pre-deletion resource hooks

[adabuleanu]

Summary

Please add support for pre/post delete hook.

Motivation

Current resource hooks do not support pre/post deletion hooks. Here is a [list with supported hooks compared to helm hooks|https://argo-cd.readthedocs.io/en/stable/user-guide/helm/#helm-hooks]. There are many use cases where you want to run addtional actions before or after an ArgoCD Application is deleted.

Proposal

Functionality should be similar to what [helm provides for deletion hooks|https://helm.sh/docs/topics/charts_hooks/]

[mrnvzch]

This might of interest, though I don't think you'll find a workaround there.

[eugenenelou]

The post-delete hook has been implemented.
It would be very useful to also have the pre-delete hook, to cleanup things outside of the application before deleting it.

[blakepettersson]

Indeed, #16595 solved the PostDelete case

[ofirc]

Hi, are there any plans to support/implement that, or explain possible work-arounds for that?

[blakepettersson]

@ofirc no current plans nor workarounds. I guess it wouldn't be too hard to implement pre-delete hooks, but someone has to do the work.

[Softyy]

@blakepettersson does this proposal fall into the Accepted state, would a PR for pre-delete hooks be reviewed?