Serde: Support __transaction_state topic

[ver-alex]

Issue submitter TODO list

• I've searched for an already existing issues here
• I'm running a supported version of the application which is listed here and the feature is not present there

Is your proposal related to a problem?

I would like to be able to show content of the Kafka internal topics.

Describe the feature you're interested in

To get a better insight into the internal Kafka transactions topic __transaction_state it would be great to be able to show the key/value in a readable format. The necessary serdes/formatters should be available in the Kafka distribution/clients.

Describe alternatives you've considered

We are currently using the kafka-console-consumer.sh with the formatter for transactions.

$ kafka-console-consumer.sh --formatter "kafka.coordinator.transaction.TransactionLog\$TransactionLogMessageFormatter" --bootstrap-server localhost:29092 --topic __transaction_state --from-beginning

Version you're running

2956664 v1.0.0

Additional context

No response

[github-actions]

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[Haarolean]

I see that __transaction_state messages are not deserialized properly, but __consumer_offsets looks fine to me, can you attach a screenshot?

There's also a __consumer_offsets built-in serde which should be used by default for __consumer_offsets topic:

[kapybro]

Further user feedback is requested. Please reply within 7 days or we might close the issue.

[ver-alex]

Sorry, my bad. __consumer_offsets work as expected. Will amend the initial description.

[kapybro]

Thanks for the additional feedback! We'll get back to your issue soon.