The English version of quarkus.io is the official project site. Translated sites are community supported on a best-effort basis.

Dev Services para o Kafka

If any Kafka-related extension is present (e.g. quarkus-messaging-kafka), Dev Services for Kafka automatically starts a Kafka broker in dev mode and when running tests. So, you don’t have to start a broker manually. The application is configured automatically.

Because starting a Kafka broker can be long, Dev Services for Kafka uses Redpanda, a Kafka compatible broker which starts in ~1 second.

Ativar/desativar Dev Services para o Kafka

Os Dev Services para o Kafka é ativado automaticamente, a menos que:

  • quarkus.kafka.devservices.enabled esteja definido como false

  • o kafka.bootstrap.servers esteja configurado

  • todos os canais Kafka de mensagens reativas tenham o atributo bootstrap.servers definido

Dev Services for Kafka relies on Docker to start the broker. If your environment does not support Docker, you will need to start the broker manually, or connect to an already running broker. You can configure the broker address using kafka.bootstrap.servers.

broker compartilhado

Most of the time you need to share the broker between applications. Dev Services for Kafka implements a service discovery mechanism for your multiple Quarkus applications running in dev mode to share a single broker.

O Dev Services para o Kafka inicia o broker com a etiqueta quarkus-dev-service-kafka que é utilizada para identificar o container.

If you need multiple (shared) brokers, you can configure the quarkus.kafka.devservices.service-name attribute and indicate the broker name. It looks for a container with the same value, or starts a new one if none can be found. The default service name is kafka.

Sharing is enabled by default in dev mode, but disabled in test mode. You can disable the sharing with quarkus.kafka.devservices.shared=false.

Definindo a porta

By default, Dev Services for Kafka picks a random port and configures the application. You can set the port by configuring the quarkus.kafka.devservices.port property.

Note que o endereço anunciado do Kafka é automaticamente configurado com a porta escolhida.

Configurando a imagem

Dev Services for Kafka supports Redpanda, kafka-native and Strimzi (in Kraft mode) images.

Redpanda is a Kafka compatible event streaming platform. Because it provides a fast startup times, Dev Services defaults to Redpanda images from redpandadata/redpanda. You can select any version from https://hub.docker.com/r/redpandadata/redpanda.

kafka-native provides images of standard Apache Kafka distribution compiled to native binary using Quarkus and GraalVM. While still being experimental, it provides very fast startup times with small footprint.

O tipo da imagem pode ser configurado utilizando

quarkus.kafka.devservices.provider=kafka-native

Strimzi provides container images and Operators for running Apache Kafka on Kubernetes. While Strimzi is optimized for Kubernetes, the images work perfectly in classic container environments. Strimzi container images run "genuine" Kafka broker on JVM, which is slower to start.

quarkus.kafka.devservices.provider=strimzi

Para o Strimzi, você pode selecionar qualquer imagem com uma versão Kafka que tenha suporte para o Kraft (2.8.1 e superior) em https://quay.io/repository/strimzi-test-container/test-container?tab=tags

quarkus.kafka.devservices.image-name=quay.io/strimzi-test-container/test-container:0.106.0-kafka-3.7.0

Configurando os tópicos no Kafka

You can configure the Dev Services for Kafka to create topics once the broker is started. Topics are created with given number of partitions and 1 replica.

The following example creates a topic named test with 3 partitions, and a second topic named messages with 2 partitions.

quarkus.kafka.devservices.topic-partitions.test=3
quarkus.kafka.devservices.topic-partitions.messages=2

If a topic already exists with the given name, the creation is skipped, without trying to re-partition the existing topic to a different number of partitions.

Você pode configurar o tempo limite para as chamadas do client admin do Kafka utilizadas na criação de tópicos utilizando quarkus.kafka.devservices.topic-partitions-timeout. A predefinição é de 2 segundos.

Suporte aos producers transacionais e idempotentes

By default, the Redpanda broker is configured to enable transactions and idempotence features. You can disable those using:

quarkus.kafka.devservices.redpanda.transaction-enabled=false
As transações Redpanda não suportam um processamento exatamente único.

Conteúdo Relacionado