openstack
/
heat
Code Issues Proposed changes

Warn against API calls in plugin guide 

API calls raising uncaught exceptions have previously caused problems,
especially when deleting stacks or cleaning up after a stack's partial
deletion. This commit explicitely documents this pitfall.

Change-Id: If86ef0deb5b8eaa1a0665c07bfddcfe52994f249
Related-Bug: #1554625
This commit is contained in:
Johannes Grassler 2016-03-30 09:55:37 +02:00
parent 9d03183ab5
commit d263687f84
1 changed files with 18 additions and 0 deletions
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18
doc/source/developing_guides/pluginguide.rst
View File

@ -523,6 +523,24 @@ Delete
is deleted; ``False`` otherwise.
:raise: any ``Exception`` if the delete operation failed.
Resource Dependencies
+++++++++++++++++++++
Ideally, your resource should not have any 'hidden' dependencies, i.e. Heat
should be able to infer any inbound or outbound dependencies of your resource
instances from resource properties and the other resources/resource attributes
they reference. This is handled by
``heat.engine.resource.Resource.add_dependencies()``.
If this is not possible, please do not simply override `add_dependencies()` in
your resource plugin! This has previously caused `problems
<https://bugs.launchpad.net/heat/+bug/1554625>`_ for multiple operations,
usually due to uncaught exceptions, If you feel you need to override
`add_dependencies()`, please reach out to Heat developers on the `#heat` IRC
channel on FreeNode or on the `openstack-dev
<mailto:openstack-dev@lists.openstack.org>`_ mailing list to discuss the
possibility of a better solution.
Registering Resource Plug-ins
+++++++++++++++++++++++++++++
To make your plug-in available for use in stack templates, the plug-in must