NIFI-15243 Improve KubernetesConfigMapStateProvider

[bbende]

Summary

NIFI-15243

Improves the KubernetesConfigMapStateProvider....

1. In setState the original code was calling update with a resource that had no resourceVersion specified and under the covers the k8s client will perform a get in this case to obtain the most recent version before performing the update. Given that, we can call get ourselves every time and simplify the logic to know whether to call create or update, plus simplify the conflict handling logic since we can re-call get on each retry.

2. In replace we had no way to preserve any changes made to metadata fields, so getState was updated to return the ObjectMetadata from the ConfigMap inside StandardStateMap, then during replace it can use this metadata when constructing the resource to preserve any values.

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  • JDK 21
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[exceptionfactory]

Thanks for working on these improvements @bbende. The general approach reworking update process for ConfigMaps looks good. I noted a few minor recommendations.

[bbende]

@exceptionfactory thanks for the review, pushed an update to address the comments

[exceptionfactory]

Thanks for making the adjustments @bbende, understanding that the current update() call was already making a GET request, changing the approach to make it explicit, with the accompanying improvements, looks good! +1 merging