HA: upgrade upstart and initiate replset

HA: upgrade upstart and initiate replset

The machine agent will now upgrade the
Mongo upstart script and initiate the
replicaset when upgrading from a version
prior to 1.19.0.

Tested upgrading 1.18.1 to 1.19.1 with and
without HA enabled; tested straight bootstrap
to 1.19.1 with and without HA enabled.

https://code.launchpad.net/~axwalk/juju-core/lp1306902-ha-upgrade/+merge/215999

(do not edit description out of merge proposal)

[axw, 2014-04-16 04:14:59]

Please take a look.

[rog, 2014-04-16 10:15:03]

Looks great in general, modulo a few minor suggestions below. I'd like to take a
look after tip has merged into this branch.

https://codereview.appspot.com/88350043/diff/1/agent/mongo/mongo.go
File agent/mongo/mongo.go (right):

https://codereview.appspot.com/88350043/diff/1/agent/mongo/mongo.go#newcode202
agent/mongo/mongo.go:202: if service.Running() {
I don't think this condition is necessary - Service.Stop checks whether the
service is running as a matter of course.

https://codereview.appspot.com/88350043/diff/1/cmd/jujud/machine.go
File cmd/jujud/machine.go (right):

https://codereview.appspot.com/88350043/diff/1/cmd/jujud/machine.go#newcode433
cmd/jujud/machine.go:433: // shouldEnableHA returns whether HA should be
enabled.
s/returns/reports/

(standard phrasing)

https://codereview.appspot.com/88350043/diff/1/cmd/jujud/machine.go#newcode452
cmd/jujud/machine.go:452: withHA := shouldEnableHA(agentConfig)
perhaps factor out lines 447 to 504 into a separate function,
say MachineAgent.ensureMongoServer(agentConfig agent.Config) error

?

[axw, 2014-04-16 23:59:56]

https://codereview.appspot.com/88350043/diff/1/agent/mongo/mongo.go
File agent/mongo/mongo.go (right):

https://codereview.appspot.com/88350043/diff/1/agent/mongo/mongo.go#newcode202
agent/mongo/mongo.go:202: if service.Running() {
On 2014/04/16 10:15:04, rog wrote:
> I don't think this condition is necessary - Service.Stop checks whether the
> service is running as a matter of course.

Thanks, I was assuming the same behaviour as "service stop".

https://codereview.appspot.com/88350043/diff/1/cmd/jujud/machine.go
File cmd/jujud/machine.go (right):

https://codereview.appspot.com/88350043/diff/1/cmd/jujud/machine.go#newcode433
cmd/jujud/machine.go:433: // shouldEnableHA returns whether HA should be
enabled.
On 2014/04/16 10:15:04, rog wrote:
> s/returns/reports/
> 
> (standard phrasing)

Done.

https://codereview.appspot.com/88350043/diff/1/cmd/jujud/machine.go#newcode452
cmd/jujud/machine.go:452: withHA := shouldEnableHA(agentConfig)
On 2014/04/16 10:15:04, rog wrote:
> perhaps factor out lines 447 to 504 into a separate function,
> say MachineAgent.ensureMongoServer(agentConfig agent.Config) error
> 
> ?

Done.