Open Stack

On Thu, 2012-07-19 at 14:20 +0100, Mark McLoughlin wrote:
> Hi,
> 
> I was just reviewing the code for this:
> 
>   https://blueprints.launchpad.net/nova/+spec/os-api-network-create
> 
> You POST to /networks:
> 
>   {"network": {"vlan_start": 234, "cidr": "10.70.105.0/24", "label": "net234"}}
> 
> and get back e.g.
> 
>   {"networks": [{..., "id": 66085e78-8f6-4a26-b16c-4b1f55901fbd", ..., "label": "net234", ..., "vlan": 234, ..., "cidr": "10.70.105.0/24", ...}]}
> 
> Notice the plural "networks" in the response. A single POST may create
> multiple networks (where e.g. FLAGS.num_networks > 1), but it's not
> clear to me what the use case for this is.
> 
> The issue with this is that (at least IMHO) POST requests should only
> create a single resource - e.g. we want to be able to return a 201
> Created response with a Location header and it would seem bizarre to
> include multiple location headers.

For anyone interested, this debate is still rumbling on here:

  https://review.openstack.org/#/c/9847/

I've tried to be pretty clear about my objection to the proposed
modelling:

  REST stands for Representational State Transfer

  When you POST to /networks, you are sending a representation of the
  network resource you want to create

  The sensible thing for a client to expect is that a network resource
  will be created and for a 201 Created response to include a
  representation the resource and a Location header with a URI for the
  resource

  What doesn't seem at all sensible is for the server to return a
  collection of resources, based on "num_networks" and "network_size"
  properties in the network representation and also based on the server
  configuration

Other opinions are most welcome, though.

Cheers,
Mark.