Restore juju status compatibility with 1.16

Restore juju status compatibility with 1.16

A stub 'Status' api call was included in 1.16 though not used
in our codebase. It does break the fallback logic to switch
and operate on state directly when talking to a 1.16 state
server however. This branch reintroduces the old call with
the existing name, and uses 'FullStatus' for actual status
api.

https://code.launchpad.net/~gz/juju-core/status_api_1.16_compat/+merge/207482

(do not edit description out of merge proposal)

[gz, 2014-02-20 16:04:46]

Please take a look.

[dimitern, 2014-02-20 16:14:01]

Looks like a good start.

Tests usually go in apiserver/client/, and in this case perhaps it should be in
status_test.go. Look how similar calls are tested. There are also api/client
tests to verify end-to-end integration.

https://codereview.appspot.com/66590043/diff/1/state/api/client.go
File state/api/client.go (right):

https://codereview.appspot.com/66590043/diff/1/state/api/client.go#newcode86
state/api/client.go:86: // LegacyMachineStatus holds just the instance-id of a
machine.
// Remove this in 1.20 or something?
(in all three doc comments below)

https://codereview.appspot.com/66590043/diff/1/state/api/client.go#newcode98
state/api/client.go:98: var s LegacyStatus
s/s/result/ - it's more often called like this in other calls.

https://codereview.appspot.com/66590043/diff/1/state/apiserver/client/status.go
File state/apiserver/client/status.go (right):

https://codereview.appspot.com/66590043/diff/1/state/apiserver/client/status....
state/apiserver/client/status.go:25: func (c *Client) Status()
(api.LegacyStatus, error) {
Shouldn't we keep the params.StatusParams argument?

[gz, 2014-02-20 16:18:53]

Thanks Dimiter!

https://codereview.appspot.com/66590043/diff/1/state/api/client.go
File state/api/client.go (right):

https://codereview.appspot.com/66590043/diff/1/state/api/client.go#newcode86
state/api/client.go:86: // LegacyMachineStatus holds just the instance-id of a
machine.
On 2014/02/20 16:14:01, dimitern wrote:
> // Remove this in 1.20 or something?
> (in all three doc comments below)

Good idea. Can we actually remove it in 1.20 though? Don't we need api
versioning to incompatibily change the api at all?

https://codereview.appspot.com/66590043/diff/1/state/api/client.go#newcode98
state/api/client.go:98: var s LegacyStatus
On 2014/02/20 16:14:01, dimitern wrote:
> s/s/result/ - it's more often called like this in other calls.

Heh, this is actually how it was originally written, but I agree naming it
result (here and above) is clearer.

https://codereview.appspot.com/66590043/diff/1/state/apiserver/client/status.go
File state/apiserver/client/status.go (right):

https://codereview.appspot.com/66590043/diff/1/state/apiserver/client/status....
state/apiserver/client/status.go:25: func (c *Client) Status()
(api.LegacyStatus, error) {
On 2014/02/20 16:14:01, dimitern wrote:
> Shouldn't we keep the params.StatusParams argument?

This is where a longer-range diff would be useful. This method is reproducing
the old 1.16 status api method exactly, which didn't take arguments and didn't
return anything of much use. However, I'm readding it for compat reasons.

[gz, 2014-02-20 16:54:50]

Please take a look.

[dimitern, 2014-02-20 17:11:01]

Better, thanks.

Now you only need to add some api/client tests I think and should be good to
land.

https://codereview.appspot.com/66590043/diff/20001/state/apiserver/client/sta...
File state/apiserver/client/status_test.go (right):

https://codereview.appspot.com/66590043/diff/20001/state/apiserver/client/sta...
state/apiserver/client/status_test.go:29: // XXX: Have to test via the client
even though this is in apiserver,
This is fine and not unusual (other tests use the client as well), so remove
this comment :)

[gz, 2014-02-24 17:44:52]

Please take a look.

[dimitern, 2014-02-24 17:45:53]

On 2014/02/20 17:11:01, dimitern wrote:
> Better, thanks.
> 
> Now you only need to add some api/client tests I think and should be good to
> land.
> 

Forget about this, sorry. I was thinking of the agent api client tests. LGTM.