Post-Delete Hook support mutate Application object

[llavaud]

Describe the bug

The recent Post-Delete hook support PR, mutate the Application object when refreshing by adding two finalizers if a resource have a "helm.sh/hook": post-delete annotation.
In an apps of apps context it causes unnecesssary reconciliations due to object updated:

{"api-version":"argoproj.io/v1alpha1","application":"myRootApp","cluster-name":"myCluster","fields.level":0,"kind":"Application","level":"debug","msg":"Requesting app refresh caused by object update","name":"myApp","namespace":"argo-cd","server":"myServer","time":"2024-03-07T08:14:40Z"}

To Reproduce

Create an Application that deploy another Application, in the nested Application deploy a resource that have a "helm.sh/hook": post-delete annotation. Wait for the 3m default refresh interval and search for the Requesting app refresh caused by object update debug log line.

Expected behavior

Do not mutate the Application object or at least maybe automaticaly ignore thoses finalizers like it is currently done for the metadata fields generation and resourceVersion

Version

argocd: v2.10.2+fcf5d8c
  BuildDate: 2024-03-01T21:24:51Z
  GitCommit: fcf5d8c2381b68ab1621b90be63913b12cca2eb7
  GitTreeState: clean
  GoVersion: go1.21.3
  Compiler: gc
  Platform: linux/amd64

[llavaud]

A possible workaround:

resource.customizations.ignoreDifferences.argoproj.io_Application: |
  jqPathExpressions:
    - .metadata.finalizers[]? | select(. == "post-delete-finalizer.argocd.argoproj.io" or . == "post-delete-finalizer.argocd.argoproj.io/cleanup")
    - if (.metadata.finalizers | length) == 0 then .metadata.finalizers else empty end

[llavaud]

@alexmt Hello, can I have your opinion on this please ? do you consider it as a bug or normal behavior ?

[msvechla]

we are experiencing the same issue. The workaround above works, but it looks like this should be handled on argocd side

[didlawowo]

A possible workaround:

resource.customizations.ignoreDifferences.argoproj.io_Application: |
  jqPathExpressions:
    - .metadata.finalizers[]? | select(. == "post-delete-finalizer.argocd.argoproj.io" or . == "post-delete-finalizer.argocd.argoproj.io/cleanup")
    - if (.metadata.finalizers | length) == 0 then .metadata.finalizers else empty end

how can i make that in config map ?

[llavaud]

A possible workaround:

resource.customizations.ignoreDifferences.argoproj.io_Application: |
  jqPathExpressions:
    - .metadata.finalizers[]? | select(. == "post-delete-finalizer.argocd.argoproj.io" or . == "post-delete-finalizer.argocd.argoproj.io/cleanup")
    - if (.metadata.finalizers | length) == 0 then .metadata.finalizers else empty end

how can i make that in config map ?

not sure to understand your question, the example is what you must add to the argocd-cm ConfigMap

[nbarrientos]

In case this was useful somehow, here it is a good example of a "real world" chart triggering this:

https://github.com/kubernetes-sigs/node-feature-discovery/blob/6030c974d38ed9a1e4592f0f133d64e27d3c50a7/deployment/helm/node-feature-discovery/templates/post-delete-job.yaml#L8-L10

which is used in NVIDIA's gpu operator:

https://github.com/NVIDIA/gpu-operator/blob/main/deployments/gpu-operator/Chart.yaml#L21

[andrii-korotkov-verkada]

@nbarrientos, which ArgoCD version are you using when reproducing?

[nbarrientos]

@andrii-korotkov-verkada Hi! v2.12.6+4dab5bd