Updated information should be shown after attaching/detaching volume operation against instance

[David Jia]

Updated information can be shown after instance rename, reboot and son on, but when attach/detach a volume to virtual server, cannot get the updated virtual server info.

The operation step:
1) Get the last updated time '2013-12-09T08:23:40Z' of vs.
2) Attach a volume to vs.
3) Use the following url and get the updated virtual server.
The request url: /v2/8501b77195204880bebc6bb4806c43aa/servers/detail?changes-since=2013-12-09T08:23:40Z
The resp body:
<?xml version='1.0' encoding='UTF-8'?>
<servers xmlns:os-extended-volumes="http://docs.openstack.org/compute/ext/extended_volumes/api/v1.1" xmlns:OS-EXT-IPS="http://docs.openstack.org/compute/ext/extended_ips/api/v1.1" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:OS-DCF="http://docs.openstack.org/compute/ext/disk_config/api/v1.1" xmlns:OS-EXT-IPS-MAC="http://docs.openstack.org/compute/ext/extended_ips_mac/api/v1.1" xmlns:OS-EXT-SRV-ATTR="http://docs.openstack.org/compute/ext/extended_status/api/v1.1" xmlns:OS-SRV-USG="http://docs.openstack.org/compute/ext/server_usage/api/v1.1" xmlns:OS-EXT-STS="http://docs.openstack.org/compute/ext/extended_status/api/v1.1" xmlns:OS-EXT-AZ="http://docs.openstack.org/compute/ext/extended_availability_zone/api/v2" xmlns="http://docs.openstack.org/compute/api/v1.1"/>

I cannot see the updated virtual server in resp body. I checked the table instances and found the 'updated_at' field is not modified after attaching a volume to vs, but it is modified after rename/reboot an instance.Here I think it should get the updated vs info because it indeed change the virtual server when attaching an volume.

[Matt Riedemann (mriedem)]

There are already a few bugs for this same issue, so tracking under a single bug.