CLOUDP-338399: External mongod for Search

[anandsyncs]

Summary

This pull request introduces support for using external MongoDB deployments as sources for MongoDBSearch resources, in addition to the previously supported operator-managed deployments. The changes include updates to the CRD API, controller logic, and supporting code to handle configuration, validation, and reconciliation for external sources. Additionally, new end-to-end (e2e) test tasks are added to ensure this functionality is covered.

External MongoDB Source Support

• Added new fields to the MongoDBSource spec (ExternalMongoDBSource and supporting types) to allow specifying external MongoDB deployments, including host/port, credentials, and TLS settings.
• Added logic to distinguish between operator-managed and external sources throughout the controller and resource handling code, including the IsExternalMongoDBSource method and updates to resource reference logic.

Controller and Reconciliation Logic Updates

• Refactored the SearchSourceDBResource interface and its implementations to support both internal and external MongoDB sources, including connection details and version validation.
• Updated reconciliation logic to handle external sources, including skipping version validation and resource watching when not applicable.
• Adjusted service and StatefulSet construction to use new abstraction for host seeds and service accounts.

Testing and CI

• Added new e2e test tasks for external MongoDB source scenarios (e2e_search_external_basic and e2e_search_external_tls) and included them in the appropriate task groups to ensure coverage in CI.
• Updated tests and validation helpers to use the new interface methods and logic.

These changes collectively enable MongoDBSearch resources to work with both operator-managed and external MongoDB deployments, increasing flexibility for users and improving the robustness of the operator.

Proof of Work

Tests pass

Checklist

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  • refer to Changelog files and Release Notes section in CONTRIBUTING.md for more details

[github-actions]

⚠️ (this preview might not be accurate if the PR is not rebased on current master branch)

MCK 1.2.1 Release Notes

Other Changes

• Optional permissions for PersistentVolumeClaim moved to a separate role. When managing the operator with Helm it is possible to disable permissions for PersistentVolumeClaim resources by setting operator.enablePVCResize value to false (true by default). When enabled, previously these permissions were part of the primary operator role. With this change, permissions have a separate role.
• subresourceEnabled Helm value was removed. This setting used to be true by default and made it possible to exclude subresource permissions from the operator role by specifying false as the value. We are removing this configuration option, making the operator roles always have subresource permissions. This setting was introduced as a temporary solution for this OpenShift issue. The issue has since been resolved and the setting is no longer needed.

[fealebenpae]

Looks good! I just recommend explicitly using distinct names for the mdbc and mdbs resources to make sure the implicit name matching isn't kicking in at all.

Please resolve the lint issue and merge.

[lsierant]

I've left some comments

[lsierant]

we should probably make this an utility function as we have few copies of it already

[lsierant]

Do we need that object instead of just a string?

[anandsyncs]

I used this to keep it kind of consistent with rest of the codebase.