backends.pp should not override already enabled_backends

[Roman Sokolkov]

In current implementation cinder::backends will override all existing values in [DEFAULT]/enabled_backends. If backends managed from different manifests it doesn't allow to keep existing, while adding new.

Probably it would be better to use ini_subsetting instead of cinder_config.

Steps to reproduce:
0) Let's say you want to deploy two Cinder backends (in my case one by Fuel plugin, but generally it can be standalone manifest)
1) Create new plugin that uses cinder::backends to add backend X
2) Deploy MOS 9.0 with new plugin and LVM or Ceph backend

Actual result:
[DEFAULT]/enabled_backends will be overwritten by plugin and by Fuel.
Finally it will have either Backend X or Fuel backend depending on executing order.

Expected result:
[DEFAULT]/enabled_backends will have both Backend X and Fuel backends

[Dmitry Klenov (dklenov)]

@Roman, can you please add steps to reproduce?

[Roman Sokolkov (rsokolkov)]

@Dmitry, done.

[Ivan Berezovskiy (iberezovskiy)]

@Roman, I don't think we should switch to ini_subsetting. Please take a look on this lines: https://github.com/openstack/fuel-library/blob/master/deployment/puppet/openstack_tasks/manifests/roles/cinder.pp#L91-L110 - this gives you first backend name:
https://github.com/openstack/fuel-library/blob/master/deployment/puppet/openstack_tasks/manifests/roles/cinder.pp#L226

You just need to pass you value for backend name in second element of array. I think you need to fix your manifest only.

[Takashi Kajinami (kajinamit)]

There is no issue with puppet-cinder's implementation mentioned.
I'll close this now.