[Starlingx-discuss] stx-openstack chart optionality

[Church, Robert]

Here's an update with regards to behavioral changes for optional charts/services.

Current behavior:
-----------------
With commit
https://opendev.org/starlingx/config/commit/e6b177eb93f85b5a4e53242214060c97728e2048,
Barbican and the Telemetry services (aodh, gnocchi, ceilometer, panko) are
disabled by default.

To enable these services, with the current builds, you must introduce a label to
a host as follows:
 * system host-label-assign controller-0 openstack-barbican=enabled
 * system host-label-assign controller-0 openstack-telemetry=enabled

This follows the existing pattern established for enabling ironic.


Future behavior:
----------------
It should be noted that this behavior is transitional as I have up for review:
https://review.opendev.org/#/c/671950/. With this update, each chart within an
application can be enabled/disabled from the command line prior to application
apply.

Again, by default: The following stx-openstack charts will be disabled on
application upload per the metadata packaged with the application:

disabled_charts:
- aodh
- barbican
- ceilometer
- gnocchi
- ironic
- panko

The current enablement state of a chart can be seen with:

$ system helm-override-show stx-openstack aodh openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack barbican openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack ceilometer openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack gnocchi openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack ironic openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack panko openstack | grep enabled
| attributes         | enabled: false                                         |

and a chart can be enabled/disabled with:

$ system help helm-chart-modify
usage: system helm-chart-modify [--enabled <true/false>]
                                <app name> <chart name> <namespace>

Modify helm chart attributes. This function is provided to modify system
behaviorial attributes related to a chart. Chart overrides are not managed
through this command.

Positional arguments:
  <app name>            Name of the application
  <chart name>          Name of the chart
  <namespace>           Namespace of the chart

Optional arguments:
  --enabled <true/false>
                        Chart enabled.

$ system helm-chart-modify stx-openstack barbican openstack --enable=true
+------------------+--------------------+
| Property         | Value              |
+------------------+--------------------+
| name             | barbican           |
| namespace        | openstack          |
| system_overrides | {u'enabled': True} |
+------------------+--------------------+

$ system helm-override-show stx-openstack aodh openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack barbican openstack | grep enabled
| attributes         | enabled: true                                          |
$ system helm-override-show stx-openstack ceilometer openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack gnocchi openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack ironic openstack | grep enabled
| attributes         | enabled: false                                         |
$ system helm-override-show stx-openstack panko openstack | grep enabled
| attributes         | enabled: false                                         |

When a chart is disabled, it is removed dynamically removed from its chart
group via the application's Armada manifest operator during override 
generation.

When a chart is enabled, additional system critera may be applied by a chart 
plugin to disable the chart if a specific system configuration is not met.

Thanks,
Bob