fact for datasets/volumes

[tuxmaster5000]

Use Case

If you want to create encrypted datasets/volumes automatically, the key material may only be generated during the initial setup.
This requires a fact that makes it possible to test for the presence of datasets/volumes in a pool so that the key material is not generated again.

Describe the Solution You Would Like

An simple puppet like this:
$facts['zfs']['']['<volume/dataset name>']
Optional the fact can provide additional information about the pool and the volumes/datasets
So that this code will work:

if $facts['zfs']['foo']['bar'] {
exec { 'create_key_material':
....
}
zfs { 'bar':
...
require => Exec[...]
}
}

Describe Alternatives You've Considered

Do this manual on the server, because the key material will only present temporary on an ram disk on the server.
So the "creates" of exec will not an option.