How to add Micrometer Timer in KafkaListener class, created by KafkaListenerContainerFactory?

Question

When I try to autowire MicrometerRegistry to a class containing KafkaListener, I get the following error -

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'kafkaConsumer' defined in file [/apps/flux-mariadb-pipeline/build/classes/java/main/com/processor/consumer/KafkaConsumer.class]: Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.processor.consumer.KafkaConsumer]: Constructor threw exception; nested exception is java.lang.NullPointerException
    at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:313)
    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:294)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1358)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1204)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517)
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:893)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:879)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:551)
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:143)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:758)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:750)
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:315)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1237)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226)
    at com.processor.App.main(App.java:10)
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.processor.consumer.KafkaConsumer]: Constructor threw exception; nested exception is java.lang.NullPointerException
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:217)
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:117)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:309)
    ... 20 common frames omitted
Caused by: java.lang.NullPointerException: null
    at java.util.Objects.requireNonNull(Objects.java:203)
    at io.micrometer.core.instrument.ImmutableTag.<init>(ImmutableTag.java:35)
    at io.micrometer.core.instrument.Tag.of(Tag.java:29)
    at io.micrometer.core.instrument.Tags.and(Tags.java:74)
    at io.micrometer.core.instrument.Timer$Builder.tag(Timer.java:364)
    at com.processor.consumer.KafkaConsumer.<init>(KafkaConsumer.java:47)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:204)
    ... 22 common frames omitted

KafkaConsumer class -

public KafkaConsumer(MeterRegistry meterRegistry) {
  eventTimer =
      Timer.builder("travel.time")
          .description("The time it takes for the event to travel.")
          .tag("topic", topic)
          .publishPercentiles(.30, .65, .99)
          .publishPercentileHistogram()
          .minimumExpectedValue(Duration.ofMillis(1))
          .maximumExpectedValue(Duration.ofMillis(5000))
          .register(meterRegistry);
}

@KafkaListener(
    topics = "${spring.kafka.consumer.properties.topic}",
    groupId = "${spring.kafka.consumer.group-id}")
public void consume(
    ConsumerRecord<String, DataRecord> record,
    @Header(KafkaHeaders.RECEIVED_PARTITION_ID) Integer partition,
    @Header(KafkaHeaders.OFFSET) Long offset,
    Acknowledgment ack)
    throws IOException {
  .
  .
  }

I am creating KafkaListener container using the factory as below -

@Bean
  public KafkaListenerContainerFactory<ConcurrentMessageListenerContainer<String, String>>
      kafkaListenerContainerFactory() {

    ConcurrentKafkaListenerContainerFactory<String, String> factory =
        new ConcurrentKafkaListenerContainerFactory<>();

    factory.setConsumerFactory(consumerFactory());
    factory.setConcurrency(8);
    factory.getContainerProperties().setAckMode(AckMode.MANUAL_IMMEDIATE);
    factory.setErrorHandler(getErrorHandler());

    return factory;
  }

Only way I found to add micrometer registry is like below

@Bean public ConsumerFactory<String, String> consumerFactory() {
    Map<String, Object> props = kafkaProperties.buildConsumerProperties();

    DefaultKafkaConsumerFactory<String, String> cf = new DefaultKafkaConsumerFactory<>(props);

    cf.addListener(new MicrometerConsumerListener<>(meterRegistry(),
        Collections.singletonList(new ImmutableTag("customTag", "customTagValue"))));

    return cf;
  }

Now, I do not know how to access this registry inside the @KafkaListener method

Answer 1

at io.micrometer.core.instrument.ImmutableTag.(ImmutableTag.java:35)

.tag("topic", topic)

The topic variable is null.

If it has a @Value annotation, you can't use it in the constructor; create the meter in an @PostConstruct method instead.