Add resyncPeriod option for drift detection

[eshulman2]

This change introduces a new resyncPeriod field in ManagedOptions that enables periodic reconciliation of resources to detect and correct drift from the desired state in OpenStack.

Motivation: Resources managed by ORC can drift from their desired state due to external modifications in OpenStack. Without drift detection, these changes go unnoticed until the next spec change triggers reconciliation. The resyncPeriod option allows users to configure periodic checks to detect and remediate such drift automatically.

Implementation:

• Add resyncPeriod field to ManagedOptions API
• Add GetResyncPeriod() helper method for safe access with nil handling
• Modify shouldReconcile() in the generic controller to check if enough
  time has passed since the last successful reconciliation
• Schedule next resync when periodic resync is enabled and no other
  reschedule is pending
• Update all CRDs, OpenAPI schema, and documentation

Usage:

spec:
  managedOptions:
    resyncPeriod: 60m  # Reconcile every hour to detect drift

If not specified default sync is 10H. if set to 0, periodic resync is disabled.

Closes: #655

Co-Authored-By: Claude Opus 4.5 [email protected]

[mandre]

That great, it looks relatively straightforward to implement. Some points to consider:

• we'll need docs, and highly visible warnings about the side effects of enabling drift detection (higher loads on the cloud).
• we'll want tests as well
• we probably want the controller to accept a CLI flag, to set a global resync period
• for configuring per Kind resync period (say I want my a force resync of my networks every hour, while more frequent resync of floating IPs), we'll have to think about a solution. Perhaps this solution is KRO.
• we should have a strategy for when the managed resource was updated out-of-band, but ORC does not have the ability to revert it to the expected state (the field is immutable in ORC for example)
• what happens when a managed resource is deleted in OpenStack?
• many more questions

Ideally, we'll discuss all these points in a design document.

[eshulman2]

I'll try to reply some right now:

• we'll need docs, and highly visible warnings about the side effects of enabling drift detection (higher loads on the cloud).

Added a warning in docs

• we'll want tests as well

We need to think how we want to test it but I defiantly agree we should figure out a way to gate it. For now as a draft tested locally on my computer.

• we should have a strategy for when the managed resource was updated out-of-band, but ORC does not have the ability to revert it to the expected state (the field is immutable in ORC for example)

I think in this case it just won't fix the drift but it won't trigger another update I believe as when we are updating we compare the fields that we can change

• what happens when a managed resource is deleted in OpenStack?

This case would behave similarly to reconciling before the resource exist and ORC will try to create it.
EDIT: seems like this is problematic as well

[dlaw4608]

This is nice, I played around with it for a while locally, works great!!

[dlaw4608]

noticed a small typo not from this PR, should be "osResource is not set ...." up to you @eshulman2 if you want to correct it.

[eshulman2]

@mandre I added a second commit to re-create the resource on external delete. I must say I'm a bit uncomfortable with the possible risk profile it might add in edge cases, but I'll leave it here for now for reference and discussion.