'binding:host_id' is set None when port update without portbinding changes

[Hyunsun Moon]

When I try to update port for additional fixed IP or any other attributes other than portbinding, _process_portbindings_create_and_update is set 'None' in port update messages sent to the agents in spite of it has host_id.
It may not be a problem if the agents do not use portbinding information but if the agent uses 'binding:host_id' information for port update it will cause a problem, which is in my case.

When look at the codes, Neutron server sets 'binding:host_id' to 'None' as long as 'binding:host_id' is not in the requested update items. It should query DB to set correct port binding instead of 'None' in that case.

[Eugene Nikanorov (enikanorov)]

I could not reproduce this issue with port update.
Can you specify the list of commands I need to run to reproduce?

What plugin do you use?

[Hyunsun Moon (hyunsun-moon)]

It is linuxbrige plugin.
I tested with the following command.

# neutron port-update XXXXX --fixed_ips type=dict list=true ip_address=10.0.0.3,ip_address=10.0.0.4

I'm using cutomized code for dhcp-agent, which checks binding host ID when port update event occurs.
It's originally from "https://review.openstack.org/#/c/24771/"

---------------------------------------------------------------------------------------
    def port_update_end(self, context, payload):
        """Handle the port.update.end notification event."""
        port = DictModel(payload['port'])
        network = self.cache.get_network_by_id(port.network_id)
        if network:
            device_owner = port.device_owner
            if (self.conf.enable_multi_host and device_owner
                and device_owner.startswith('compute:') and
                self.host != getattr(port, 'binding:host_id', None)): <<<< HERE
                self._unlocked_port_delete_end(context,
                                               {'port_id': port.id})
                return
            self.cache.put_port(port)
            self.call_driver('reload_allocations', network)
---------------------------------------------------------------------------------------

Port update message from the server includes "None" for 'binding:host_id' as I added debug there, and that makes the above logic fails(it only perform action if the binding:host_id is the same with the hostname of itself).
It of course no issue with the original Neutron because it doesn't use 'binding:host_id' in the agents but could be a potential issue later.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/62829
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=9b083d7636508cbc5addfe3457c1aac706f0e267
Submitter: Jenkins
Branch: master

commit 9b083d7636508cbc5addfe3457c1aac706f0e267
Author: hyunsun <email address hidden>
Date: Wed Dec 18 18:03:34 2013 +0900

    Fix binding:host_id is set to None when port update

    when updating a port 'binding:host_id' is reset if not specified among
    the parameter to be updated. As a result, a None value for
    'binding:host_id' is sent from the notifier which might potentially
    cause consumers to not work properly.

    Closes-Bug: #1245310
    Change-Id: Icfb5179940cca9f8a705eb36bdbfcbc8a421a272