Missing template file on update fails silently

[Zane Bitter]

When the template file for a template/facade/provider resource is not found in the new files list when doing a stack update, Heat silently falls back to using the existing template (i.e. so no change will be made).

The cause is that the update code shares the same code path for obtaining the template as the init code. The init code needs to have a fallback, so that loading the (parent) stack never fails, however in the update case it is undesirable.

[Rico Lin (rico-lin)]

Hi Zane, I have Problem with recreate this issue. There is a checker for the remote template, so It will fail with message "Could not fetch remote template \"file:///lib/template.yaml". Is it what you mean silently?
Can you provide your test procedure and test and sample script?
Thx

[Zane Bitter (zaneb)]

See bug 1452534 for more some details. It was originally found testing TripleO. The offending code is here: http://git.openstack.org/cgit/openstack/heat/tree/heat/engine/resources/template_resource.py?h=stable/kilo#n182

Note that the problem only occurs on update - you must have previously created the resource with a valid template, which it can then retrieve by calling self.nested().

[Rico Lin (rico-lin)]

https://review.openstack.org/#/c/192520/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/kilo
Review: https://review.openstack.org/193053

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/kilo
Review: https://review.openstack.org/194200

[OpenStack Infra (hudson-openstack)]

Change abandoned by Rico Lin (<email address hidden>) on branch: stable/kilo
Review: https://review.openstack.org/193053
Reason: This is a error branch I create
now fix with https://review.openstack.org/#/c/194200/
thanks for all comment

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/194200
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=a55f82715770a83e2ef3f9ce6f09c83ef5f13514
Submitter: Jenkins
Branch: stable/kilo

commit a55f82715770a83e2ef3f9ce6f09c83ef5f13514
Author: Rico Lin <email address hidden>
Date: Wed Jun 17 12:54:56 2015 +0800

    Missing template file on update fails silently

    When the template file for a template/facade/provider resource is
    not found in the new files list when doing a stack update, Heat
    silently falls back to using the existing template (i.e. so no
    change will be made).
    The cause is that the update code shares the same code path for
    obtaining the template as the init code. The init code needs to
    have a fallback, so that loading the (parent) stack never fails,
    however in the update case it is undesirable.

    Change-Id: Id12b63d9f04caba8e9325aed0ee2acf51ffe0c4c
    Closes-Bug: #1452520
    (cherry picked from commit 0c83c6f5ede0bf5d46779058ed5bea00629d5a3b)