make batch API create/delete atomic

I prefer to use an extension to make an API for nova on server side, which will need modify the plugin , so that we can make use of the database's transaction.
At the same time we have to augment the client to use this extension's API. And then most of the nova network API methods are just wrappers to the client's methods.

Yong approach makes sense - we certainly want to leverage DB transaction for the base v2 plugin.
It is also important that the client provides a way for leveraging this API capability - and I will create a related bug report in python-quantumclient for this.

What needs to be discussed and decided is, in my opinion, the following:

- should bulk create/delete part of the core API or an extension?
- do we need a different URI for the requests or can we reuse the existing ones (e.g.: POST /networks with a list of networks in the request body to be created atomically)
- do we want to support bulk updates as well?

It is also my opinion that this fix should concern bulk operations on one kind of resource only. That is to say, we will allow to create a bunch of ports in a single operation, but creating a network with a set of ports and then subnets with allocated IPs in a single operation is certainly out of scope here, and I'm not sure we even want this in the Quantum API.

If the Nova <-> Quantum integration is going to be built on batch operations, I think these operations would have to be part of the core API.

I agree on the need for having bulk operations as part of the core.

It is my opinion that we should not introduce complexity by defining new URIs for bulk operations. POST /<resource> and DELETE /<resource> should be able to handle both single and bulk requests.

Bulk updates are desirable, but they have a lower priority. If we get them "for free" from this bug fix, that would be great.

The Bug report for Quantum client is here: https://bugs.launchpad.net/python-quantumclient/+bug/1021726

I am leaning to consider lack of feedback as a statement from the community that we are happy with not introducing new URIs for bulk operations.

I tend to agree. We have a lot on our plate for F-3, and I'm not convinced this is a strict requirement.

Fix proposed to branch: master
Review: https://review.openstack.org/10732

Reviewed: https://review.openstack.org/10732
Committed: http://github.com/openstack/quantum/commit/ff837025e955799e69eebcab665374436649d6f8
Submitter: Jenkins
Branch: master

commit ff837025e955799e69eebcab665374436649d6f8
Author: Salvatore Orlando <email address hidden>
Date: Mon Aug 13 09:31:38 2012 -0700

    Fix bulk create operations and make them atomic.

    Bug 1024844
    Bug 1020639

    The API layer is now able to issue bulk create requests to the plugin,
    assuming that the plugin supports them. Otherwise, the API layer will
    emulate atomic behavior.
    This patch also implements OVS plugin support for bulk requests.

    Change-Id: I515148d870d0dff8371862fe577c477538364929