EnsureMongoServer function for MachineAgent

EnsureMongoServer function for MachineAgent

Implement a method to allow the machine agent to create & run the upstart script for mongo.

https://code.launchpad.net/~natefinch/juju-core/026-EnsureMongoServer/+merge/201961

(do not edit description out of merge proposal)

[rog, 2014-01-16 17:01:11]

Looks good so far, with a couple of suggestions/queries below.

https://codereview.appspot.com/53220043/diff/20001/agent/agent.go
File agent/agent.go (right):

https://codereview.appspot.com/53220043/diff/20001/agent/agent.go#newcode232
agent/agent.go:232: func MongoDbDir(dir string) string {
or this could be a method on Config.

at the least, dir should be named "dataDir"

https://codereview.appspot.com/53220043/diff/20001/cmd/jujud/machine.go
File cmd/jujud/machine.go (right):

https://codereview.appspot.com/53220043/diff/20001/cmd/jujud/machine.go#newco...
cmd/jujud/machine.go:386: if err := conf.Install(); err != nil {
Do we really want to do this every time the machine agent bounces?
If possible I'd prefer to avoid bouncing mongod in that case.

https://codereview.appspot.com/53220043/diff/20001/replicaset/replicaset.go
File replicaset/replicaset.go (right):

https://codereview.appspot.com/53220043/diff/20001/replicaset/replicaset.go#n...
replicaset/replicaset.go:257: State MemberState `bson:"State"`
"state", surely?

[natefinch, 2014-01-16 21:39:14]

Some more clean up, and now add the "ensure" part of ensure mongo server.  Also
consolidated the code so we only do this in machine agent.

Also, just ignore the stuff in replicaset.go, it's not really part of this
change and I'll remove it.

[natefinch, 2014-01-17 10:56:42]

Please take a look.

[fwereade, 2014-01-22 10:46:38]

couple of quick comments, I think I may have misunderstood the StatePort bits,
can we chat when you're free?

https://codereview.appspot.com/53220043/diff/60001/agent/agent.go
File agent/agent.go (right):

https://codereview.appspot.com/53220043/diff/60001/agent/agent.go#newcode99
agent/agent.go:99: StatePort() int
I'm a bit bothered about storing this in agent config. And actually about
storing *any* of this stuff in agent config -- we have manual bootstrap now, and
I don't see why this is needed any more.

https://codereview.appspot.com/53220043/diff/60001/provider/local/environ.go
File provider/local/environ.go (right):

https://codereview.appspot.com/53220043/diff/60001/provider/local/environ.go#...
provider/local/environ.go:427: journalDir := filepath.Join(env.config.rootDir(),
"db/journal")
"db", "journal"?

https://codereview.appspot.com/53220043/diff/60001/upstart/service.go
File upstart/service.go (right):

https://codereview.appspot.com/53220043/diff/60001/upstart/service.go#newcode26
upstart/service.go:26: func MongoUpstartService(name, dataDir string, port int)
*Conf {
Hmm, I'm really not sure this is the right package for this file. Isn't this
stuff all specific to instance config?