Major Releases

Persistent streams #3030

Inject multiple test resources #2948

Persistent stream configuration #3043

Rebalance Segments in PooledStreamingEventProcessor #3028

[#3007] Set a SmartLifecycle phase lower than the ones written in the spring WebServer lifecycle ones. #3009

Spring: Place the Axon shutdown hook AFTER the WebServer ones #3007

Update index.adoc, remove link to how-to’s #2978

Automate migration to Axon 4.9+ #2944

refactor: Parameterized logging with constant log values #2910

Enhancement/test container reuse #2883

Removed old from AF reference guide docs module #3046

Updated links to Extensions and appendices #3041

Changed broken xref to broken links - to allow the build process to f… #3032

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Add suppressible log message when console client is not on the classpath. #2868

Instruct compiler to include parameter names metadata #2835

Log notification about AxonIQ console, if console-framework-client is not there #2819

Add additional Axon Server connector configuration to the AxonServerConfiguration #2815

Introduce the AxonServerEventStoreFactory #2807

Claim segments operation for Streaming Event Processors #2803

Add property to easily disable using Axon Server as event store. #2801

Add support for Spring Docker Compose #2790

Add CBOR format and Spring Boot properties for support #2777

Allow easy configuration of CBOR #2776

Support Java modules #2427

Add JDK21 to GitHub Actions #2866

[#2843] Make it possible to have multiple instances of the DbScheduler components. #2853

AxonDbSchedulerAutoConfiguration can not be used multiple times in hierarchical Spring context due to static fields #2843

Add intermediate span factories for Event Processors #2834

Add intermediate span factories for Sagas and Repositories #2830

Add intermediate span factories for DeadlineManager #2829

Intermediate Span Factory pattern for buses #2826

Intermediate Span Factory pattern for snapshotters #2824

Dead-Letter Sequence Identifier Caching #2818

Detect empty snapshots due to Serializer misconfiguration #2817

Improve Event Scheduler context configuration #2810

Implement StreamingEventProcessor.claimSegment #2805

Improve Spanfactory configurability #2780

Default to ReplayToken upon creation of new event processor #2778

Prevent processors from resetting when no handlers support replay #2769

Improve JavaDoc of the CommandTargetResolver #2742

Execute the axon-spring-boot-3-integrationtests actually with spring 3 #2862

Resolve classloading issue with ConnectionDetails #2833

Fix some typos #2783

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[#2689] Support Snapshotting for Polymorphic Aggregates #2753

Allow property based configuration of load balancing strategies #2750

Add test-summary step #2745

[#1828] Add Anchore Container Scan step #2744

[#2350] JDBC Dead-Letter Queue #2743

Enable tracing in DistributedCommandBus with SpanFactory #2729

Make the token store claim timeout easily configurable. #2722

Allow easy (property) configuration for the claimTimeout of the default TokenStore #2708

Introduce Polymorphic Aggregate Snapshotting auto-configuration #2689

[#2639] Handler Interceptor support for Dead Letter Processing #2661

[#2640] Support @ExceptionHandler and @MessageHandlerInterceptor annotated methods in Sagas #2656

Support @ExceptionHandler annotated methods in Sagas #2640

Handler Interceptor support for Dead Letter Processing #2639

Add an auto-merge step for Dependabot Pull Request #2608

2581 Allow to override EventSchema without modifying default JdbcEve… #2582

Allow to override EventSchema without modifying default JdbcEventStorageEngine in Spring context #2581

Allow Development mode on test containers #2461

Autoconfigure automatic load balancing #2453

Enable tracing in DistributedCommandBus with SpanFactory #2403

JDBC Dead-Letter Queue #2350

Validate test-summary GitHub Action #2228

Investigate usage of the Anchore Container Scan in GitHub Actions #1828

Introduce AxonServerContainer as test-container #2763

[#2755] Align assertion messages #2757

Put test assertion errors on multiple lines #2755

Add db-scheduler implementation of the Event Scheduler and Deadline Manager #2727

Add db-scheduler implementation of the Event Scheduler and Deadline Manager #2724

Add JCacheAdapter test scenarios #2721

Make Configuration accessible #2700

refactor: Spring Boot 2.x best practices #2663

Improve error message in case a streaming query gives an error. #2662

Error handling of Streaming queries is less than ideal #2660

Add a warning to the creation of the in memory token store. #2650

Add a registerDeadLetterQueueProvider method in the EventProcessingConfigurer. #2633

[#2628] Extended support for Spring application context hierarchy #2629

ObjectMapper cannot be resolved from Spring Parent Context #2628

Move AbstractDeadlineManagerTestSuite to spring module so it’s deployed. #2622

Clean the test logs #2606

Create a SequencedDeadLetterQueueFactory #2598

2581 Do not duplicate bean definition of TokenStore #2587

[#2074] Allow to customize saga schema table and columns #2575

Auto-merge successful Dependabot Pull requests #2569

Move to use job builder to have more control how the jobs are stored. Add auto configuration. #2564

Enable cancelAll and cancelAllwithinScope in the JobRunrDeadlineManager. #2507

Add JCacheAdapter test scenarios #2421

Change jdbc column names to snake case as default. #2074

Add cache using EhCache 3 #2709

Add cache using Ehcache 3 #2420

Remove payloadType tag from EventProcessorLatencyMetric #2683

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[#1509] Add whenConstructing and whenInvoking to the AggregateTestFixture #2551

[#2476] Support EventMessage handler interceptor registration on the SagaTestFixture #2548

[#2351] The DeadLetter Parameter Resolver #2547

Add Configurer#registerHandlerEnhancerDefinition #2545

[#1123] Support Repository bean wiring through generics #2527

Implement the JobRunr implementation of the event scheduler. #2509

JobRunr DeadlineManager #2499

Added parameter resolver for aggregate type retrieval from domain event messages #2498

Implement Event Handler Interceptors registration on SagaTestFixtures #2476

Message Handler (parameter) support for Dead Letters #2351

Alternative deadline manager: JobRunr (Quartz alternative) #2192

Allow the AggregateTestFixture to expect methods to be called instead of commands passed. #1509

Allow replay on a Saga #1458

Provide alternatives for QuartzEventScheduler and QuartzDeadlineManager #1106

Configurable Locking Scheme in SagaStore #947

Fixed SpringAggregateLookup initialization issue for Spring AOT #2578

[#2561] Move Sonar to JDK17 #2574

Automatically approve Dependabot[bot] PRs #2566

Add Segment and Token to UnitOfWork of PooledStreamingEventProcessor #2562

Move Sonar to JDK17 build #2561

[#2129] Fine tune Repository registration in the AggregateTestFixture #2552

[#1630] Allow disabling of sequence number generation in the GenericJpaRepository #2550

Several fixes to successfully run a JDK17 build #2544

Adjust Dependabot behavior #2536

Enable heartbeats to Axon Server by default #2530

[#2383] Add ConditionalOnMissingBean to SpringAxonConfiguration and SpringConfigurer #2526

Small test and code improvement for JobRunr deadline manager #2510

Introduce the NestingSpanFactory #2487

Improve mismatch messages for Hamcrest Matchers #2400 #2418

Allow OpenTelemetrySpanFactory to only create child spans #2404

Add ConditionalOnBean to InfraConfiguration Beans #2383

AggregateTestFixture creates EventSourcingRepository and does not invalidate it #2129

JDK16 - axon-messaging own unit test fail on #1826

GenericJpaRepository to enable/disable the sequence number generation #1630

Fix typos in Javadoc #2475

Aggregate Repository Spring wiring causes NullPointerException #1123

Asserting checked exception while creating an Aggregate #782

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Added Slack release announcement #2348

[#2307] Carry the context during reset to the ReplayToken #2312

Propagate ResetContext in ReplayToken #2307

[#2198] Add support for Jakarta #2301

Native Tracing for Axon Framework with OpenTelemetry as default #2294

[#2021] Dead Letter Queue for Event Processing Groups #2258

JPA dead letter queue implementation #2239

Construct means to switch between classes using javax and jakarta #2198

Create add-dependabot-pr-to-project.yml #2183

Create add-issues-to-project.yml #2182

Multiteant support #2156

Spring event for indication that Axon has started #2146

Application events when handlers are registered #2144

[#1125] Introduce SagaLifecycle.associationValues() #2141

[#1964] Include AxonServerHealthIndicator #2130

AggregateTestFixture improvement - Validate Exception Details #2125

AggregateTestFixture improvement - Validate Exception Details #2110

Feature/1466 Additional deadline validation methods #2071

Multi-tenant support #2045

Dead-Letter Queue for Event Processors #2021

Added AxonServerEEContainer and AxonServerSEContainer as an easier way for people to write tests #2020

Streaming query #2001

[#1967] Fetch available segements only from the TokenStore #1997

[#1645] Introduce ObjectNode-to/from-JsonNode ContentTypeConverter for the JacksonSerializer #1995

[#1490] Simplify LockFactory configuration for Aggregates #1992

[#1986 Introduce EventProcessingConfigurer#defaultTransactionManager method #1989

Register default Transaction Manager through Event Processing Configurer #1986

Add method returning the available segments of a TokenStore #1967

Add an actuator health indicator to check the connection between the application and Axon Server #1964

Added the MetaDataSequencingPolicy #1930

Provide a SequencingPolicy based on a MetaData field #1929

Added an option to create a fixture for a state stored aggregate #1772

JsonNode-to-ObjectNode ContentTypeConverter #1645

Simplify LockFactory configuration per aggregate #1490

Additional Deadline Validation methods. #1466

Allow TrackingEventProcessor start to be deferred #1184

Accessing Saga Association Values #1125

Signal when all Handlers have been registered in Spring environment #880

Improve deadline span name. #2360

Make Given-phase Error Handling configurable for Saga Test Fixtures #2356

Improve SpanFactory autoconfiguration mechanism. #2354

Introduce LoggingSpanFactory and MultiSpanFactory #2353

Check if a certain handler contains certain methods before registering it. #2346

Catch exceptions from correlation data providers. #2345

Throw exception on ambiguous dependencies #2344

Integration Test for Command and Query Priority Calculations #2342

Include message identifier in error message if de-serialization fails #2330

Add CorrelationDataProvider error handling on rollback #2328

Strip test prefix once required in JUnit 3 from test method names #2321

Apache Maven Wrapper 3.8.6 #2320

Allow ReplayToken creation to be customizable when resetting a projection #2308

Ensure all dispatchable messages are serialiable by Jackson and XStream. #2295

Testclasses for javax jakarta extension #2280

Remove redundant method definition #2270

Integration Test for Command and Query Priority Calculations #2266

Update the PrioritizedRunnable to a PriorityTask #2265

Automatically add Release Notes on milestone closure to Discuss post #2264

Create a protected method to fetch tracking events on JpaEventStorageEngine #2262

Create a protected method to fetch tracking events on JpaEventStorageEngine. #2259

Allow subtype definition on the Repository builders for Polymorphic Aggregates #2250

Add test for ConsistentHash.equals #2244

Use getHost instead of getContainerIpAddress #2222

Default snapshotfilter with revision null #2213

Default snapshot filter with revision null #2212

Creation policy factory for Aggregates #2209

Removed deprecated code by updating the default serializer initialization #2206

Flux response type rank matching #2197

Introduce conditional variants for ApplyMore #2174

Conditional variant for the ApplyMore methods #2173

Take into account the result of the equals method before attempting… #2171

Improve javadoc of the ReplayStatus enum to reflect changes to the StreamingEventProcessors #2170

MultipleInstancesResponseType should match (lower) on single item #2148

Add duplicate resolution on query handler registration, defaulting to… #2140

Add method on DefaultCommandGateway to be able to customize callbacks #2139

Default Revision SnapshotFilter in absence of annotation #2136

Fine tune the MessageHandlerLookup for Spring Native support #2106

Redesign of Spring Boot Auto Configuration support #2105

Feature/1629 saga test fixture #2101

[#2093] Validate if target Command Handling Member can resolve target #2095

Allow several Aggregate Member collections of the same type #2093

Changed logging about "processor falling behind" #2073

Make asDomainEventMessage available to subclasses #2066

Make JpaEventStorageEngine#asDomainEventMessage(EventMessage<?>) protected #2065

Separate Integration Tests and Aggregate coverage reports #2063

[#1646] Update "No Handler For" exceptional cases #2062

[#1711] Simplify attachment of Lifecycle Operations #2061

Change how Sonar is invoked for GHA’s #2033

Introduce LifecycleAware interface for managing component lifecycle #2028

Remove MonoWrapper usage. #2008

Replaced method.getParametersTypes().length by method.getParameterCount()) #1987

Methods for testing deadlines when time passed are consistent in TestExecutor & SagaTestFixture (fixes #1974) #1975

Make methods for testing Deadlines consistent for TestExecutor and SagaTestFixture #1974

Added jdk17-ea on our build workflow for early feedback #1915

Add configurable options for checking failure transiency #1910

Prevent stack trace generation for HandlerExecutionException #1905

Allow creation of HandlerExecutionExceptions without stacktrace #1901

[#1898] Empty associationProperty leads to IndexOutOfBoundsException #1899

Empty associationProperty leads to IndexOutOfBoundsException #1898

Provide means of configuring a CommandCallback #1889

Splitted builds into pr and not pr, added ghactions to Dependabot and other minors #1830

Fine tune triggered Deadline validation for Test Fixtures #1797

Simplified DeadlineManager configuration #1796

Expand RetryScheduler to support more granular decision when to retry #1723

Simplify attachment of Lifecycle Operations #1711

Improved termination heuristic when response is < batchsize/2 and the… #1691

Exception in startHandlers is "swallowed" by exception in shutdownHandlers #1669

Fine tune "No Handler For…" Exception #1646

SagaTestFixture should support expectSuccessfulHandlerExecution() #1629

Large number of rolled back transactions on JPA/JDBC TokenStore #1475

Reduce Reflection usage #1427

Add annotation NonNull/Nullable for better usage in Kotlin (also java) #1280

Spurious warnings when a tracking token gap appears then is filled #1193

Query handlers of the same name and response type within one class #719

MultipleInstancesResponseType should recognize handler with single result #602

Rename SpanFactory.registerTagProvider to registerSpanAttributeProvider #2347

[#2341] Adjust type checking in SimpleQueryUpdateEmitter to accompany type erasure #2343

UpdateEmitter drops MultipleInstancesResponseType updates due to type checking. #2341

Parameter resolver ordering is wrong for test fixtures #2340

Take all types into account when resolving the deadline handler #2336

When moving to a polymorphic Aggregate the stored Deadlines are not handled. #2333

[#2331] Fix deserialization bug GrpcBackedSubscriptionQueryMessage and filter non-handler-matching updates #2332

GrpcBackedSubscriptionQueryMessage overwrites update type with initial response type #2331

[#2317] Using deadlines with DefaultConfigurer leads to NPE #2319

Using deadlines with DefaultConfigurer leads to NPE #2317

Fix streaming queries not respecting PriorityTask mechanism #2309

[#2268] Adjust ConditionalOnClass to validate existence of the AxonServerConnectionManager in absence of the axon-server-connector package. #2269

Bug when using Spring actuator starter and excluding axon server #2268

Support Cache and LockFactory configuration on @Aggregate stereotype #2254

Extracted lambdas to inner static classes #2240

Dependency on reactor is needed to be able to start an Axon app using current 4.6.0-SNAPSHOT #2238

Fix snapshots not being deployed to nexus #2237

fix javadoc: default port is 8124, not 8123 #2223

fix typo in local variable name #2218

Publisher Response Type #2215

EventProcessingModule should lazily initialize processors #2180

Fix StreamingEventProcessor#maxCapacity for the TrackingEventProcessor #2124

Restore missing commit 6e531a6cf173243adf9519905f42cbec0a334238 #2116

Wire eventSerializer into QuartzEventSchedulerFactoryBean #2115

Wire the event Serializer into QuartzEventSchedulerFactoryBean #2088

Fix typo in pom.xml #2022

Fix typos #2016

Exponential Retry for Tracking event processor not happening for transient exceptions when using Postgres JdbcTokenStore #1920

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A new type of EventProcessor has been introduced in pull request #1712, called the PooledStreamingEventProcessor. This EventProcessor allows the same set of operations as the TrackingEventProcessor, but uses a different threading approach for handling events and processing operations. In all, this solution provides a more straightforward processor implementation and configuration, allowing for enhanced event processing in general. For specifics on how to configure it, check out this section.

Sagas support the use of Deadline Handlers, but an @DeadlineHandler annotated method couldn’t automatically close a Saga with the @EndSaga annotation. This enhancement has been described in #1469 and resolved in pull request #1656. As such, as of Axon 4.5, an @DeadlineHandler annotated can also be annotated with @EndSaga, to automatically close the Saga whenever the given deadline is handled.

Whenever an application uses snapshots, the point arises that old snapshot versions need to be invalidated when loading an Aggregate. To that end the SnapshotFilter can be configured. As a simplified solution, the @Revision annotation can now be placed on the Aggregate class to automatically configure a revision based SnapshotFilter. Due to this, old snapshots will be filtered out automatically when an Aggregate is reconstructed from the EventStore. For those interested, the implementation of this feature can be found here.

At the basis of Axon’s message handling functionality, is the MessageHandlingMember. For the time being, the sole implementation of this is the AnnotatedMessageHandlingMember, which expect the use of annotations like the @CommandHandler and @EventHandler, for example. As a step towards constructing an annotation-less approach, #1621 was introduced into the framework. The first steps taken in this pull request are the deprecation of annotation-specific methods from the MessageHandlingMember interface. Added to this is a new approach towards defining attributes of a message handling member through HandlerAttributes.

The InMemoryEventStorageEngine is a good fit for testing purposes. However, it included a discrepancy towards the event storing solution compared to other event storage solutions. This issue was addressed in #1056 and resolved in pull request #1660.

In issue #1733 a confusion around the EventUtils#asDomainEventMessage was described. This reiterated the fact that this method is purely intended for internal use inside Axon Framework, which was not clear to the users. As such, it has now been deprecated, containing a clear statement why this method is not to be used.

Axon Framework can now be used in conjunction with Spring Boot Developer Tools. You can simply achieve this by adding the required dev-tools dependency to your project.

As a partial solution to #1106, Axon Server can now be used to schedule events. Building an AxonServerEventScheduler as the EventScheduler implementation as defined through the builder is sufficient to start with scheduling events through Axon Server.

An EventTrackerStatusChangeListener can now be configured for a TrackingEventProcessor, as was requested in #1338. It can be configured through the TrackingEventProcessorConfiguration, allowing users to react upon status changes of each thread processing event messages.

Component specific message handler interceptors can now be defined through a dedicated annotation: the @MessageHandlerInterceptor annotation. This annotation allows you to introduce a specific bit of logic to be invoked prior to entering the message handling function or after invocation. It for example allows the additional introduction of a @ExceptionHandler annotation, allowing you to specifically deal with the exceptions thrown from your message handlers. The original pull request can be found under #1394. For more specifics on using this annotation, check out the @MessageHandlerInterceptor section.

Configuring a Snapshotter and SnapshotFilter have been simplified in this release. Pull request #1447 shares the load of allowing for distinct Snapshotter configuration. Issue #1391 describes the intent to the configuration of snapshot filtering to be performed on Aggregate level. The former can be configured through the Configurer, whereas the latter is by usage of the AggregateConfigurer.

The AggregateTestFixture was incorrectly noting an old method in one of its exceptions. This has been marked and resolved in #1428.

The CommandValidator and EventValidator had a minor discrepancy; namely, the CommandValidator cleared out contained commands upon starting whereas the EventValidator didn’t. Pull request #1438 resolved the problem at hand.

Aggregate Polymorphism has been introduced, allowing for an aggregate hierarchy to come naturally from a domain model. To set this up, the AggregateConfigurer#withSubtypes(Class…​ aggregates) method can be used. In a Spring environment, an aggregate class hierarchy will be detected automatically. For more details on this feature, read up on it here.

An Axon application will now shutdown more gracefully than it did in the previous releases. This is achieved by marking specific methods in Axon’s infrastructure components as a @StartHandler or @ShutdownHandler. A 'phase' is required in those, specifying when the method should be executed. If you want to add your own lifecycle handlers, you can either register a component with the aforementioned annotations or register the methods directly through Configurer#onInitialize, Configuration#onStart and Configuration#onShutdown.

We have introduced the @CreationPolicy annotation which you can add to @CommandHandler annotated methods in your aggregate. Through this, it is possible to define if such a command handler should 'never', 'always' or 'create' an aggregate 'if-missing'. For further explanation read the Aggregate Command Handler Creation Policy section.

Both the XStreamSerializer and JacksonSerializer provide a means to toggle on "lenient serialization" through their builders.

Various test fixture improvements have been made, such as options to register a HandlerEnhancerDefinition, a ParameterResolverFactory and a ListenerInvocationErrorHandler. Additional validations have been added too, revolving around asserting scheduled events and deadline message. The Test Fixture page has been updated to define these new operations accordingly.

The TrackingEventProcessor#processingStatus method as of 4.3 exposes more status information. The current token position, token-at-reset, is-merging and merge-completed position have been added to the set. Read the Event Tracker Status section for more specifics on this.

A ConcurrencyException was thrown when an aggregate was created at two distinct JVM’s at the same time. As ConcurrencyException`s are typically retryable, the creation command would be issued again if a `RetryScheduler was in place. Retrying this operation is however useless and hence has been replaced for an AggregateStreamCreationException in pull request #1333.

The test fixtures for state-stored aggregates did unintentionally not allow resource injection. This problem has been resolved in pull request #1315.

The MultiStreamableMessageSource did not deal well with one or several exceptional streams. Hence exception handling has been improved on this matter in #1325.

Axon Framework applications can now use tags to support a level of 'location awareness' between Axon clients and Axon Server instances. This feature is further described here.

Axon Server already supported several contexts, but Axon Framework application could not specify to which context message should be dispatched. The Axon Server Connector has been expanded with a TargetContextResolver to allow just this.

A new implementation of the StreamablbeMessageSource has been implemented: the MultiStreamableMessageSource. This implementation allows pairing several "streamable" message sources into a single source. This can in turn be used to for example read events from several distinct contexts for a single Tracking Event Processor.

Handler Execution Exception now allow application specific information to be sent back over the wire in case of a distributed set up.

The TrackingToken interface now provides an estimate of it’s relative position in the event stream through the position() method.

Optional return types can now be used for Query Handling methods.

An Aggregate’s Snapshotter was not auto configured when Spring Boot is being used, as was filed under #932.

The CommandResultMessage was returned as null when using the DisruptorCommandBus. This was solved in pull request #1169.

The ScopeDescriptor used by the DeadlineManager had serialization issue when a user would migrate from an Axon 3.x application to Axon 4.x. The axon-legacy package has been expanded to contain legacy `ScopeDescriptor`s to resolve this problem.

The TrackingEventProcessor now has an API to split and merge TrackingTokens during runtime of an application. Axon Server has additions to the UI to split and merge a given Tracking Event Processor’s tokens.

Next to Dropwizard metrics the framework now also supports Micrometer metrics. The MessageMonitor interface is used to allow integration with Micrometer. Lastly, we are incredibly thankful that this has been introduced as a community contribution.

Primitive types are now supported as @QueryHandler return types.

We have introduced the EventGateway in a similar fashion as the CommandGateway and QueryGateway. As with the command and query version, the EventGateway provides a simpler API when it comes to dispatching Events on the EventBus.

Command and Query message priority was not set correctly for the Axon Server Connector. This issue has been addressed under bug #1004.

The CapacityMonitor was not registered correctly for Event Processor, which user "Sabartius" resolved under issue #961.

Some exception were not reported correctly and/or clearly when utilizing the Axon Server Connector (issue marked under number #945).

The package structure of Axon Framework has changed drastically with the aim to provide users the option to pick and choose. For example, if only the messaging components of framework are required, one can directly depend on the axon-messaging package.

In part with the package restructure, all components which leverage another framework to provide something extra have been given their own repository. These repositories are called the Axon Framework Extensions.

The configuration of Event Processor has been replaced and greatly fine tuned with the addition of the EventProcessingConfigurer.

Some new defaults have been introduced in release 4.0, like a bias towards expecting a connection with Axon Server. Another important chance is the switch from defaulting to Tracking Processors instead of Subscribing Processors.

The notion of a CommandResultMessage has been introduced as a dedicated message towards the result of command handling.

To simplify configuration and more easily overcome deprecation, the Builder pattern has been implemented for all infrastructure components.