Merge lp:~hazmat/pyjuju/provider-determines-placement into lp:pyjuju

[Kapil Thangavelu]

Machine providers need to define placement policy

Some provider only support particular placement policies, local
development in particular only supports the local placement policy.
This branch defers policy selection to the provider with input
of the user placement selection and defaulting if none provided
to the environment placement, and if finally to unassigned.

[lp:~hazmat/pyjuju/provider-determines-placement]

380. By Kapil Thangavelu on 2011-09-20

fix test typo

381. By Kapil Thangavelu on 2011-09-20

Merged local-unit-deploy into provider-determines-placement.

382. By Kapil Thangavelu on 2011-09-21

Merged local-unit-deploy into provider-determines-placement.

383. By Kapil Thangavelu on 2011-09-21

Merged local-unit-deploy into provider-determines-placement.

384. By Kapil Thangavelu on 2011-09-21

Merged local-unit-deploy into provider-determines-placement.

385. By Kapil Thangavelu on 2011-09-21

merge pipeline and resolve conflict

386. By Kapil Thangavelu on 2011-09-21

Merged local-unit-deploy into provider-determines-placement.

387. By Kapil Thangavelu on 2011-09-21

Merged local-unit-deploy into provider-determines-placement.

388. By Kapil Thangavelu on 2011-09-22

Merged local-unit-deploy into provider-determines-placement.

[Gustavo Niemeyer (niemeyer)]

Looks good, with one detail:

[1]

183 + def get_placement_policy(self, preference):
184 + """Get the unit placement policy for the provider.
185 +
186 + :param preference: A user specified plcaement policy preference
187 + """
188 + if preference:
189 + return preference

The argument there is pretty weird. If there's a preference that overrules the
provider choice entirely, why calling the provider at all? Let's just drop the
argument and do the usual "if preference is None:" at the call sites.

review: Approve

[Kapil Thangavelu (hazmat)]

Excerpts from Gustavo Niemeyer's message of Fri Sep 23 14:36:38 UTC 2011:
> Review: Approve
>
> Looks good, with one detail:
>
> [1]
>
> 183 + def get_placement_policy(self, preference):
> 184 + """Get the unit placement policy for the provider.
> 185 +
> 186 + :param preference: A user specified plcaement policy preference
> 187 + """
> 188 + if preference:
> 189 + return preference
>
> The argument there is pretty weird. If there's a preference that overrules the
> provider choice entirely, why calling the provider at all? Let's just drop the
> argument and do the usual "if preference is None:" at the call sites.

The whole point of the inversion, is that the provider has the ultimate choice
as to the placement.

The user can express a preference via the cli or config, but not all providers
support all placement policies. ie. the local provider only works with the local
policy, where as providers like ec2 can utilize whichever preference the user
has selected.

Also delegation of policy choice to the environment config is done by the
this method, the passed preference here is just the cli value.

-kapil

[lp:~hazmat/pyjuju/provider-determines-placement]

389. By Kapil Thangavelu on 2011-09-23

Merged local-unit-deploy into provider-determines-placement.

390. By Kapil Thangavelu on 2011-09-23

merge machine-with-type and resolve conflict

391. By Kapil Thangavelu on 2011-09-24

Merged local-unit-deploy into provider-determines-placement.

392. By Kapil Thangavelu on 2011-09-24

add an error for invalid placement policies

393. By Kapil Thangavelu on 2011-09-24

add provider type to error message

394. By Kapil Thangavelu on 2011-09-24

more descriptive error messages in pick, use a generic in place unit

395. By Kapil Thangavelu on 2011-09-24

redo placement policies, providers define which policies they support the cli interaction picks, intersecting with user preference

396. By Kapil Thangavelu on 2011-09-25

Merged local-unit-deploy into provider-determines-placement.

397. By Kapil Thangavelu on 2011-09-27

revert pick_policy, provider determines placement

398. By Kapil Thangavelu on 2011-09-27

yank placement cli parameter per gustavo's suggestion.

399. By Kapil Thangavelu on 2011-09-27

raise a providererror if the environment placement policy is not supported by the local provider