provider/maas: instance and storage uniqueness

provider/maas: instance and storage uniqueness

This merges the following branches from trunk.
Fixes https://launchpad.net/bugs/1229275

------------------------------------------------------------
revno: 1990 [merge]
author: Roger Peppe <roger.peppe@canonical.com>
committer: Tarmac
branch nick: juju-core
timestamp: Wed 2013-10-16 13:12:52 +0000
message:
  [r=rogpeppe] provider/maas: do not use environ-uuid
  
  As pointed out by fwereade, it could be
  confusing to have two things in the system
  that both purport to be a uuid for the environ.
  
  Also make the MAAS EnvironProvider.Validate
  check that we're not changing the maas-agent-name.
  
  https://codereview.appspot.com/14741045/
------------------------------------------------------------

revno: 1989 [merge]
author: Julian Edwards <julian.edwards@canonical.com>
committer: Tarmac
branch nick: juju-core
timestamp: Wed 2013-10-16 06:11:50 +0000
message:
  [r=axwalk],[bug=1081247],[bug=1229275] Use the environment's UUID as a file prefix for all files in MAAS private storage to prevent different environments from overlapping.
------------------------------------------------------------

------------------------------------------------------------
revno: 1985 [merge]
author: Gavin Panella <gavin@gromper.net>
committer: Tarmac
branch nick: juju-core
timestamp: Wed 2013-10-16 01:56:42 +0000
message:
  [r=wallyworld] Use environment-uuid when interacting with MAAS
  
  The environment-uuid is passed - as agent_name - to MAAS when acquiring
  and listing nodes. This will allow multiple Juju environments to coexist
  in a single MAAS user's account.
  
  In addition, it prevents environment-uuid from being set in
  environments.yaml, and returns an appropriate error message. This is
  intended to stop people from inadvertently clobbering existing
  environments.
  
  It also starts cleaning up MAAS's providerSuite by dropping the environ
  attribute in favour of makeEnviron(). The former was initialised to a
  half-working environ that caused strange test failures.
  
  https://codereview.appspot.com/14644045/
------------------------------------------------------------
revno: 1984 [merge]
author: Gavin Panella <gavin@gromper.net>
committer: Tarmac
branch nick: juju-core
timestamp: Tue 2013-10-15 17:03:22 +0000
message:
  [r=gz] provider/maas: Add environment UUID
  
  We need a way to uniquely identify those machines in MAAS belonging to
  a Juju environment. Until now Juju's MAAS provider has assumed that
  all the machines that are allocated, are allocated to the environment
  that Juju is working with. This is obviously wrong, and can be
  disastrous.
  
  This is the first part of work on the MAAS provider to use a unique
  identifier for an environment. MAAS will record this identifier
  (called 'agent_name' in MAAS) and allow its use for filtering.
  This branch merely adds the UUID to the environment's config.
  
  https://codereview.appspot.com/14696043/
  
  R=rogpeppe, rvb

https://code.launchpad.net/~rogpeppe/juju-core/454-1.16-maas-changes/+merge/191413

(do not edit description out of merge proposal)

[rog, 2013-10-16 13:42:08]

Please take a look.

[mue, 2013-10-16 14:04:52]

LGTM, only optical comments.

https://codereview.appspot.com/14746044/diff/3001/provider/maas/storage_test.go
File provider/maas/storage_test.go (right):

https://codereview.appspot.com/14746044/diff/3001/provider/maas/storage_test....
provider/maas/storage_test.go:401: func (s *storageSuite)
TestprefixWithPrivateNamespacePrefixesWithAgentName(c *gc.C) {
Testprefix... instead of TestPrefix...?

https://codereview.appspot.com/14746044/diff/3001/provider/maas/storage_test....
provider/maas/storage_test.go:412: func (s *storageSuite)
TesttprefixWithPrivateNamespaceIgnoresAgentName(c *gc.C) {
Ditto.

[rvb, 2013-10-16 14:07:47]

On 2013/10/16 13:42:08, rog wrote:
> Please take a look.

LGTM