Move dns related data field out of ml2 plugin into dns plugin

[bin Yu]

Now, We prefer to enable DNS support in Neutron by enabling the extension_drivers in Neutron plugin configurations. However, we still have the dns related data in ml2 core plugin like dns_name in ports data fields.

We prefer to remove the code section like "if ('dns-integration' in self.supported_extension_aliases and 'dns_name' in p)" out of db_base_plugin_v2.py

and code like
   if "dns_name" in port:
             res["dns_name"] = port["dns_name"]
out of db_base_plugin_common.py.

The goal is to let the dns plugin handle the dns request, and the core plugin calling the dns plugin through the method like extension_drivers and app_dict. we hope to hide the detail of dns information from the prespective of core plugin.

[Ryan Moats (rmoats)]

armax, this reads more like an RFE to me, so I have tagged it as such.

[Armando Migliaccio (armando-migliaccio)]

This is code refactoring. Miguel Lavalle should be able to provide more input.

[Armando Migliaccio (armando-migliaccio)]

https://review.openstack.org/#/c/313291/

I don't quite see why we need the data migration though.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/313291
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=64f5fc82596ec6b78b76ca5d9cfc1d4b5a0b975d
Submitter: Jenkins
Branch: master

commit 64f5fc82596ec6b78b76ca5d9cfc1d4b5a0b975d
Author: Bin Yu <email address hidden>
Date: Fri May 6 17:20:04 2016 +0800

    Refactor DNS integration out of DB core plugin

    This patch set aims to move all the code related to DNS integration
    from the DB core plugin to the DNS ML2 extension module.

    By doing this, this patchset removes the dns related code in
    db_base_plugin_v2 and the dns exteions module talks with core plugin
    only through the method extension_manager and apply_dict_extend_functions

    By properly implementing the generation of the dns_assignment attribute
    for ports in the DNS ML2 extension module, this patchset also fixes
    https://bugs.launchpad.net/neutron/+bug/1579977

    Change-Id: I63afb1a1bfeeb14eefb54681dc64959144deeb25
    Closes-Bug: #1579601
    Closes-Bug: #1579977

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 9.0.0.0b3 development milestone.