Eventhandler outside aggregate is raising classcastexception on runtime,

Fernando París

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Jul 12, 2017, 10:22:23 AM7/12/17

to Axon Framework Users

Without registerinng events are not received, Grails 3 , boot axon 3.0.5

Can you help me?

Kind regards

ERROR

org.springframework.context.ApplicationContextException: Failed to start bean 'eventHandlerRegistrar'; nested exception is java.lang.ClassCastException: org.springframework.beans.factory.config.MethodInvokingFactoryBean$$EnhancerBySpringCGLIB$$773ccb1d cannot be cast to org.axonframework.eventhandling.EventBus

at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178)

at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:50)

at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:348)

at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:151)

at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:114)

at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:879)

at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.finishRefresh(EmbeddedWebApplicationContext.java:144)

at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:545)

at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122)

at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:762)

at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:372)

at org.springframework.boot.SpringApplication.run(SpringApplication.java:316)

at grails.boot.GrailsApp.run(GrailsApp.groovy:83)

at grails.boot.GrailsApp.run(GrailsApp.groovy:388)

at grails.boot.GrailsApp.run(GrailsApp.groovy:375)

at grails.boot.GrailsApp$run.call(Unknown Source)

at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48)

at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113)

at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:133)

at es.wealth.backoffice.Application.main(Application.groovy:12)

Caused by: java.lang.ClassCastException: org.springframework.beans.factory.config.MethodInvokingFactoryBean$$EnhancerBySpringCGLIB$$773ccb1d cannot be cast to org.axonframework.eventhandling.EventBus

at org.axonframework.spring.config.AxonConfiguration$$EnhancerBySpringCGLIB$$783e9336.eventBus(<generated>)

at org.axonframework.config.EventHandlingConfiguration.subscribingEventProcessor(EventHandlingConfiguration.java:83)

at org.axonframework.config.EventHandlingConfiguration.defaultEventProcessor(EventHandlingConfiguration.java:72)

at org.axonframework.config.EventHandlingConfiguration.lambda$initialize$13(EventHandlingConfiguration.java:332)

at java.util.HashMap.forEach(HashMap.java:1280)

at org.axonframework.config.EventHandlingConfiguration.initialize(EventHandlingConfiguration.java:330)

at org.axonframework.spring.config.EventHandlerRegistrar.start(EventHandlerRegistrar.java:84)

Disconnected from the target VM, address: '127.0.0.1:64639', transport: 'socket'

at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:175)

... 19 common frames omitted

CONFIG

package es.wealth.backoffice.config

import com.mongodb.MongoClient
import com.mongodb.MongoCredential
import com.mongodb.ServerAddress
import es.wealth.backoffice.domain.model.familygroup.FamilyGroup
import es.wealth.backoffice.domain.model.familygroup.FamilyGroupRepository
import es.wealth.backoffice.domain.model.familygroup.event.FamiliyGroupEventHandler
import es.wealth.backoffice.domain.service.FamilyGroupDomainService
import org.axonframework.config.Configurer
import org.axonframework.config.EventHandlingConfiguration
import org.axonframework.eventsourcing.AggregateFactory
import org.axonframework.eventsourcing.EventCountSnapshotTriggerDefinition
import org.axonframework.eventsourcing.EventSourcingRepository
import org.axonframework.eventsourcing.eventstore.EmbeddedEventStore
import org.axonframework.eventsourcing.eventstore.EventStore
import org.axonframework.mongo.eventsourcing.eventstore.DefaultMongoTemplate
import org.axonframework.mongo.eventsourcing.eventstore.MongoEventStorageEngine
import org.axonframework.mongo.eventsourcing.eventstore.MongoTemplate
import org.axonframework.mongo.eventsourcing.eventstore.documentperevent.DocumentPerEventStorageStrategy
import org.axonframework.serialization.json.JacksonSerializer
import org.axonframework.spring.eventsourcing.SpringAggregateSnapshotter
import org.axonframework.spring.eventsourcing.SpringAggregateSnapshotterFactoryBean
import org.axonframework.spring.eventsourcing.SpringPrototypeAggregateFactory
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.context.ApplicationContext
import org.springframework.context.annotation.Bean
import org.springframework.context.annotation.Configuration
import org.springframework.context.annotation.Scope

@Configuration
class AxonConfiguration {

    @Autowired
    FamilyGroupRepository familyGroupRepository
    @Autowired
    FamilyGroupDomainService familyGroupDomainService

    @Bean(name = "axonMongoTemplate")
    MongoTemplate axonMongoTemplate() {
        // TODO config
        MongoClient mongoClient = new MongoClient(new ServerAddress("mongodb", 27017), [MongoCredential.createCredential("wealth-eventstore", "wealth-eventstore", "wealth-eventstore".getChars())])
        MongoTemplate template = new DefaultMongoTemplate(mongoClient,
                "wealth-eventstore", "familyGroup", "familyGroup-snapshot");
        template
    }

    @Bean
    JacksonSerializer jacksonSerializer() {
        new JacksonSerializer()
    }

    @Bean
    EventStore embeddedEventStore() {
        MongoEventStorageEngine storageEngine = new MongoEventStorageEngine(jacksonSerializer(), null, axonMongoTemplate(), new DocumentPerEventStorageStrategy())
        EventStore eventStore = new EmbeddedEventStore(storageEngine)
        eventStore
    }

    @Bean
    SpringAggregateSnapshotterFactoryBean springAggregateSnapshotterFactoryBean() {
        new SpringAggregateSnapshotterFactoryBean()
    }

    @Bean
    @Scope("prototype")
    AggregateFactory<FamilyGroup> transactionAggregateFactory() {
        // TODO generic?
        AggregateFactory<FamilyGroup> aggregateFactory = new SpringPrototypeAggregateFactory<FamilyGroup>()
        aggregateFactory.setPrototypeBeanName("familyGroup")
        aggregateFactory;
    }

    @Bean
    @Scope("prototype")
    FamilyGroup familyGroup() {
        // TODO generic?
        new FamilyGroup(familyGroupRepository, familyGroupDomainService)
    }

    @Bean
    EventSourcingRepository<FamilyGroup> axonFamilyGroupRepository(EventStore eventStore, SpringAggregateSnapshotterFactoryBean springAggregateSnapshotterFactoryBean, ApplicationContext applicationContext) {
        SpringAggregateSnapshotter snapshotter = springAggregateSnapshotterFactoryBean.getObject()
        snapshotter.setApplicationContext(applicationContext)
        EventCountSnapshotTriggerDefinition snapshotTriggerDefinition = new EventCountSnapshotTriggerDefinition(
                snapshotter,
                2);

        new EventSourcingRepository(FamilyGroup, eventStore, snapshotTriggerDefinition)
    }

    @Autowired configure(Configurer configurer,EventHandlingConfiguration ehConfiguration){
        // define an EventHandlingConfiguration

        ehConfiguration.registerEventHandler({conf -> new FamiliyGroupEventHandler()});

        // the module needs to be registered with the Axon Configuration
        configurer.registerModule(ehConfiguration);
    }

    /*
    @Bean
    AggregateAnnotationCommandHandler<FamilyGroup> commandHandler(EventSourcingRepository eventSourcingRepository) {
        new AggregateAnnotationCommandHandler<FamilyGroup>(FamilyGroup, eventSourcingRepository)
    }
    */

}

package es.wealth.backoffice.domain.model.familygroup.event

import groovy.util.logging.Slf4j
import org.axonframework.eventhandling.EventHandler
@Slf4j
class FamiliyGroupEventHandler {

    @EventHandler
    void handle(FamilyGroupCreatedEvent familyGroupCreatedEvent) {
        log.info "onCreate: ${familyGroupCreatedEvent}"
        //familyGroupRepository.create(this)
    }

}

Fernando París

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Jul 14, 2017, 3:28:39 AM7/14/17

to Axon Framework Users

TO enhace some info its important to mention that our aim is to receive events outside the aggregate: we werent able at all with tons of differents configuration

Can you help us to be able to handle events on an non aggregate pojo with axon + springboot?

regards

Allard Buijze

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Jul 15, 2017, 8:28:09 AM7/15/17

to Axon Framework Users

There's a lot of configuration that doesn't make a lot of sense to me. It doesn't need to be wrong, but when having problems like what you're describing, less is more. Classcast exceptions like these typically occur in messy Spring configuration, where a beandefinition overrides another one, which happens to deliver a different type of bean.

Instead of defining a bean of type EventStore, just define the EventStorageEngine. The Axon Spring Boot Starter module will autoconfigure the rest.

If you want to use Event Sourcing, don't specify any repositories. Just annotate your aggregate root class with @Aggregate. Also, don't define the aggregate itself, nor the aggregateFactory as beans. That's all done automatically.

Try to avoid registering event handlers using the eventHandlingConfiguration. If they're Spring @Component annotated and have @EventHandler methods, they are autodiscovered.

Once everything works as expected, you can provide additional configuration for snapshotting.

Cheers,

Allard

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Fernando París

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Jul 17, 2017, 11:24:07 AM7/17/17

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If i do this the following error raises. I cannot hide reactor dependevy. It is used

Added to this if we finally make it work, how can we configure snapshotting? Ive tested to get the eventstore but no bean defined..

g.springframework.context.ApplicationContextException: Failed to start bean 'org.axonframework.spring.config.AxonConfiguration'; nested exception is java.lang.ClassCastException: reactor.bus.EventBus cannot be cast to org.axonframework.eventhandling.EventBus

at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178)

at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:167)