bwcPluginMode and extensionDistinguishedNames to ext settings

[samuelcostae]

Description

Draft PR to trigger checks
Added bwcPluginMode and extensionDistinguishedNames settings to extension settings.

Related Issues

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
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• Commit changes are listed out in CHANGELOG.md file (See: Changelog)

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[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: FAILURE ❌
• URL: https://build.ci.opensearch.org/job/gradle-check/17452/
• CommitID: 440b6db
  Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green.
  Is the failure a flaky test unrelated to your change?

[cwperks]

Hi @samuelcostae, it should be possible now to define security settings for extensions from the security plugin by making the security plugin an ExtensionAwarePlugin. These settings can be defined from the security plugin.

This extension point is similar to Plugin.getSettings() which allow plugins to extend the default settings inside opensearch.yml and add settings and define defaults.

See how the security plugin overrides getSettings() to add settings that should be placed in opensearch.yml here: https://github.com/opensearch-project/security/blob/main/src/main/java/org/opensearch/security/OpenSearchSecurityPlugin.java#L898-L1095

[samuelcostae]

Hi @samuelcostae, it should be possible now to define security settings for extensions from the security plugin by making the security plugin an ExtensionAwarePlugin. These settings can be defined from the security plugin.

This extension point is similar to Plugin.getSettings() which allow plugins to extend the default settings inside opensearch.yml and add settings and define defaults.

See how the security plugin overrides getSettings() to add settings that should be placed in opensearch.yml here: https://github.com/opensearch-project/security/blob/main/src/main/java/org/opensearch/security/OpenSearchSecurityPlugin.java#L898-L1095

Thanks @cwperks

So both extensionDistiguishedNames and bwcPluginMode are relevant to the security plugin only, and core's codebase doesn't need to be aware of it , is that correct?

Initially I had started by modifying the SecurityPlugin to read from extensions.yml, but then thought it would be better to define all extension settings in the same place as they seemed generic enough to not be security only, but if that is not the case, makes sense to have these two separate in the SecurityPlugin.

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I have one question about the override getExtensionSettings() Does it automatically have access to all setting files loaded by Core during bootstrap? Or do I need to specify the files similarly to the Dynamic Configs?

[cwperks]

Hi @samuelcostae, ExtensionAwarePlugin.getExtensionSettings() is intended to be used to define settings that should be placed in extensions.yml from a plugin aware of extensions. In this case, I created that extension point in this PR to give the security plugin flexibility to define settings that should be placed in extensions.yml and organized to make it clear that they are settings defined and used for security purposes.

One of the benefits of being able to define and use settings that the security plugin needs from the security plugin is that they would only be defined and utilized in a single repository which decouples core and the security plugin. Since extensions would be released experimental at first, it would allow the security plugin the flexibility to change settings if needed from a single place instead of requiring PRs in multiple repositories.