openstack-ansible/doc
Nolan Brubaker 7b288eafbe Use in-tree env.d files, provide override support
In past versions, upgrading OpenStack-Ansible lead to contention between
the code base and deployer customizations when env.d files were changed.
Deployers were encouraged to make their customizations, while the
project needed to sometimes adjust architecture. Detecting these
conflicts in an automated way was difficult, since the files were simple
dictionaries and lists, leaving no metadata to describe intent for the
changes.

This change modifies the dynamic inventory system to first use the
in-tree env.d directory as the base environment, then reads in files
from the /etc/openstack_deploy/env.d directory and updates existing keys
with the new values. In this way, the OSA project can modify the
environment and deployers can customize the environment without directly
manipulating the same files.

As part of this change, the env.d directory was moved in to the
playbooks/inventory directory, in order to reduce the path manipulation
done inside of the dynamic_inventory.py script. The example files were
left in the etc/openstack_deploy directory for reference.

Note that this change supports deleting elements by specifying a
empty value, such as an empty list or an empty dictionary.

When overriding, only the path to the values that changed is necessary.
For example, changing the 'is_metal' property for cinder only needs the
following in /etc/openstack_deploy/env.d/cinder.yml:

    container_skel:
      cinder_volumes_container:
        properties:
          is_metal: false

This is instead of the entirity of the container_skel dict or even the
other top-level dicts.

For AIO/gate scenarioes, the env.d copy logic has been removed, as it is
now redundant.

Change-Id: Ic637fa385fd3fec7365fb9bc5e0ff54a7f4c8bee
2016-07-01 16:40:28 +00:00
..
source Use in-tree env.d files, provide override support 2016-07-01 16:40:28 +00:00
Makefile Rename everything for the osad to osa name change 2015-09-12 02:31:21 +01:00