api(server)/uniter: Return tags instead of names

api(server)/uniter: Return tags instead of names

UniterAPI.SubordinateNames() is renamed to
HasSubordinates() and returns (bool, error).
Added a TODO in uniter/modes.go to use it
instead of calling len(u.unit.SubordinateNames) > 0,
and since the other place SubordinateNames() was
called is now handled by DestroyAllSubordinates()
there's no need for it anymore.
Also GetPrincipal() now returns a unit tag, not
a name.

https://code.launchpad.net/~dimitern/juju-core/114-api-uniter-names-to-tags/+merge/183481

Requires: https://code.launchpad.net/~dimitern/juju-core/113-api-uniter-unit-destroy-fix/+merge/183474

(do not edit description out of merge proposal)

[dimitern, 2013-09-02 14:54:21]

Please take a look.

[fwereade, 2013-09-02 15:30:54]

suggestion as live

https://codereview.appspot.com/13348050/diff/1/state/api/uniter/unit.go
File state/api/uniter/unit.go (right):

https://codereview.appspot.com/13348050/diff/1/state/api/uniter/unit.go#newco...
state/api/uniter/unit.go:251: err := u.st.caller.Call("Uniter", "",
"Subordinates", args, &results)
This can actually just be HasSubordinates, given the usage of SubordindateNames
in uniter

[dimitern, 2013-09-02 15:39:42]

Please take a look.

[fwereade, 2013-09-02 15:42:59]

LGTM with trivials

https://codereview.appspot.com/13348050/diff/5001/state/api/uniter/uniter_tes...
File state/api/uniter/uniter_test.go (right):

https://codereview.appspot.com/13348050/diff/5001/state/api/uniter/uniter_tes...
state/api/uniter/uniter_test.go:268: ok, err := unit.HasSubordinates()
found, err might read better. meh.

https://codereview.appspot.com/13348050/diff/5001/state/apiserver/uniter/unit...
File state/apiserver/uniter/uniter.go (right):

https://codereview.appspot.com/13348050/diff/5001/state/apiserver/uniter/unit...
state/apiserver/uniter/uniter.go:321: func (u *UniterAPI)
unitNamesToTags(unitNames []string) []string {
still used?

[dimitern, 2013-09-02 15:57:49]

Please take a look.

https://codereview.appspot.com/13348050/diff/5001/state/api/uniter/uniter_tes...
File state/api/uniter/uniter_test.go (right):

https://codereview.appspot.com/13348050/diff/5001/state/api/uniter/uniter_tes...
state/api/uniter/uniter_test.go:268: ok, err := unit.HasSubordinates()
On 2013/09/02 15:42:59, fwereade wrote:
> found, err might read better. meh.

Done.

https://codereview.appspot.com/13348050/diff/5001/state/apiserver/uniter/unit...
File state/apiserver/uniter/uniter.go (right):

https://codereview.appspot.com/13348050/diff/5001/state/apiserver/uniter/unit...
state/apiserver/uniter/uniter.go:321: func (u *UniterAPI)
unitNamesToTags(unitNames []string) []string {
On 2013/09/02 15:42:59, fwereade wrote:
> still used?

No, removed, thanks.