Configuring This Extension

Chances are high that you will be using Spring Boot if you are also using Spring Cloud. As configuring goes, this would opt for usage of the axon-springcloud-spring-boot-starter dependency to automatically retrieve all required beans. In either case, your application should be marked to enable it as a discoverable service through Spring Cloud. This can, for example, be done by annotating the main class with @EnableDiscoveryClient.

There are still quite a few customizable components. For some suggestions, take a look at the following examples:

Custom Bean Configuration
Spring Boot AutoConfiguration

// Custom Spring Boot app, enabling a 'DiscoveryClient' and 'Registration' through `@EnableDiscoveryClient`
@EnableDiscoveryClient
@SpringBootApplication
public class MyApplication {

    public static void main(String[] args) {
        SpringApplication.run(MyApplication.class, args);
    }

    @Bean
    public CapabilityDiscoveryMode capabilityDiscoveryMode(RestTemplate restTemplate, Serializer serializer) {
        return RestCapabilityDiscoveryMode.builder()
                                          .restTemplate(restTemplate)
                                          .serializer(serializer)
                                          // Allows changing the endpoint used to find member capabilities
                                          .messageCapabilitiesEndpoint(/* custom message information endpoint */)
                                          .build();
    }

    @Bean
    public CommandRouter springCloudCommandRouter(DiscoveryClient discoveryClient,
                                                  Registration localServiceInstance,
                                                  CapabilityDiscoveryMode capabilityDiscoveryMode) {
        return SpringCloudCommandRouter.builder()
                                       .discoveryClient(discoveryClient)
                                       .routingStrategy(new AnnotationRoutingStrategy())
                                       .localServiceInstance(localServiceInstance)
                                       .capabilityDiscoveryMode(capabilityDiscoveryMode)
                                       .serviceInstanceFilter(/* custom ServiceInstance filter */)
                                       .consistentHashChangeListener(/* ConsistentHash change listener */)
                                       .build();
    }

    // Only required if Axon Spring Boot Starter is not used
    @Bean
    @Qualifier("localSegment")
    public CommandBus localSegment() {
        return SimpleCommandBus.builder().build();
    }

    @Bean
    public CommandBusConnector springHttpCommandBusConnector(@Qualifier("localSegment") CommandBus localSegment,
                                                             RestOperations restOperations,
                                                             Serializer serializer) {
        return SpringHttpCommandBusConnector.builder()
                                            .localCommandBus(localSegment)
                                            .restOperations(restOperations)
                                            .serializer(serializer)
                                            .executor(/* custom Executor */)
                                            .build();
    }

    @Bean
    @Primary
    public DistributedCommandBus distributedCommandBus(CommandRouter commandRouter,
                                                       CommandBusConnector commandBusConnector) {
        return DistributedCommandBus.builder()
                                    .commandRouter(commandRouter)
                                    .connector(commandBusConnector)
                                    .build();
    }
}

# Required to enabled the DistributedCommandBus
axon.distributed.enabled=true
# Defines the load factor used for this segment. Defaults to 100
axon.distributed.load-factor=100
# Defines the CapabilityDiscoveryMode used. Defaults to REST
axon.distributed.spring-cloud.mode=rest
# Defines the endpoint used to retrieve member capabilities from. Defaults to "/member-capabilities"
axon.distributed.spring-cloud.rest-mode-url="/my-custom-endpoint"
# Defines whether the CapabilityDiscoveryMode should be decorated to ignore faulty ServiceInstances
axon.distributed.spring-cloud.enable-ignore-listing=true
# Defines whether the CapabilityDiscoveryMode should be decorated to accept all types of commands
axon.distributed.spring-cloud.enable-accept-all-commands=true