enforce constraints on "neutron router-interface-add"

[Mathieu Rohon]

the bgpvpn spec explicitly mention that :

"To avoid any ambiguity on semantics in particular the context of processing associated to a Router (e.g. NAT or FWaaS), if a said Subnet in a Network is bound to a Router, this API does not allow to both associate the Network to an L3 BGPVPN and the Router to the same or to a distinct L3 BGPVPN."

http://docs.openstack.org/developer/networking-bgpvpn/api.html#association-constraints

But currently this constraint is not enforced since a user can :

-create a net+subnet
-associate this net to a first bgpvpn
-create a router
-associate the router to a second bgpvpn
-attach the subnet to the router

the last action should return an error.

[Mathieu Rohon (mathieu-rohon)]

Since this bug [1] is fixed now in mitaka, the straightforward solution seems to add an new event in ML2 so that the bgpvpn plugin will be notified of a port_update that reflects the attachment of a port to a router.

If both the router and the network of the port are already attached to a bgpvpn, we should send an exception that will prevent the attachment of that network to the router.

[1]https://bugs.launchpad.net/bgpvpn/+bug/1475093

[Mathieu Rohon (mathieu-rohon)]

related rfe on neutron :

https://bugs.launchpad.net/neutron/+bug/1537091

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/369413

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/369413
Committed: https://git.openstack.org/cgit/openstack/networking-bgpvpn/commit/?id=9a3c45b80e2f8ea26a1879a0e7a3856ab5ca2784
Submitter: Jenkins
Branch: master

commit 9a3c45b80e2f8ea26a1879a0e7a3856ab5ca2784
Author: Mathieu Rohon <email address hidden>
Date: Tue Sep 13 11:18:06 2016 +0000

    Prevent mixing bgpvpn associations

    As mentioned in the spec, a router and one of its subnet
    cannot be both attached to a bgpvpn.
    This patch enforce this rule by adding a check when a subnet is
    attached to a router.

    Co-Authored-By: Wim De Clercq <email address hidden>
    Change-Id: Ie1f6a733e8a16b8b41e89c5a82637d7cb03bd423
    Closes-bug: #1537067

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/networking-bgpvpn 5.0.0 release.