Skip the service-label dance in Azure.

Skip the service-label dance in Azure.

We're still working out how we're supposed to determine an instance's DNS name
in Azure.  We may have been chasing a red herring early on: on the one hand
the documentation hinted that a service's name also formed the hostname part
of its DNS name, but on the other, we were getting what looked like a randomly
generated DNS name assigned by Azure.  And a little dance was orchestrated
around that: get the instance URL from the Deployment object, store it in the
Service's label field, use the label field as the source of the DNS name.

As we understand it now, the weird randomly assigned hostnames only happen in
Staging deployments, and the instance URLs don't even resolve when we deploy
to Production (as we must do in Juju).

And so this branch does away with the little dance, uses the service name as
the instance's DNS name, and rips out all code that I could find that was only
there to support the dance.  The service label is now a mere courtesy; it's
required but we may as well set it to be identical to the service name.

https://code.launchpad.net/~jtv/juju-core/az-use-production-dns-name/+merge/174906

(do not edit description out of merge proposal)

[jtv.canonical, 2013-07-16 03:24:56]

Please take a look.

[rvb, 2013-07-16 09:28:42]

LGTM (I've successfully tested this IRL with the change I mention in [1]).

[0]

21	+	// This provider always deploys to Production.  Think twice about
22	+	// changing that: we're still not quite sure how DNS names in the
23	+	// staging slot are supposed to work.  There's a "deployment URL"

We know pretty well how this works now: in "Production", the Service's
ServiceName is the DNS name and the "deployment URL" contains a
randomly-generated hostname which does not resolve.  In "Staging", the Service's
ServiceName is *not* the DNS name and the "deployment URL" contains a
randomly-generated hostname which *does* resolve.

[1]

As discussed, we need to fix environprovider.go:getDeploymentFQDN() to reflect
the changes made by this branch. (It needs to return fmt.Sprintf("%s.%s",
config.getDeploymentName(), AZURE_DOMAIN_NAME))

[jtv.canonical, 2013-07-16 10:23:24]

Please take a look.

[mue, 2013-07-16 10:58:47]

LGTM

[rog, 2013-07-16 11:06:29]

LGTM superficially, assuming staging doesn't
have important properties that people may miss
later.

https://codereview.appspot.com/11322043/diff/5001/environs/azure/environ.go
File environs/azure/environ.go (right):

https://codereview.appspot.com/11322043/diff/5001/environs/azure/environ.go#n...
environs/azure/environ.go:34: // The deployment slot where to deploy instances. 
Azure supports
minor gripe: we usually phrase doc comments as full sentences,
even for constants and variables:

// DeploymentSlot holds the name of the slot that
// instances will be deployed to.

?

any particular reason it's exported?

[jtv.canonical, 2013-07-16 11:25:14]

On 2013/07/16 11:06:29, rog wrote:
> LGTM superficially, assuming staging doesn't
> have important properties that people may miss
> later.

Mostly it has the important property that it makes it much harder to get a
working DNS name.  Even if people miss that, Juju doesn't support doing anything
about it!


>
https://codereview.appspot.com/11322043/diff/5001/environs/azure/environ.go#n...
> environs/azure/environ.go:34: // The deployment slot where to deploy
instances. 
> Azure supports
> minor gripe: we usually phrase doc comments as full sentences,
> even for constants and variables:
> 
> // DeploymentSlot holds the name of the slot that
> // instances will be deployed to.

Fixed.


> any particular reason it's exported?

Nope.  Good one — I just un-exported it.