get_att non-obvious failure on 2013-05-23 HOT

[Steven Hardy]

If you accidentally get your template version wrong, e.g:

  heat_template_version: 2013-05-23

  resources:
    random_group:
      type: OS::Heat::ResourceGroup
      properties:
        count: 2
        resource_def:
          type: OS::Heat::RandomString

  outputs:
    all_values:
      value: {get_attr: [random_group, attributes, value]}

You get:

  "output_error": "The Referenced Attribute (random_group attributes) is incorrect.",

This is quite confusing, since the referenced attribute exists for the resource, the error is we're passing path components to a version of get_att which doesn't support it AFAICT.

I imagine path based lookup of nested stacks will fail in a similar way, quite puzzling until you spot the problem, so a better error and maybe note in the attribute documentation should be added.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/143156

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/143156
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=0d746a9dde3cfcccfb3fe84a9671d3b6cca595b1
Submitter: Jenkins
Branch: master

commit 0d746a9dde3cfcccfb3fe84a9671d3b6cca595b1
Author: Steven Hardy <email address hidden>
Date: Fri Dec 19 19:05:34 2014 +0000

    Clarify "attributes" support status for ResourceGroup

    This was added during juno but not documented as such. Also clarify
    that latest HOT is required, or the path based get_attr call won't
    work (currently in a really non-obvious way..)

    Change-Id: I14f600cfc9f0f56b2acf366ef7fcbef25d16f003
    Partial-Bug: #1404360

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/146836

[Thomas Spatzier (thomas-spatzier)]

Is anyone aware of another place that we need to fix? Or can we close this?

Steven fixed the immediate issue in ResourceGroup and I fixed a related documentation issue.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/146836
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=c340a2b79bed32e5533c5c55e969250c6c90e8e0
Submitter: Jenkins
Branch: master

commit c340a2b79bed32e5533c5c55e969250c6c90e8e0
Author: Thomas Spatzier <email address hidden>
Date: Tue Jan 13 13:05:47 2015 +0100

    Fix template version in composition section

    The composition section uses some example templates that only work
    correctly with the latest heat_template_version 2014-10-16 as has
    been pointed out in a comment on review
    https://review.openstack.org/#/c/146454

    This change simply pulls all changes from the review mentioned
    above to the composition section in the heat repository.

    Change-Id: I2fcc64f80e1f5a1109ba31edec92912e8e55830d
    Partial-Bug: #1404360

[Thomas Spatzier (thomas-spatzier)]

Talked to Steven on IRC and we think this bug is addressed now and can be closed.