This PR adds a Finalizer for VolumeSnapshotContent.
If the VolumeSnapshotContent is bound to a VolumeSnapshot,
the VolumeSnapshotContent is being used and cannot be
deleted.
This PR also adds a Finalizer for VolumeSnapshot.
If a volume is being created from the snapshot,
the VolumeSnapshot is being used and cannot be deleted.
This PR adds DeletionPolicy which describes a policy for end-of-life maintenance of volume snapshot contents.
There are two types of policies, delete and retain. By default, the
policy is delete. In this case, when volume snaphsot is deleted, the
volume snapshot content for it should be deleted, as well as the
physical snapshot. If the policy is set the retain, the volume snapshot
content will remain even if the volume snapshot it binds to is deleted.
In VolumeSnapshotContent, if the CSI driver does not match the plugin's,
the controller should skip this content instead of always processing it.
This PR also add a few tests related to snapshot and content static
binding.
During binding, if content specify its bound snapshot uid and it
does not match the snapshot's uid, the content object and also the
physical snapshot will be deleted. In this case, the controller will
treat the content as an orphan content because its snapshot object does
not exist (deleted) any more.
This PR fixed the issue of not updating the snapshot restore size after
snapshot is created. Before snapshot is ready, the returned size might
not be accurate. So we need to keep updating the snapshot size during
checking the snapshot status.
