How can I expose the Metrics of ActiveMQ Artemis running in embedded mode via Spring Boot 3.x actuators Micrometer metrics API?

Question

How can I configure ActiveMQ Artemis and Spring Boot to expose the metrics of the embedded ActiveMQ Artemis via the actuator API?

My goal is to expose it via the Prometheus endpoint so I can scrape it.

FYI: I am using Spring Boot 3.2

I added the following dependencies

implementation 'org.apache.activemq:artemis-jakarta-server'
implementation 'org.springframework.boot:spring-boot-starter-web'
implementation 'org.springframework.boot:spring-boot-starter-actuator'
implementation 'io.micrometer:micrometer-tracing-bridge-otel'

implementation 'org.springframework.boot:spring-boot-starter-artemis'
runtimeOnly 'io.micrometer:micrometer-registry-prometheus'

My application.properties contains the following settings:

spring.artemis.mode=embedded
spring.artemis.password=test
spring.artemis.user=test
spring.artemis.embedded.enabled=true
spring.artemis.embedded.persistent=true
spring.artemis.embedded.data-directory=./mq-data
spring.artemis.embedded.cluster-password=test
spring.artemis.embedded.topics=module1.out.topic

management.endpoint.health.show-components=always
management.endpoint.health.show-details=always
management.endpoints.web.exposure.include=prometheus,health,hawtio
management.server.port=8090

But still the Prometheus endpoint did not provide the metrics of ActiveMQ Artemis.

Answer 1

I posted the question to answer it myself so that someone else can find the solution faster than I did.

ActiveMQ Artemis provides an interface for a metrics plugin that you can implement. Afterwards you need to configure your embedded ActiveMQ Artemis instance with the plugin.

How did I do it?

1. Provide an Implementation of the ActiveMQMetricsPlugin

   Here is a simple implementation of the class that allows you to pass in the MeterRegistry that Spring Boot Micrometer autoconfiguration provides:

class MicrometerActiveMQMetricsPlugin implements ActiveMQMetricsPlugin {

  private transient MeterRegistry meterRegistry;

  private Map<String, String> options;

  private ActiveMQServer server;

  public MicrometerActiveMQMetricsPlugin(MeterRegistry meterRegistry) {
    if(meterRegistry == null) {
      throw new IllegalArgumentException("Provided meter registry is null.");
    }
    this.meterRegistry = meterRegistry;
  }

  @Override
  public ActiveMQMetricsPlugin init(Map<String, String> options) {
    this.meterRegistry = new SimpleMeterRegistry();
    this.options = options;
    return this;
  }

  @Override
  public MeterRegistry getRegistry() {
    return meterRegistry;
  }

  @Override
  public void registered(ActiveMQServer server) {
    this.server = server;
  }

  public Map<String, String> getOptions() {
    return options;
  }

  public ActiveMQServer getServer() {
    return server;
  }
}

2. Configure ActiveMQ Artemis

   Spring Boot provides an configuration for its auto-configuration that you can use to configure the embedded instance:

@Configuration
@Slf4j
class ArtemisConfigurationCustomizerImpl implements ArtemisConfigurationCustomizer {

  @Autowired private MeterRegistry meterRegistry;
  
  @Override
  public void customize(org.apache.activemq.artemis.core.config.Configuration configuration) {
    log.info("############ CONFIGURING METRICS ############");
    MetricsConfiguration metricsConfiguration = new MetricsConfiguration();
    MicrometerActiveMQMetricsPlugin plugin = new MicrometerActiveMQMetricsPlugin(meterRegistry);

    metricsConfiguration.setPlugin(plugin);
    configuration.setMetricsConfiguration(metricsConfiguration);
  }
}

3. Query the Prometheus endpoint

curl -s localhost:8090/actuator/prometheus | grep -v "#" | grep artemis |sort