Open Stack

Excerpts from Pavlo Shchelokovskyy's message of 2016-05-19 15:28:03 +0300:
> Hi all,
> 
> I have a question re FOSS licenses interplay. I am pretty sure that
> OpenStack community (e.g. openstack-ansible) has already faced such
> questions and I would really appreciate any advice.
> 
> We are developing a new ansible-based deployment driver for Ironic [0] and
> would like to use some parts of ansible-lib Python API to avoid boilerplate
> code in custom Ansible modules and callbacks we are writing, and in the
> future probably use Ansible Python API to launch playbooks themselves.
> 
> The problem is Ansible and ansible-lib in particular are licensed under GPL
> v3 [1] "or later" [2]. According to [3] Apache 2.0 license is only one way
> compatible with GPL v3 (GPL v3-licensed code can include Apache
> 2.0-licensed code, but not vice versa).
> 
> I am by far not a legal expert, so my questions are:
> 
> Does it mean that the moment I do "from ansible import ..." in my Python
> code, which AFAIU means I am "linking" to it, I am required to use a
> GPLv3-compliant license for my code too (in particular not Apache 2.0)?
> What problems might that imply in respect with including such code in an
> OpenStack project (e.g. submitting it to Ironic repo) and distributing the
> project?

Yes that's what it means. You can write modules in any license you want
because AnsibleModule is BSD 2-clause, but plugins must be GPLv3.

> If there are indeed problems with that, would it be safer to keep the code
> in a separate project and also distribute it separately?
> Even when distributed separately, will merely using (dynamically importing
> at run-time) a GPLv3-licensed driver from ApacheV2-licensed Ironic
> constitute any license violation?
> 

I think your options are to make it function without the plugins, and
distribute just them separately (so a bare bones version comes with
Ironic, but it works better w/ the GPLv3 plugins), or just distribute
the whole thing separately.

Long term, you might approach Ansible about possibly making their plugin
interface LGPL so that people can write non-GPL plugins. But, it may be
part of a broader strategy to ensure that contribution happens in the
open. As an OSS hippie, I applaud them for choosing a strong copyleft
license. :)