orchestra provider now respects ubuntu-series constraint

orchestra provider now respects ubuntu-series constraint

This is done by setting a new system profile before powering on the machine;
and assumes that the Cobbler system profiles created as part of the
ubuntu-orchestra-server install actually exist. Anecdotal evidence suggests
that people really don't mess with the distros and profiles available (they
just set up their systems and go) and so I consider the impact of this
drawback to be extremely limited.

Furthermore, while it is possible to extract real arch and series info from
cobbler (ie we can get a system's arch from its profile's distro, and we can
partially match new profiles by checking the distro's series and arch) this
is not enough to select an actual profile without depending on some
convention: we either have to infer the presence of the juju preseed from
the profile name (as I do currently) or to check the profile itself for
a magic string (ie the path to the juju preseed).

So: we depend on orchestra install conventions, whatever we do; and IMO it's
cleanest and simplest to actually embrace that and save all the mucking
about with distros and profiles.

https://code.launchpad.net/~fwereade/juju/orchestra-series-constraints/+merge/101670

(do not edit description out of merge proposal)

[fwereade, 2012-04-12 01:14:36]

Please take a look.

[fwereade, 2012-04-12 01:25:54]

Please take a look.

[fwereade, 2012-04-12 01:31:09]

Please take a look.

[hazmat, 2012-04-12 17:59:20]

lgtm

[fwereade, 2012-04-12 18:57:38]

*** Submitted:

orchestra provider now respects ubuntu-series constraint

This is done by setting a new system profile before powering on the machine;
and assumes that the Cobbler system profiles created as part of the
ubuntu-orchestra-server install actually exist. Anecdotal evidence suggests
that people really don't mess with the distros and profiles available (they
just set up their systems and go) and so I consider the impact of this
drawback to be extremely limited.

Furthermore, while it is possible to extract real arch and series info from
cobbler (ie we can get a system's arch from its profile's distro, and we can
partially match new profiles by checking the distro's series and arch) this
is not enough to select an actual profile without depending on some
convention: we either have to infer the presence of the juju preseed from
the profile name (as I do currently) or to check the profile itself for
a magic string (ie the path to the juju preseed).

So: we depend on orchestra install conventions, whatever we do; and IMO it's
cleanest and simplest to actually embrace that and save all the mucking
about with distros and profiles.

R=hazmat
CC=
https://codereview.appspot.com/6012045