Comment 7 for bug 1700664

Reviewed: https://review.openstack.org/477695
Committed: https://git.openstack.org/cgit/openstack/tripleo-heat-templates/commit/?id=f572b764f18cb3c6b54e24c1015a7e4dfcefd65f
Submitter: Jenkins
Branch: master

commit f572b764f18cb3c6b54e24c1015a7e4dfcefd65f
Author: Ben Nemec <email address hidden>
Date: Mon Jun 26 16:58:13 2017 -0500

    Add validation check for divergent parameter definitions

    Many of our parameters are defined in multiple templates, but
    currently there is no easy way of checking that all of those
    definitions match. It can be confusing when a parameter is defined
    one way in one file and another way in a different file. For example,
    the NovaWorkers description is:

    Number of workers for Nova API service.

    and

    Number of workers for Nova Placement API service.

    and

    Number of workers for Nova Conductor service.

    Which is it actually? All of them. That one parameter controls
    the workers for all of the nova services, and its description should
    reflect that, no matter which template you happen to look at.

    This change adds a check to yaml-validate.py to catch these sorts of
    inconsistencies and allow us to eventually prevent new ones from
    getting into the templates.

    An exclusion mechanism is included because there are some parameter
    definitions we probably can't/shouldn't change. In particular, this
    includes the network cidrs which are defaulted to ipv4 addresses in
    the ipv4 net-iso templates and ipv6 in the ipv6 templates. It's
    possible a user would be relying on one of those defaults in their
    configuration, so if we change it they might break.

    To get around that, the tool explicitly ignores the default field of
    those parameters, while still checking the description and type fields
    so we maintain some sanity. There may be other parameters where this
    is an issue, but those can be added later as they are found.

    For the moment any inconsistencies are soft-fails. A failure message
    will be printed, but the return value will not be affected so we can
    add the tool without first having to fix every divergent parameter
    definition in tripleo-heat-templates (and there appear to be plenty).
    This will allow us to gradually fix the parameters over time, and
    once that is done we can make this a hard-fail.

    Change-Id: Ib8b2cb5e610022d2bbcec9f2e2d30d9a7c2be511
    Partial-Bug: 1700664