Add annotation handling of new annotation helm.sh/update-policy with values recreate-on-conflict and recreate-on-invalid values to better deal with the following cases.
The server responds with 'invalid' e.g. if a certain resource contains an immutable field, which cannot be patched or updated by a PUT. In theses cases it can be helpful to delete the resource and recreate it. Examples for theses cases are:
* roleRef in RoleBinding
* spec.clusterIP in Service
* parameters in StorageClass
If a chart developer has made sure that recreating a resource is safe, the annotation can be added to a resource template. Alternatively a user may add the annotation manually to an existing resource to allow Helm to recreate a certain resource.
Adding the new annotation in general by default or changing the default behaviour of Helm is not a good idea, since deletion and recreation of certain resources can lead to an unwanted or undefined state as described in detail in https://github.com/helm/helm/pull/7431#issuecomment-666735299:
"[...] selectively deleting/re-creating volume-backed resources (Secrets, Services, ConfigMaps, PVCs) without touching the Deployment. If a Persistent Volume Claim is deleted and re-created, there is a risk that an application (Deployment) consuming that Persistent Volume Claim will not receive the new volume's mount point. The same can be said for Secrets, Configmaps, Services, and other resources which are deployed and relied upon by another resource. Environment variables populated in a Deployment from a Service won't be updated until the Pods are destroyed."
Closes#7082.
Signed-off-by: Daniel Strobusch <1847260+dastrobu@users.noreply.github.com>
Daniel Strobusch
0b58239b51