Nova API - seems to support only a per AZ endpoint model

[Kavan Patil <ka...@gmail.com>]

Hi All,

I have been testing NovaApi against HP Cloud and have been working with
both per AZ endpoint model and a region wide endpoint model in different
zones.

For clarity I would define the two terms:

Per AZ endpoint model : I call it so as we get a per AZ compute endpoint
url. Using this URL we could only work with a particular AZ of a cloud
provider (e.g. HP Cloud region-a has az1.region-a.geo-1 as one AZ and has
its own compute endpoint)

Region wide endpoint model: I call it so as we have one compute endpoint
for the entire zone. All the openstack services work region wide and
compute instance can be placed on all AZs within the region selectively.
(e.g. HPCloud region-b.geo-1, which will have a single endpoint for compute
for the entire region. This is still in private beta stage.)

The existing framework with JClouds doesn't seem to fit the region wide
model and below I describe 3 issues I see.

So start with I can create a single connection for HP Cloud as below
-----------
NovaApi api =
                ContextBuilder.newBuilder("hpcloud-compute")
                 .credentials(identity, password)
                 .modules(modules)
                 .apiVersion("2") //The api version of region-b.geo-1 is 2
which is required for next steps

-------------

1. But to get a Handle to the ServerApi under this region I need to give
the name of a region!

-------------
//So now we have a new connection to region-b-geo-1

//But to get a ServerApi handle I need to do
//This looks ugly, as i need to provide the name of region for a zone!
serverApi = this.novaApi.getServerApiForZone("region-b.geo-1");

//As the below throws error
serverApi = this.novaApi.getServerApiForZone("az1");
------------------------------

2. Also now that I have a ServerApi to the region, I don't get to select
the an AZ to place a instance as there is no CreateServerOption to specifiy
an AZ name!

3. And the below call should return all AZs (az1, az2, az3), but it only
returns region-b.geo-1
---------------------
this.novaApi.getConfiguredZones()
---------------------

I think this is due to the fact that the implementation of
getConfiguredZones() is mapped to the endpoints in the service catalogue
rather than the below API extension:

----------------
curl -i https://region-b.geo-1.compute.hpcloudsvc.com/v2/<tenant-id>/os-availability-zone
-X GET -H "Accept: application/json" -H "X-Auth-Token: <token>"

RESP: [200] CaseInsensitiveDict({'date': 'Mon, 05 Aug 2013 10:35:03 GMT',
'content-length': '236', 'content-type': 'application/json',
'x-compute-request-id': 'req-c19dcfba-8a21-4a7e-b463-19943267c9bb'})
RESP BODY: {"availabilityZoneInfo": [{"zoneState": {"available": true},
"hosts": null, "zoneName": "az1"}, {"zoneState": {"available": true},
"hosts": null, "zoneName": "az2"}, {"zoneState": {"available": true},
"hosts": null, "zoneName": "az3"}]}
--------------

If people agree I could file a bug on this.

Regards,
Kavan