On Tue, Jan 28, 2014 at 2:41 AM, Ariel T. Glenn <ariel(a)wikimedia.org> wrote:
Hi puppet wranglers,
We're trying to refactor the WMF puppet manifests to get rid of reliance
on dynamic scope, since puppet 3 doesn't permit it. Until now we've
done what is surely pretty standard pupet 2.x practice: assign
values to a variable in the node definition and pick it up in the
class from there dynamically. Example: we set $openstack_version
to a specific version depending on the node, and the nova and
openstack classes do different things depending on that value.
Without dynamic scoping that's no longer possible, so I'm wondering
what people are doing in the real world to address this, and
what best practices are, if any. Hiera? Some sort of class
parameterization? Something else?
It should go without saying that we'd like not to have to massively
rewrite all our manifests, if possible.
In puppet3 variables assigned in the node are still global. It's the only
place other than facts (or hiera) that you can assign them and have their
scope propagate. So, this'll continue working. I think the future path is
surely to use hiera rather than assigning variables in role classes (and
making tons of role classes based on realm/cluster/site/etc).