ArgoCD is not fully reproducing kubectl apply side-effects: not creating a managedFields entry

[reegnz]

Checklist:

• I've searched in the docs and FAQ for my answer: https://bit.ly/argocd-faq.
• I've included steps to reproduce the bug.
• I've pasted the output of argocd version.

Describe the bug

When doing client-side apply with kubectl, the kubectl client also sets a managedFields entry called kubectl-client-side-apply. This is kept up-to-date to match the kubectl.kubernetes.io/last-applied-configuration.

When starting to move from deploying with kubectl apply to deploying the raw manifests with argocd, the kubectl-client-side-apply field manager is not updated anymore. There's also no other managedFields entry created that says argocd-controller-client-side-apply or similar for example.

To maintain compatibility with kubectl when deploying raw manifests, please make sure that the operation is tracked in managedFields as well, to maintain an element of least surprise.

To Reproduce

cat <<-EOF | kubectl apply -f -
apiVersion: v1
kind: ConfigMap
metadata:
  name: test
data:
   test: test
EOF

The managed fields is automatically updated:

❯ k get cm test -o yaml --show-managed-fields
apiVersion: v1
data:
  test: test
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"test":"test"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"test","namespace":"default"}}
  creationTimestamp: "2024-01-10T13:02:34Z"
  managedFields:
  - apiVersion: v1
    fieldsType: FieldsV1
    fieldsV1:
      f:data:
        .: {}
        f:test: {}
      f:metadata:
        f:annotations:
          .: {}
          f:kubectl.kubernetes.io/last-applied-configuration: {}
    manager: kubectl-client-side-apply
    operation: Update
    time: "2024-01-10T13:02:34Z"
  name: test
  namespace: default
  resourceVersion: "88025"
  uid: 2554be5e-f3b7-4657-b6a1-5a57becc350a

If the same resource is created with ArgoCD, there is no managedFields.

Expected behavior

Whenever argocd creates/updates a resource, a managedFields entry should reflect the same data that the kubectl.kubernetes.io/last-applied-configuration annotation contains.

Version

v2.9.3

[reegnz]

For reference, helm create/update a managedFields entry (with manager name helm) when applying manifests: helm/helm#9870