How to manage related applications

Relations to new applications are supported via the “kafka_client” interface.

Within juju via kafka_client interface

If the charms supports the kafka_client interface, just create a relation between the two charms:

juju relate kafka application

To remove a relation:

juju remove-relation kafka application

Outside juju or for charms not implementing kafka_client

The kafka_client interface is used with the data-integrator charm. This charm allows to automatically create and manage product credentials needed to authenticate with different kinds of data platform charmed products:

Deploy the data-integrator charm with the desired topic-name and user roles:

juju deploy data-integrator --channel edge
juju config data-integrator topic-name=test-topic extra-user-roles=producer,consumer

Relate the two applications with:

juju relate data-integrator kafka

To retrieve information, enter:

juju run-action data-integrator/leader get-credentials --wait

This should output something like:

unit-data-integrator-0:
  UnitId: data-integrator/0
  id: "4"
  results:
    kafka:
      consumer-group-prefix: relation-27-
      endpoints: 10.123.8.133:19092
      password: ejMp4SblzxkMCF0yUXjaspneflXqcyXK
      tls: disabled
      username: relation-27
      zookeeper-uris: 10.123.8.154:2181,10.123.8.181:2181,10.123.8.61:2181/kafka
    ok: "True"
  status: completed
  timing:
    completed: 2023-01-27 14:22:51 +0000 UTC
    enqueued: 2023-01-27 14:22:50 +0000 UTC
    started: 2023-01-27 14:22:51 +0000 UTC

Internal Password rotation

The operator user is used internally by the Charmed Kafka Operator, the set-password action can be used to rotate its password.

# to set a specific password for the operator user
juju run-action kafka/leader set-password password=<password> --wait

# to randomly generate a password for the operator user
juju run-action kafka/leader set-password --wait