K8SPG-714: fix panic

[pooknull]

https://perconadev.atlassian.net/browse/K8SPG-714

DESCRIPTION

This PR fixes the panic on update to 2.6.0 operator

Also it fixes following issues:

• handles conflict error on pgbackup status update, which caused following log message: update PGBackup status: Operation cannot be fulfilled on perconapgbackups.pgv2.percona.com \"XXX\": the object has been modified
• resources not being applied to patroni-version-check pod
• reduces patroni-version-check pod's terminationGracePeriod to 5
• fixes percona.com/delete-backup not being removed after backup completion

CHECKLIST

Jira

• Is the Jira ticket created and referenced properly?
• Does the Jira ticket have the proper statuses for documentation (Needs Doc) and QA (Needs QA)?
• Does the Jira ticket link to the proper milestone (Fix Version field)?

Tests

• Is an E2E test/test case added for the new feature/change?
• Are unit tests added where appropriate?

Config/Logging/Testability

• Are all needed new/changed options added to default YAML files?
• Are all needed new/changed options added to the Helm Chart?
• Did we add proper logging messages for operator actions?
• Did we ensure compatibility with the previous version or cluster upgrade process?
• Does the change support oldest and newest supported PG version?
• Does the change support oldest and newest supported Kubernetes version?

[gkech]

Commenting only to confirm that I understand this fully. What we want to do with assigning this to nil is effectively to be able to remove the finalizer when RunFinalizer is executed

	if err := f(ctx, obj); err != nil {
		if errors.Is(err, ErrFinalizerPending) {
			return false, nil
		}
		return false, errors.Wrapf(err, "run finalizer %s", finalizer)
	}

	if controllerutil.RemoveFinalizer(obj, finalizer) {
		log.Info("Removing finalizer", "name", finalizer)
		if err := cl.Patch(ctx, obj, client.MergeFrom(orig)); err != nil {
			return false, errors.Wrap(err, "remove finalizers")
		}
	}

and more specifically, when ☝🏽 these are executed, is that correct?

[pooknull]

You are correct. If we don’t set it to nil, the finalizer will fail, preventing its removal. The deleteBackupFinalizer function checks whether pgCluster is nil, and if so, it returns successfully:

percona-postgresql-operator/percona/controller/pgbackup/controller.go

Lines 327 to 331 in 942c3fd

	func deleteBackupFinalizer(c client.Client, pg *v2.PerconaPGCluster) func(ctx context.Context, pgBackup *v2.PerconaPGBackup) error {
	return func(ctx context.Context, pgBackup *v2.PerconaPGBackup) error {
	if pg == nil {
	return nil
	}

[gkech]

⭐ thanks!

[egegunes]

please add comments to new code added into files in internal/, it'll be helpful when we do upstream merges

[JNKPercona]

Test name	Status
custom-extensions	passed
custom-tls	passed
demand-backup	passed
finalizers	passed
init-deploy	passed
monitoring	passed
one-pod	passed
operator-self-healing	passed
pitr	passed
scaling	passed
scheduled-backup	passed
self-healing	passed
sidecars	passed
start-from-backup	passed
tablespaces	passed
telemetry-transfer	passed
upgrade-consistency	passed
upgrade-minor	passed
users	passed
We run 19 out of 19

commit: 9fc01f5
image: perconalab/percona-postgresql-operator:PR-1032-9fc01f539