Docs: Add compose example using confluent-local docker image

[scprek]

Resolves /discussions/818

• Breaking change? (if so, please describe the impact and migration path for existing application instances)

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• I have performed a self-review of my own code
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[scprek]

I couldn't find a way to "hack" docker compose to treat kafka0 interactions from the other services as localhost (the default env vars in the image). So I ended up just overriding all ENV vars that had localhost in it that were required for Kafka UI and init kafka topics to work.

[Haarolean]

Hi @scprek could you elaborate please, what does this compose add/solve? From your original discussion, it seems that you're interested in a kraft-enabled kafka instance, which is, well, most of the compose examples present in documentation/compose are about.

[scprek]

Hi @scprek could you elaborate please, what does this compose add/solve? From your original discussion, it seems that you're interested in a kraft-enabled kafka instance, which is, well, most of the compose examples present in documentation/compose are about.

Hi yes I can elaborate,

I wanted a way to use image: confluentinc/confluent-local:latest without needing to do any of this stuff since in theory that image is already setup.

      KAFKA_ADVERTISED_LISTENERS: 'PLAINTEXT://kafka0:29092,PLAINTEXT_HOST://localhost:9092'
      KAFKA_CONTROLLER_QUORUM_VOTERS: '1@kafka0:29093'
      KAFKA_LISTENERS: 'PLAINTEXT://kafka0:29092,CONTROLLER://kafka0:29093,PLAINTEXT_HOST://0.0.0.0:9092'
      KAFKA_REST_BOOTSTRAP_SERVERS: 'kafka0:29092'

There's a difference between enabling kraft in a Kafka image and using the Kraft/optimized image confluent-local directly.

See: https://docs.confluent.io/platform/current/installation/docker/image-reference.html#ak-images