Comment 20 for bug 1731349

Reviewed: https://review.openstack.org/530975
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=4a3a1ad15bdcfd67e0548481c70545e41a9476d9
Submitter: Zuul
Branch: master

commit 4a3a1ad15bdcfd67e0548481c70545e41a9476d9
Author: Zane Bitter <email address hidden>
Date: Mon Jan 8 17:23:12 2018 -0500

    Fix attribute caching in Heat AutoScalingGroup

    Attributes for an individual resource in an OS::Heat::AutoScalingGroup can
    be retrieved using the attribute name 'resource.<index>'. Because we were
    treating the index as a resource name when generating the template, we
    would never generate an output in the nested template that referenced the
    resource's attribute, so it wouldn't get cached. Since we can't know the
    indices ahead of time, the only way to cache these is to do it for all
    resources in the group - which is the same data cached by the equivalent
    'outputs' attribute.

    We also need to take into account both possible forms of syntax:

        [<asg_name>, resource.<index>.<attr_name>, ...]

    or:

        [<asg_name>, resource.<index>, <attr_name>, ...]

    Change-Id: I1d2898cdd4759b1bb9de1896a40056685e728f44
    Closes-Bug: #1737047
    Partial-Bug: #1731349
    Related-Bug: #1660831