I have one pre-install hook which creates a dynamic PVC and looks like this
kind: PersistentVolumeClaim
metadata:
name: my-dynamic-pv
annotations:
"helm.sh/resource-policy": keep
"helm.sh/hook": "pre-install"
spec:
storageClassName: {{ .Values.persistence.storageClass }}
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1GiI want to preserve the same PVC across restarts that's why I have provided "helm.sh/resource-policy": keep. I am able to create the PVC with the pre-install hook the very first time I start my service. But the subsequent installs/restarts are failing with error Error: persistentvolumeclaims "my-dynamic-pv" already exists.
Is there a way to ignore this failure and continue with the helm installation?
You can use helm lookup function to check the existence of the pvc before creating it.
{{- $mypvc := (lookup "v1" "PersistentVolumeClaim" .Release.Namespace (printf "my-
dynamic-pv")) }}
{{- if not $mypvc }}
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: my-dynamic-pv
annotations:
"helm.sh/resource-policy": keep
"helm.sh/hook": "pre-install"
spec:
storageClassName: {{ .Values.persistence.storageClass }}
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
{{- end -}}More on helm lookup funtion - Helm template functions
I'm using helm 3.2.1. You will probably need a near version to use the lookup function.
Use --no-hooks flag to the helm command to ignore hooks.
$ helm install --help | grep "no-hooks"
--no-hooks prevent hooks from running during install
$ helm install <NAME> <CHART> --no-hooks