kie-kogito-serverless-operator-459: Restructuring of the Cloud -> Operator -> Persistence chapter

[wmedvede]

Closes #608

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[github-actions]

🎊 PR Preview a412e50 has been successfully built and deployed. See the documentation preview: https://sonataflow-docs-preview-pr-628.surge.sh

[wmedvede]

Hi @kaldesai would you mind review this PR?

[nmirasch]

Looks good to me, I've added small suggestions. Feel free to take them into account

[ricardozanini]

oh that's a big one! Many thanks, Walter! Looks really neat. The majority of my comments are style, nitpicks only. Thanks!

[ricardozanini]

Suggested change

	Persistence configurations are applied at workflow deployment time, and potential changes in the SonataFlowPlatform will not impact already deployed workflows.
	Persistence configurations are applied at workflow deployment time, and potential changes in the `SonataFlowPlatform` will not impact already deployed workflows.

is this true? During the platform reconciliation, we do update the persistence configuration. So in case the pod restarts, so it will be the persistence values.

[wmedvede]

Good catch, I didn't know it was expected to work this way, so this is why I added this note as a warning.

So, I did some tests and it looks like it works more or less this way:

I have changed for example the SFP platform persistence, and it looks like the DI, the JS, and the workflow are all restarted. (I mean, not in case the pod restarts, it was forced to restart)

However, we have an issue 😠 with the jobs-service in that case.

The job-service has two database connections:

One connection string, is passed as an env var QUARKUS_DATASOURCE_JDBC_URL in the Deployment.
All good, this connection is updated as part of the restart I commented above.

The second connection string, is passed in the jobs-service-properties config map 😠 , with a property quarkus.datasource.reactive.url. (IDK why it was done this way)

But the config map is not updated as part of the restart procedure. So, the JS restart, is not working well 😠, since the connection passed as env var points to the new database (was refreshed as part of the restart procedure), and the connection passed in the jobs-service-config map points to the old-one (not refreshed as part of the procedure). 😠

While not a blocker, we can't say that this sort of casecade update is working 100% well.

So, I have opened an issue for this situation: apache/incubator-kie-kogito-serverless-operator#468

Alternatives here:

1. we update the documentation saying that this automatic restart/refresh exists, and immediately add a know issue saying that it's not working.

2. we let the documentation as is to not confuse people.

wdyt? @domhanak @ricardozanini

[ricardozanini]

Hey @wmedvede not sure if you know, but if you go to the "review page", you can click on "add to batch" and then commit once :D