nova/nova/baserpc.py
Mark McLoughlin 33b9e6f47c Port all rpcapi modules to oslo.messaging interface
Add a temporary nova.rpcclient.RPCClient helper class which translates
oslo.messaging.rpc.RPCClient compatible calls into calls on a RpcProxy
object.

Use this new class to port all of the rpcapi modules over to the new
RPCClient so that the final port of Nova over to oslo.messaging will be
smaller and easier to review.

This patch contains no functional changes at all, except that all client
side RPCs go through this temporary helper class.

blueprint: oslo-messaging
Change-Id: Iee86c36bcc474a604993618b8a2255af8c3d2f48
2013-09-03 21:22:43 +01:00

94 lines
2.9 KiB
Python

#
# Copyright 2013 Red Hat, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
#
"""
Base RPC client and server common to all services.
"""
from oslo.config import cfg
from nova.openstack.common import jsonutils
from nova import rpcclient
CONF = cfg.CONF
rpcapi_cap_opt = cfg.StrOpt('baseapi',
help='Set a version cap for messages sent to the base api in any '
'service')
CONF.register_opt(rpcapi_cap_opt, 'upgrade_levels')
_NAMESPACE = 'baseapi'
class BaseAPI(rpcclient.RpcProxy):
"""Client side of the base rpc API.
API version history:
1.0 - Initial version.
1.1 - Add get_backdoor_port
"""
#
# NOTE(russellb): This is the default minimum version that the server
# (manager) side must implement unless otherwise specified using a version
# argument to self.call()/cast()/etc. here. It should be left as X.0 where
# X is the current major API version (1.0, 2.0, ...). For more information
# about rpc API versioning, see the docs in
# openstack/common/rpc/dispatcher.py.
#
BASE_RPC_API_VERSION = '1.0'
VERSION_ALIASES = {
# baseapi was added in havana
}
def __init__(self, topic):
version_cap = self.VERSION_ALIASES.get(CONF.upgrade_levels.baseapi,
CONF.upgrade_levels.baseapi)
super(BaseAPI, self).__init__(topic=topic,
default_version=self.BASE_RPC_API_VERSION,
version_cap=version_cap)
self.client = self.get_client(namespace=_NAMESPACE)
def ping(self, context, arg, timeout=None):
arg_p = jsonutils.to_primitive(arg)
cctxt = self.client.prepare(timeout=timeout)
return cctxt.call(context, 'ping', arg=arg_p)
def get_backdoor_port(self, context, host):
cctxt = self.client.prepare(server=host, version='1.1')
return cctxt.call(context, 'get_backdoor_port')
class BaseRPCAPI(object):
"""Server side of the base RPC API."""
RPC_API_NAMESPACE = _NAMESPACE
RPC_API_VERSION = '1.1'
def __init__(self, service_name, backdoor_port):
self.service_name = service_name
self.backdoor_port = backdoor_port
def ping(self, context, arg):
resp = {'service': self.service_name, 'arg': arg}
return jsonutils.to_primitive(resp)
def get_backdoor_port(self, context):
return self.backdoor_port