Quota Management of Dynamic resources in Nested Projects

Quota Management is an interestring topic and efficient resource allocation and quota management of resources is at the heart of any private/hybrid/public Openstack deployments. With the adoption of Hierarchical Multi-tenancy in Keystone [1] other projects in Openstack need to make changes to there Quota Management layer to take the benefits of Hierarchical multi-tenancy. Nova has already started an effort [2]. But [2] only manages quota for static resources. But with the growing requirement from Openstack users on the need for Quota by flavor, Quota by AZ, Quota by X; the design proposed in [2] will not be good enough to handle that. [3] proposed the idea to introduce the concept of "Dynamic quota resource" but that is limited to flat hierarchy. This work plans to enhance [2] further to handle quota for both static and dynamic resources.

As part of this work the concepts of Quota by Flavor, Quota by AZ, Quota by X in general will be added to so that the Quota management is hierarchy agnostic (works for both hierarchical and non-hierarchical setup) and is resource aware ( both static and dynamic resource).

So the proposition is to hierarchy agnostic and resource aware Quota Management

[1] http://specs.openstack.org/openstack/keystone-specs/specs/juno/hierarchical_multitenancy.html
[2] https://blueprints.launchpad.net/nova/+spec/nested-quota-driver-api
[3] https://review.openstack.org/#/c/206160/