compute rpcapi 2.37 is not backwards compatible

[Joe Gordon]

patch 552693e4ad51291c8bfd28cd1939ed3609f6eeac (https://review.openstack.org/#/c/37933/) which added compute rpcapi version 2.37 does not provide any backwards compatibility, this should be done using 'self.can_send_version'

The result of this is, if compute is running grizzly and trunk is running with

[upgrade_levels]
compute=grizzly

in nova.conf

nova-scheduler logs:

2013-08-26 18:03:17.298 ERROR nova.scheduler.driver [req-a2699da5-38eb-44a4-a314-1c4ff2970e80 demo demo] Exception during scheduler.run_instance
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver Traceback (most recent call last):
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver File "/opt/stack/nova/nova/scheduler/filter_scheduler.py", line 117, in schedule_run_instance
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver legacy_bdm_in_spec=legacy_bdm_in_spec)
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver File "/opt/stack/nova/nova/scheduler/filter_scheduler.py", line 200, in _provision_resource
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver legacy_bdm_in_spec=legacy_bdm_in_spec)
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver File "/opt/stack/nova/nova/compute/rpcapi.py", line 603, in run_instance
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver version='2.37')
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver File "/opt/stack/nova/nova/openstack/common/rpc/proxy.py", line 169, in cast
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver self._set_version(msg, version)
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver File "/opt/stack/nova/nova/openstack/common/rpc/proxy.py", line 72, in _set_version
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver raise rpc_common.RpcVersionCapError(version_cap=self.version_cap)
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver RpcVersionCapError: Specified RPC version cap, 2.27, is too low
2013-08-26 18:03:17.298 2923 TRACE nova.scheduler.driver
2013-08-26 18:03:17.302 WARNING nova.scheduler.driver [req-a2699da5-38eb-44a4-a314-1c4ff2970e80 demo demo] [instance: 3da2957a-0161-4677-ac02-4a74993f15f5] Setting instance to ERROR state.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/43840

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/43840
Committed: http://github.com/openstack/nova/commit/e01e0a269d9a1b7d3d3743f836b78f03b177fedb
Submitter: Jenkins
Branch: master

commit e01e0a269d9a1b7d3d3743f836b78f03b177fedb
Author: Jay Lau <email address hidden>
Date: Tue Aug 27 15:46:26 2013 +0800

    compute rpcapi 2.37 is not backwards compatible

    Patch 552693e4ad51291c8bfd28cd1939ed3609f6eeac which added compute
    rpcapi version 2.37 does not provide any backwards compatibility.

    Fix the issue by 'self.can_send_version'.

    Fix bug 1217044

    Change-Id: I65154fa6298133721b6509b00b117d7f6cc455b8