Endless Loop when updating resources in handler

[Paulomart]

Hello everyone!

Im currently using kopf to create a custom k8s controller.

I have these resources in my cluster:

• my config-map foo contains some json config
• my deployment bar references foo as config-map-ref

My watches when a custom resource is deployed/updated/deleted:

• get the current deployment bar
• create a copy of the config-map foo and adjust values
• update the deployment bar to point to the copy of the config

This works great.

The problem arises when the deployment bar is deployed again (via kubectl apply e.g.). All changes that wore done by the controller are gone.
I attempted to fix this by creating a listener for the deployment. In that a would iterate other all my custom resources and proceed like before (When a custom resource is deployed/updated/deleted).

The code breaks down to something like this:

@kopf.on.resume('deployments', labels={'app': 'bar'})
async def on_deployment_resumed(name, meta, **kwargs):
    (...)
    deployment_patch_body = ...
    (...)
    apps.patch_namespaced_deployment(
        name=name,
        namespace=meta.namespace,
        body=deployment_patch_body,
    )

This will, of cause, cause an infinite loop in my controller.

My questions are:

1. What can I change to prvent the infinite loop?
2. Did I approche the problem wrong?
3. Is there a better way to do that?

I appreciate any hints!