AnnotatedAggregate$$Lambda$1658.0000000000000000.run(Unknown Source) ~[na:na] at org.axonframework.modelling.command.AggregateLifecycle.lambda$execute$0(AggregateLifecycle.java:189) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.AggregateLifecycle$$Lambda$1659.0000000000000000.call(Unknown Source) ~[na:na] at org.axonframework.messaging.Scope.executeWithResult(Scope.java:111) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.AggregateLifecycle.execute(AggregateLifecycle.java:188) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.inspection.AnnotatedAggregate.execute(AnnotatedAggregate.java:349) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.eventsourcing.EventSourcedAggregate.initializeState(EventSourcedAggregate.java:281) ~[axon-eventsourcing-4.6.0.jar:4.6.0] at org.axonframework.eventsourcing.EventSourcingRepository.doLoadAggregate(EventSourcingRepository.java:156) ~[axon-eventsourcing-4.6.0.jar:4.6.0] at org.axonframework.eventsourcing.EventSourcingRepository.lambda$doLoadWithLock$1(EventSourcingRepository.java:136) ~[axon-eventsourcing-4.6.0.jar:4.6.0] at org.axonframework.eventsourcing.EventSourcingRepository$$Lambda$976.000000005F7542F0.get(Unknown Source) ~[na:na] at org.axonframework.tracing.Span.runSupplier(Span.java:134) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.eventsourcing.EventSourcingRepository.doLoadWithLock(EventSourcingRepository.java:136) ~[axon-eventsourcing-4.6.0.jar:4.6.0] at org.axonframework.eventsourcing.EventSourcingRepository.doLoadWithLock(EventSourcingRepository.java:55) ~[axon-eventsourcing-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.LockingRepository.doLoad(LockingRepository.java:137) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.LockingRepository.doLoad(LockingRepository.java:60) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.AbstractRepository.lambda$null$6(AbstractRepository.java:141) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.AbstractRepository$$Lambda$946.000000005F7133C0.apply(Unknown Source) ~[na:na] at java.base/java.util.HashMap.computeIfAbsent(HashMap.java:1133) ~[na:na] at org.axonframework.modelling.command.AbstractRepository.lambda$load$8(AbstractRepository.java:140) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.AbstractRepository$$Lambda$945.000000005F6F6C20.get(Unknown Source) ~[na:na] at org.axonframework.tracing.Span.runSupplier(Span.java:134) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.AbstractRepository.load(AbstractRepository.java:137) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.AggregateAnnotationCommandHandler$AggregateCommandHandler.handle(AggregateAnnotationCommandHandler.java:561) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.modelling.command.AggregateAnnotationCommandHandler$AggregateCommandHandler.handle(AggregateAnnotationCommandHandler.java:550) ~[axon-modelling-4.6.0.jar:4.6.0] at org.axonframework.messaging.DefaultInterceptorChain.proceed(DefaultInterceptorChain.java:57) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.messaging.interceptors.CorrelationDataInterceptor.handle(CorrelationDataInterceptor.java:67) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.messaging.DefaultInterceptorChain.proceed(DefaultInterceptorChain.java:55) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.SimpleCommandBus$$Lambda$1225.0000000000000000.call(Unknown Source) ~[na:na] at org.axonframework.messaging.unitofwork.DefaultUnitOfWork.executeWithResult(DefaultUnitOfWork.java:77) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.SimpleCommandBus.lambda$handle$3(SimpleCommandBus.java:198) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.SimpleCommandBus$$Lambda$858.000000005E701000.run(Unknown Source) ~[na:na] at org.axonframework.tracing.Span.run(Span.java:72) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.SimpleCommandBus.handle(SimpleCommandBus.java:189) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.SimpleCommandBus.doDispatch(SimpleCommandBus.java:163) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.SimpleCommandBus.dispatch(SimpleCommandBus.java:130) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.gateway.AbstractCommandGateway.send(AbstractCommandGateway.java:76) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.gateway.DefaultCommandGateway.send(DefaultCommandGateway.java:83) ~[axon-messaging-4.6.0.jar:4.6.0] at org.axonframework.commandhandling.gateway.DefaultCommandGateway.sendAndWait(DefaultCommandGateway.java:100) ~[axon-messaging-4.6.0.jar:4.6.0] at com.example.apas.BugSample.run(BugSample.java:52) ~[classes/:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na] at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na] at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na] at org.springframework.context.event.ApplicationListenerMethodAdapter.doInvoke(ApplicationListenerMethodAdapter.java:344) ~[spring-context-5.3.23.jar:5.3.23] at org.springframework.context.event.ApplicationListenerMethodAdapter.processEvent(ApplicationListenerMethodAdapter.java:229) ~[spring-context-5.3.23.jar:5.3.23] at org.springframework.context.event.ApplicationListenerMethodAdapter.onApplicationEvent(ApplicationListenerMethodAdapter.java:166) ~[spring-context-5.3.23.jar:5.3.23] at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:176) ~[spring-context-5.3.23.jar:5.3.23] at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:169) ~[spring-context-5.3.23.jar:5.3.23] at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:143) ~[spring-context-5.3.23.jar:5.3.23] at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:421) ~[spring-context-5.3.23.jar:5.3.23] at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:378) ~[spring-context-5.3.23.jar:5.3.23] at org.springframework.boot.context.event.EventPublishingRunListener.ready(EventPublishingRunListener.java:114) ~[spring-boot-2.7.5.jar:2.7.5] at org.springframework.boot.SpringApplicationRunListeners.lambda$ready$6(SpringApplicationRunListeners.java:82) ~[spring-boot-2.7.5.jar:2.7.5] at org.springframework.boot.SpringApplicationRunListeners$$Lambda$853.000000005F557250.accept(Unknown Source) ~[na:na] at java.base/java.util.ArrayList.forEach(ArrayList.java:1540) ~[na:na] at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:120) ~[spring-boot-2.7.5.jar:2.7.5] at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:114) ~[spring-boot-2.7.5.jar:2.7.5] at org.springframework.boot.SpringApplicationRunListeners.ready(SpringApplicationRunListeners.java:82) ~[spring-boot-2.7.5.jar:2.7.5] at org.springframework.boot.SpringApplication.run(SpringApplication.java:323) ~[spring-boot-2.7.5.jar:2.7.5] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1306) ~[spring-boot-2.7.5.jar:2.7.5] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1295) ~[spring-boot-2.7.5.jar:2.7.5] at com.example.apas.AxonPolymorphicAggregateSampleApplication.main(AxonPolymorphicAggregateSampleApplication.java:10) ~[classes/:na]

[smcvb]

Happy to hear that, @raphael-jungers! I will reopen the issue for a bit, until the PR is merged. If that’s okay with you, of course.

[raphael-jungers]

Thank you for the quick reply and the bug fix @smcvb ! The fix does work on our real project.