Circular reference error while trying to add command dispatch intercpetors

mumia · December 4, 2024, 8:38am

Hi.

I have a Kotlin project that uses the Axon Server as the command bus and I’m trying to add command dispatch interceptors to the existing command bus.

This is my config file:

@Configuration
class AxonConfig {
    @Bean
    fun trackingEventProcessorConfiguration(): TrackingEventProcessorConfiguration =
        TrackingEventProcessorConfiguration
            .forSingleThreadedProcessing()
            .andInitialTrackingToken { obj: StreamableMessageSource<TrackedEventMessage<*>?> -> obj.createHeadToken() }

    @Bean
    fun configurer(
        configurer: Configurer,
        addNewTagToNewCategoryCommandInterceptor: AddNewTagToNewCategoryCommandInterceptor,
        addNewTagToExistingCategoryCommandInterceptor: AddNewTagToExistingCategoryCommandInterceptor,
    ): Configurer {
        // Configure event processing
        configurer.eventProcessing { eventProcessingConfigurer ->
            // Enable tracking event processors globally
            eventProcessingConfigurer.usingTrackingEventProcessors()
        }

        // Configure the command bus
        configurer.configureCommandBus { configuration ->
            val commandBusWithInterceptors = configuration.commandBus()

            // Register dispatch interceptors directly on the provided commandBus instance
            commandBusWithInterceptors.registerDispatchInterceptor(addNewTagToNewCategoryCommandInterceptor)
            commandBusWithInterceptors.registerDispatchInterceptor(addNewTagToExistingCategoryCommandInterceptor)

            commandBusWithInterceptors // Return the customized CommandBus
        }

        return configurer
    }
}

But this causes a stack overflow error:

ERROR 35852 --- [walletaccountant] [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'accountAggregateRepository': Failed to instantiate [org.axonframework.modelling.command.Repository]: Factory method 'repository' threw exception with message: null
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:648) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:636) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1355) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1185) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:562) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:522) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:337) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:335) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:975) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:971) ~[spring-context-6.1.14.jar:6.1.14]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:625) ~[spring-context-6.1.14.jar:6.1.14]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:146) ~[spring-boot-3.3.5.jar:3.3.5]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:754) ~[spring-boot-3.3.5.jar:3.3.5]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:456) ~[spring-boot-3.3.5.jar:3.3.5]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:335) ~[spring-boot-3.3.5.jar:3.3.5]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1363) ~[spring-boot-3.3.5.jar:3.3.5]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1352) ~[spring-boot-3.3.5.jar:3.3.5]
	at com.wa.walletaccountant.WalletAccountantApplicationKt.main(WalletAccountantApplication.kt:13) ~[main/:na]
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.axonframework.modelling.command.Repository]: Factory method 'repository' threw exception with message: null
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:178) ~[spring-beans-6.1.14.jar:6.1.14]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:644) ~[spring-beans-6.1.14.jar:6.1.14]
	... 19 common frames omitted
Caused by: java.lang.StackOverflowError: null
	at java.base/java.lang.invoke.DirectMethodHandle.allocateInstance(DirectMethodHandle.java:501) ~[na:na]
	at org.axonframework.config.DefaultConfigurer$ConfigurationImpl.getComponent(DefaultConfigurer.java:1127) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.getComponent(Configuration.java:278) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.commandBus(Configuration.java:128) ~[axon-configuration-4.10.1.jar:4.10.1]
	at com.wa.walletaccountant.common.config.AxonConfig.configurer$lambda$2(AxonConfig.kt:34) ~[main/:na]
	at org.axonframework.config.Component.get(Component.java:85) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.DefaultConfigurer$ConfigurationImpl.getComponent(DefaultConfigurer.java:1132) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.getComponent(Configuration.java:278) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.commandBus(Configuration.java:128) ~[axon-configuration-4.10.1.jar:4.10.1]
	at com.wa.walletaccountant.common.config.AxonConfig.configurer$lambda$2(AxonConfig.kt:34) ~[main/:na]
	at org.axonframework.config.Component.get(Component.java:85) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.DefaultConfigurer$ConfigurationImpl.getComponent(DefaultConfigurer.java:1132) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.getComponent(Configuration.java:278) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.commandBus(Configuration.java:128) ~[axon-configuration-4.10.1.jar:4.10.1]
	at com.wa.walletaccountant.common.config.AxonConfig.configurer$lambda$2(AxonConfig.kt:34) ~[main/:na]
	at org.axonframework.config.Component.get(Component.java:85) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.DefaultConfigurer$ConfigurationImpl.getComponent(DefaultConfigurer.java:1132) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.getComponent(Configuration.java:278) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.commandBus(Configuration.java:128) ~[axon-configuration-4.10.1.jar:4.10.1]
	at com.wa.walletaccountant.common.config.AxonConfig.configurer$lambda$2(AxonConfig.kt:34) ~[main/:na]
	at org.axonframework.config.Component.get(Component.java:85) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.DefaultConfigurer$ConfigurationImpl.getComponent(DefaultConfigurer.java:1132) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.getComponent(Configuration.java:278) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.commandBus(Configuration.java:128) ~[axon-configuration-4.10.1.jar:4.10.1]
	at com.wa.walletaccountant.common.config.AxonConfig.configurer$lambda$2(AxonConfig.kt:34) ~[main/:na]
	at org.axonframework.config.Component.get(Component.java:85) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.DefaultConfigurer$ConfigurationImpl.getComponent(DefaultConfigurer.java:1132) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.getComponent(Configuration.java:278) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.commandBus(Configuration.java:128) ~[axon-configuration-4.10.1.jar:4.10.1]
	at com.wa.walletaccountant.common.config.AxonConfig.configurer$lambda$2(AxonConfig.kt:34) ~[main/:na]
	at org.axonframework.config.Component.get(Component.java:85) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.DefaultConfigurer$ConfigurationImpl.getComponent(DefaultConfigurer.java:1132) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.getComponent(Configuration.java:278) ~[axon-configuration-4.10.1.jar:4.10.1]
	at org.axonframework.config.Configuration.commandBus(Configuration.java:128) ~[axon-configuration-4.10.1.jar:4.10.1]
	at com.wa.walletaccountant.common.config.AxonConfig.configurer$lambda$2(AxonConfig.kt:34) ~[main/:na]

Any ideas?

allardbz · December 4, 2024, 2:25pm

Hi Miguel,

the problem is that you have defined a bean of type Configurer that also has a dependency on a bean typed “Configurer”.
Try defining your bean type as ConfigurerModule. That allows you to remove the dependency on a Configurer bean. The ConfigurerModule is practically a Consumer. Axon will invoke this function at the right time to avoid circular dependencies.

mumia · December 4, 2024, 5:07pm

After some “learning how to do it in Kotlin” time, I tried this:

@Bean
    fun eventProcessingConfigurerModule(): ConfigurerModule =
        ConfigurerModule { configurer: Configurer ->
            configurer.onInitialize { config: org.axonframework.config.Configuration ->
                // Configure event processing
                configurer.eventProcessing { eventProcessingConfigurer ->
                    // Enable tracking event processors globally
                    eventProcessingConfigurer.usingTrackingEventProcessors()
                }
            }
        }

    @Bean
    fun commandBusConfigurerModule(
        addNewTagToNewCategoryCommandInterceptor: AddNewTagToNewCategoryCommandInterceptor,
        addNewTagToExistingCategoryCommandInterceptor: AddNewTagToExistingCategoryCommandInterceptor,
    ): ConfigurerModule =
        ConfigurerModule { configurer: Configurer ->
            configurer.onInitialize { config: org.axonframework.config.Configuration ->
                // Configure the command bus
                configurer.configureCommandBus { configuration ->
                    val commandBusWithInterceptors = configuration.commandBus()

                    // Register dispatch interceptors directly on the provided commandBus instance
                    commandBusWithInterceptors.registerDispatchInterceptor(addNewTagToNewCategoryCommandInterceptor)
                    commandBusWithInterceptors.registerDispatchInterceptor(
                        addNewTagToExistingCategoryCommandInterceptor,
                    )

                    commandBusWithInterceptors // Return the customized CommandBus
                }
            }
        }

But am still getting the same issue, not sure why now.

mumia · December 4, 2024, 5:41pm

Change my implementation to:

@Bean
    fun commandBusConfigurerModule(
        addNewTagToNewCategoryCommandInterceptor: AddNewTagToNewCategoryCommandInterceptor,
        addNewTagToExistingCategoryCommandInterceptor: AddNewTagToExistingCategoryCommandInterceptor,
    ): ConfigurerModule =
        ConfigurerModule { configurer: Configurer ->
            configurer.onInitialize { config: org.axonframework.config.Configuration ->
                // Configure the command bus
                val commandBus = config.commandBus()
                // Register dispatch interceptors directly on the provided commandBus instance
                commandBus.registerDispatchInterceptor(addNewTagToNewCategoryCommandInterceptor)
                commandBus.registerDispatchInterceptor(addNewTagToExistingCategoryCommandInterceptor)
            }
        }

And now I’m getting:

ERROR 65326 --- [walletaccountant] [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

The dependencies of some of the beans in the application context form a cycle:

   accountController defined in file [/Users/mlouromanso/development/WalletAccountant/wallet-accountant/build/classes/kotlin/main/com/wa/walletaccountant/adapter/in/web/AccountController.class]
      ↓
   commandGateway defined in class path resource [org/axonframework/springboot/autoconfig/AxonAutoConfiguration.class]
┌─────┐
|  axonServerCommandBus defined in class path resource [org/axonframework/springboot/autoconfig/AxonServerBusAutoConfiguration.class]
↑     ↓
|  commandBus defined in class path resource [org/axonframework/springboot/autoconfig/AxonAutoConfiguration.class]
↑     ↓
|  springAxonConfiguration
└─────┘


Action:

Relying upon circular references is discouraged and they are prohibited by default. Update your application to remove the dependency cycle between beans. As a last resort, it may be possible to break the cycle automatically by setting spring.main.allow-circular-references to true.

ajisrael · December 4, 2024, 7:11pm

This seems similar to an issue I ran into as well. You can see my “solution” here. It was to add an @Lazy annotation to the classes that depended on the command bus.
Not sure if this applies for Kotlin - sorry , but hopefully this points you in the right direction. I’m not too thrilled with the solution for my implementation, but will hopefully get your app up and running.

mumia · December 4, 2024, 9:57pm

Hey Alex.

Your suggestion, although not pretty, works.

But it seems integration test are also broken, not sure how @Lazy would help there.

Still trying to figure it out.

ajisrael · December 4, 2024, 11:20pm

As you can see on my master branch I’m still auto-wiring the interceptors. Not sure if this will fix your issue with integration tests, and as @Steven_van_Beelen mentioned in the post I previously linked, you’d be running the risk of Spring messing up the ordering. Just thought I’d mention it in case it gets you to a stable spot for now with your tests.

    @Autowired
    public void registerAccountCommandInterceptors(ApplicationContext context, CommandBus commandBus) {
        commandBus.registerDispatchInterceptor(
                context.getBean(ValidateCommandInterceptor.class)
        );
        commandBus.registerDispatchInterceptor(
                context.getBean(AccountCommandsInterceptor.class)
        );
        commandBus.registerDispatchInterceptor(
                context.getBean(BusinessCommandsInterceptor.class)
        );
        commandBus.registerDispatchInterceptor(
                context.getBean(LoyaltyBankCommandsInterceptor.class)
        );
        commandBus.registerDispatchInterceptor(
                context.getBean(TransactionCommandsInterceptor.class)
        );
    }

allardbz · December 5, 2024, 8:07am

If you’re just trying to register interceptors, you should be able to do that like this:

@Autowired
public void registerInterceptors(CommandBus commandBus, MyInterceptor interceptor) {
    commandBus.registerDispatchInterceptor(interceptor);
}

mumia · December 5, 2024, 8:18am

That seemed to do the trick.

My final setup:

import org.axonframework.config.Configurer
import org.axonframework.config.ConfigurerModule
import org.axonframework.eventhandling.TrackedEventMessage
import org.axonframework.eventhandling.TrackingEventProcessorConfiguration
import org.axonframework.messaging.StreamableMessageSource
import org.springframework.context.annotation.Bean
import org.springframework.context.annotation.Configuration

@Configuration
class AxonConfig {
    @Bean
    fun trackingEventProcessorConfiguration(): TrackingEventProcessorConfiguration =
        TrackingEventProcessorConfiguration
            .forSingleThreadedProcessing()
            .andInitialTrackingToken { obj: StreamableMessageSource<TrackedEventMessage<*>?> -> obj.createHeadToken() }

    @Bean
    fun eventProcessingConfigurerModule(): ConfigurerModule =
        ConfigurerModule { configurer: Configurer ->
            // Configure event processing
            configurer.eventProcessing { eventProcessingConfigurer ->
                // Enable tracking event processors globally
                eventProcessingConfigurer.usingTrackingEventProcessors()
            }
        }
}

And

import com.wa.walletaccountant.application.interceptor.command.tagcategory.AddNewTagToExistingCategoryCommandInterceptor
import com.wa.walletaccountant.application.interceptor.command.tagcategory.AddNewTagToNewCategoryCommandInterceptor
import org.axonframework.commandhandling.CommandBus
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.context.annotation.Configuration

@Configuration
class CommandBusConfig {
    @Autowired
    fun registerInterceptors(
        commandBus: CommandBus,
        addNewTagToNewCategoryCommandInterceptor: AddNewTagToNewCategoryCommandInterceptor,
        addNewTagToExistingCategoryCommandInterceptor: AddNewTagToExistingCategoryCommandInterceptor,
    ) {
        commandBus.registerDispatchInterceptor(addNewTagToNewCategoryCommandInterceptor)
        commandBus.registerDispatchInterceptor(addNewTagToExistingCategoryCommandInterceptor)
    }
}

Thank you @allardbz and @ajisrael for the help.

In the process I learned about the ConfigurerModule.