cmd/juju: support upgrade-charm --force

cmd/juju: support upgrade-charm --force

This adds support for the --force flag to
upgrade-charm command, also needed for
parity with py-juju.

https://code.launchpad.net/~dimitern/juju-core/018-upgrade-charm-force-flag/+merge/155774

(do not edit description out of merge proposal)

[dimitern, 2013-03-27 15:49:15]

Please take a look.

[fwereade, 2013-03-27 15:56:29]

LGTM if you're happy with the doc suggestions.

https://codereview.appspot.com/7838054/diff/1/cmd/juju/ssh.go
File cmd/juju/ssh.go (right):

https://codereview.appspot.com/7838054/diff/1/cmd/juju/ssh.go#newcode81
cmd/juju/ssh.go:81: log.Infof("cmd/juju: looking up address for unit %q...",
c.Target)
good catch, thank you

https://codereview.appspot.com/7838054/diff/1/cmd/juju/upgradecharm.go
File cmd/juju/upgradecharm.go (right):

https://codereview.appspot.com/7838054/diff/1/cmd/juju/upgradecharm.go#newcode38
cmd/juju/upgradecharm.go:38: to understand the risks and be able to deal with
potential problems.
Use of the --force flag is not generally recommended; units upgraded while in an
error state will not have upgrade-charm hooks executed, and may thus behave
surprisingly.

?

https://codereview.appspot.com/7838054/diff/1/cmd/juju/upgradecharm.go#newcode52
cmd/juju/upgradecharm.go:52: f.BoolVar(&c.Force, "force", false, "force an
upgrade, regardless of unit state; no hooks executed")
Not quite accurate; only error units will skip hooks.

"upgrade all units immediately, even if in error state"

?

https://codereview.appspot.com/7838054/diff/1/cmd/juju/upgradecharm.go#newcod...
cmd/juju/upgradecharm.go:111: log.Warningf("cmd/juju: forcing upgrade of service
%q to charm %q", sch.URL(), service.Name())
I don't think we really need to tell the user what they just explicitly did.

[dimitern, 2013-03-27 16:21:59]

Please take a look.

https://codereview.appspot.com/7838054/diff/1/cmd/juju/ssh.go
File cmd/juju/ssh.go (right):

https://codereview.appspot.com/7838054/diff/1/cmd/juju/ssh.go#newcode81
cmd/juju/ssh.go:81: log.Infof("cmd/juju: looking up address for unit %q...",
c.Target)
On 2013/03/27 15:56:29, fwereade wrote:
> good catch, thank you

cheers, I wouldn't have noticed if I haven't just finished jam's review of
sync-tools, where this is commonplace with log messages.

https://codereview.appspot.com/7838054/diff/1/cmd/juju/upgradecharm.go
File cmd/juju/upgradecharm.go (right):

https://codereview.appspot.com/7838054/diff/1/cmd/juju/upgradecharm.go#newcode38
cmd/juju/upgradecharm.go:38: to understand the risks and be able to deal with
potential problems.
On 2013/03/27 15:56:29, fwereade wrote:
> Use of the --force flag is not generally recommended; units upgraded while in
an
> error state will not have upgrade-charm hooks executed, and may thus behave
> surprisingly.
> 
> ?

Done, except (as discussed s/surprisingly/unexpectedly/).

https://codereview.appspot.com/7838054/diff/1/cmd/juju/upgradecharm.go#newcode52
cmd/juju/upgradecharm.go:52: f.BoolVar(&c.Force, "force", false, "force an
upgrade, regardless of unit state; no hooks executed")
On 2013/03/27 15:56:29, fwereade wrote:
> Not quite accurate; only error units will skip hooks.
> 
> "upgrade all units immediately, even if in error state"
> 
> ?

I took this from py-juju, but I agree this is better.

https://codereview.appspot.com/7838054/diff/1/cmd/juju/upgradecharm.go#newcod...
cmd/juju/upgradecharm.go:111: log.Warningf("cmd/juju: forcing upgrade of service
%q to charm %q", sch.URL(), service.Name())
On 2013/03/27 15:56:29, fwereade wrote:
> I don't think we really need to tell the user what they just explicitly did.

Done.

[fwereade, 2013-03-27 17:06:30]

Still LGTM, just a last suggestion

https://codereview.appspot.com/7838054/diff/5001/cmd/juju/upgradecharm.go
File cmd/juju/upgradecharm.go (right):

https://codereview.appspot.com/7838054/diff/5001/cmd/juju/upgradecharm.go#new...
cmd/juju/upgradecharm.go:36: an error state will not have upgrade-charm hooks
executed, and may thus behave
on reflection, I'd most like "and may cause unexpected behavior".

[dimitern, 2013-03-27 17:47:55]

Please take a look.

https://codereview.appspot.com/7838054/diff/5001/cmd/juju/upgradecharm.go
File cmd/juju/upgradecharm.go (right):

https://codereview.appspot.com/7838054/diff/5001/cmd/juju/upgradecharm.go#new...
cmd/juju/upgradecharm.go:36: an error state will not have upgrade-charm hooks
executed, and may thus behave
On 2013/03/27 17:06:30, fwereade wrote:
> on reflection, I'd most like "and may cause unexpected behavior".

Done.

[rog, 2013-03-27 17:50:06]

LGTM

[dimitern, 2013-03-27 18:17:01]

*** Submitted:

cmd/juju: support upgrade-charm --force

This adds support for the --force flag to
upgrade-charm command, also needed for
parity with py-juju.

R=fwereade, rog
CC=
https://codereview.appspot.com/7838054