refs attribute of ResourceGroup does not support indexing

[Pavlo Shchelokovskyy]

minimal reproducer:

$ cat refs.yaml
heat_template_version: 2015-04-30
resources:
  group:
    type: OS::Heat::ResourceGroup
    properties:
      count: 2
      resource_def:
        type: OS::Heat::RandomString
outputs:
  allrefs:
    value: { get_attr: [ group, refs ] }
  oneref:
    value: { get_attr: [group, refs, 0 ] }

$ heat stack-create refs -f refs.yaml
$ heat stack-list
+--------------------------------------+------------+-----------------+----------------------+
| id | stack_name | stack_status | creation_time |
+--------------------------------------+------------+-----------------+----------------------+
| 5a7dec43-ebe8-46e5-a1e0-46871bd67da4 | refs | CREATE_COMPLETE | 2015-03-20T14:07:31Z |
+--------------------------------------+------------+-----------------+----------------------+

$ heat output-show refs allrefs
[
  "a4t2y5IuYLJzEZRVdFCEKhAnaWfI9vTi",
  "5HwxHxZN41J78l42OKH07igJif8Pk7tn"
]

$ heat output-show refs oneref
[
  "a4t2y5IuYLJzEZRVdFCEKhAnaWfI9vTi",
  "5HwxHxZN41J78l42OKH07igJif8Pk7tn"
]

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/168301

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/168301
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=553727cfd017c7a01c8eaa24a43c807ad2202855
Submitter: Jenkins
Branch: master

commit 553727cfd017c7a01c8eaa24a43c807ad2202855
Author: tyagi <email address hidden>
Date: Fri Mar 27 04:11:50 2015 -0700

    Make 'refs' attribute of ResourceGroup resource indexable

    With this change 'refs' attribute of the ResourceGroup resource will
    support indexing.

    Change-Id: I7715897091a55ed333e4b07bd1ad38bd4d8aa019
    Closes-Bug: #1434586

[Jeffrey Guan (double12gzh)]

I tested this on heat_template_version: '2014-10-16' and found that this fixed is not included.

I am wondering if there is any workaround for this issus on heat_template_version: '2014-10-16'?

Thank you very much.

[Rabi Mishra (rabi)]

I think you want this work with Juno. However, Juno is EOL[1], hence this can't be back-ported.

[1] http://docs.openstack.org/releases/

[Jeffrey Guan (double12gzh)]

Yes, I want to use Juno. Thank you very much for your valuable info.

I will find a workaround for this on Juno.

Thank you very much.

[carl (gsl0610)]

We can update the code in heat with the fix under heat/engine/resources/openstack/heat/resource_group.py.
https://review.openstack.org/168301