CLOUDP-235981: Mark certain fields as deprecated for ServerlessSpec

[igor-karpukhin]

All Submissions:

This PR marks the following providerSettings fields as deprecated:

• DiskIOPS

• DiskTypeName

• EncryptEBSVolume

• InstanceSizeName

• VolumeType

• AutoScaling

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• Update docs/release-notes/release-notes.md if your changes should be included in the release notes for the next release.

[github-actions]

https://app.codecov.io/github/mongodb/mongodb-atlas-kubernetes/commit/4eedde7d5ad62647bd7396b27d76f5f5a2e31a51

[josvazg]

My two cents on how we should deprecate this kind of things:

• Step 1: Mark fields deprecated, as this PR does.
• Step 2: Introduce flag to fail validation when deprecated fields are used BUT disabled by default.
• Step 3: Turn on flag by default. Backward compatibility is still possible, but we have given users more than enough time to migrate away from those fields.

Each step is done in a subsequent release and is properly highlighted in the release notes.

WDYT?

[igor-karpukhin]

My two cents on how we should deprecate this kind of things:

• Step 1: Mark fields deprecated, as this PR does.
• Step 2: Introduce flag to fail validation when deprecated fields are used BUT disabled by default.
• Step 3: Turn on flag by default. Backward compatibility is still possible, but we have given users more than enough time to migrate away from those fields.

Each step is done in a subsequent release and is properly highlighted in the release notes.

WDYT?

I'm not sure if we have a deprecation policy written somewhere. I'd say we need to talk to @s-urbaniak when he is back.