[PROPOSAL] lock juju down to using charms from LTS and latest release only

[Robbie Williamson]

Hi all,

With all the discussion about rolling release, I got to thinking about
our charms and how they tie to releases.  I wanted to propose that we
limit the releases supported by juju to LTS plus the latest release.  My
reasoning is that we need to ensure better charm consistency for
supported releases, and the current approach isn't working well[1].
With this proposal, we'd only ever need to care about two releases
(maybe three):

  13.04: 12.04LTS (juju doesn't work with 10.04LTS) and 13.04
  13.10: 12.04LTS and 13.10
  14.04: 12.04LTS and 14.04LTS
  14.10: 12.04LTS, 14.04LTS, 14.10
   *or*
  14.10: 14.04LTS and 14.10

I'm not sure we need to support two LTSes come 14.10, but then that
means existing deployments with 12.04 are forced to upgrade to the next
LTS to get continued free updates and support for their charms.  I think
from a coding and complexity perspective, simply saying latest LTS plus
current release is best.  Plus, for the 14.04 LTS release we would keep
12.04 supported for 6 months until 14.10, allowing time for updates.

Thoughts?

-Robbie

[1]http://jujucharms.com/charms/oneiric
   http://jujucharms.com/charms/precise
   http://jujucharms.com/charms/quantal

-- 
Robbie Williamson <robbie at ubuntu.com>
robbiew[irc.freenode.net]

"Don't make me angry...you wouldn't like me when I'm angry."
 -Bruce Banner