[FLINK-37244] mention scylladb in docs

[mkorolyov]

Hi,

I've implemented examples from the docs for Sinks with and without Pojo classes and for Sources for Apache Cassandra. They were working as expected. Than I just replaced connection string to running ScyllaDB which is a drop-in more performant replacement for Cassandra and checked that all scenarios still working the same so the same connector could be used to integrate Flink with both databases. That why I've updated docs and mentioned ScyllaDB as also supported option.

[boring-cyborg]

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[guy9]

Also interested in this.

[mkorolyov]

going to update the tests to invoke them for 2 containers: Cassandra and ScyllaDB

[mkorolyov]

@dannycranmer Hey, could you pls take a look?

[andrii-kysylevskyi]

Good afternoon! It looks like this PR has been abandoned for some time, but I’d be happy to pick it up and get it over the line.
I’d appreciate any guidance on the best way to proceed. @echauchot, I noticed you’ve been active in this repo - maybe you could advise?
I would plan to create a fork, apply the original author’s changes (keeping them as a co-author), resolve conflicts with main, and open a new PR.

Thanks a lot in advance!

[echauchot]

Good afternoon! It looks like this PR has been abandoned for some time, but I’d be happy to pick it up and get it over the line. I’d appreciate any guidance on the best way to proceed. @echauchot, I noticed you’ve been active in this repo - maybe you could advise? I would plan to create a fork, apply the original author’s changes (keeping them as a co-author), resolve conflicts with main, and open a new PR.

Thanks a lot in advance!

@andrii-kysylevskyi
Yes, you need a fork of the cassandra connector repo, clone it locally, then checkout the PR branch locally for testing (ex for PR 35 on first iteration of review with apache being the remote pointing to the apache repo git fetch apache pull/35/head:pr_35_1 ). Then review it. Once it is approved, a Flink committer can merge. But unfortunately I have no time for reviewing as I'm starting a new job.
As a quick review comment, I'd recommend to add ITests on Scylladb using testConainers Scylladb backend to be able to claim support. I'd hope no change to the prod code is needed and that only a new ITest is enough. Agree on the general idea of using the connector for both DB. Also careful on the doc integration: the connectors docs are integrated from a version branch of the connector to the main Flink doc see doc integraion. I think we could update the doc once the test is passing and with new changes from @Poorvankbhatia and release a v3.3 of the connector and reference v3.3 as described in the doc integration procedure

[andrii-kysylevskyi]

Thank you for the useful information, and hope everything goes smoothly at your new work @echauchot!

Could you recommend someone from the Flink maintainers team I could tag for review in the PR I will submit later? Thanks in advance!

[echauchot]

Thank you for the useful information, and hope everything goes smoothly at your new work @echauchot!

Could you recommend someone from the Flink maintainers team I could tag for review in the PR I will submit later? Thanks in advance!

Thanks !
Among Flink committers, I would recommend either @dannycranmer who did the last release or @zentol who reviewed the first PRs on this repo.

[echauchot]

Agree on the general idea of using the connector for both DB