[FEATURE]: Delete annotations from objects after they are deleted from the namespace

[shanduur]

Is your feature request related to a problem? Please describe.

Currently, when annotations are removed from the namespace, they remain on the previously annotated objects (e.g., Deployments, Services) unless manually removed. This can lead to outdated or incorrect annotations persisting on resources, which might cause confusion or unwanted behavior.

Describe the solution you'd like.

I would like Scribe to automatically remove annotations from resources when they are deleted from the namespace's annotations. This would ensure that resources stay in sync with the current state of the namespace's annotations.

Example:

1. Namespace example has the following annotation:

   apiVersion: v1
   kind: Namespace
   metadata:
     name: example
     annotations:
       scribe.anza-labs.dev/annotations: |
         app.kubernetes.io/name=example

2. The annotation is propagated to all resources within the namespace.
3. Later, the annotation is removed from the namespace:

   apiVersion: v1
   kind: Namespace
   metadata:
     name: example
     annotations:
       scribe.anza-labs.dev/annotations: ""

4. Scribe should detect the change and remove the app.kubernetes.io/name=example annotation from all relevant resources automatically.

Describe alternatives you've considered.

1. Manually removing annotations from resources when they are no longer needed, which can be time-consuming and error-prone in large environments.
2. Using custom scripts or jobs to periodically clean up outdated annotations, but this adds complexity and overhead.

Additional Information

No response

[Abiji-2020]

I am interested in this issue.

Proposed solution:

• We can develop the solution by integrating the watcher for the changes in the namespace annotation by using shared Informer and then we can reconcile for the updating?

[shanduur]

Hi @Abiji-2020! Thanks for reaching out.

I think that the changes to annotations on Namespace should be already watched, so the only thing left is to save annotations in something like scribe.anza-labs.devl/last-applied-annotations and update existing ones based on the diff between namespace and the aforementioned annotation.