kafka-cli-tools

docker image with kafka cli tools

Appreciation and reason for existence

This project owes all of its inspiration and most of the code to: https://github.com/wurstmeister/kafka-docker/

The reason for this repo next to wurstmeister is to allow using different kafka sources (e.g. confluent) and still being able to use topic creation through containers.

Usage example

Caveat: As the CLI tools run inside docker, the container needs to be able to access Kafka from there. This is usually done by spawning the container in the same docker-compose file or by attaching the container to the same docker network Kafka is in.

For a full example see: file in Github

The following examples will be based on this configuration:

# docker-compose.yaml
kafka-cli:
  image: frser/kafka-cli
  environment:
    BOOTSTRAP_SERVER: kafka:9092
    CREATE_TOPICS: >-
      readings:3:1:compact,
      alarms:2:1,
      errors,

Topic creation

This CLI can also create topics via environment configuration. Below are example environment variables to create two topics:

The configuration can be a simple comma separated list CREATE_TOPICS=readings:3:1:compact,alarms:2:1,telemetry.errors.

A neat way to represent it in yaml is with the multi line syntax:

CREATE_TOPICS: >-
  readings:3:1:compact,
  alarms:2:1,
  errors,

# the trailing comma is just for easier copy-pasting

docker-compose run --rm kafka-cli

Waiting for kafka

docker-compose run --rm kafka-cli

Executing a one off command

docker-compose run --rm -e CREATE_TOPICS="" -e START_TIMEOUT=20 kafka-cli kafka-topics.sh --list --bootstrap-server kafka:9092