afb0b7b141
Because the openstack common project does not stick to latest pep8 rules, I have to exclude some bad-ruled files in the tox.ini and run_tests.sh. However pep8 does not support exclude option in the format quantum/openstack/common, so I have to exclude some of openstack common files one by one. Also, I have changed the Qunatum Context to base on the common context. I does not update the setup.py in our openstack common dir and the one under quantum top dir, since it should be maintained in a consistent way across all of openstack projects. After this introduction, we are ready for notification feature. Change-Id: I2729c2dc3958835374c88d704e842e613785ec14
419 lines
15 KiB
Python
419 lines
15 KiB
Python
# vim: tabstop=4 shiftwidth=4 softtabstop=4
|
|
|
|
# Copyright 2010 United States Government as represented by the
|
|
# Administrator of the National Aeronautics and Space Administration.
|
|
# All Rights Reserved.
|
|
# Copyright 2011 - 2012, 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.
|
|
|
|
"""
|
|
Shared code between AMQP based openstack.common.rpc implementations.
|
|
|
|
The code in this module is shared between the rpc implemenations based on AMQP.
|
|
Specifically, this includes impl_kombu and impl_qpid. impl_carrot also uses
|
|
AMQP, but is deprecated and predates this code.
|
|
"""
|
|
|
|
import inspect
|
|
import logging
|
|
import sys
|
|
import uuid
|
|
|
|
from eventlet import greenpool
|
|
from eventlet import pools
|
|
from eventlet import semaphore
|
|
|
|
from quantum.openstack.common import excutils
|
|
from quantum.openstack.common.gettextutils import _
|
|
from quantum.openstack.common import local
|
|
from quantum.openstack.common.rpc import common as rpc_common
|
|
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
|
|
class Pool(pools.Pool):
|
|
"""Class that implements a Pool of Connections."""
|
|
def __init__(self, conf, connection_cls, *args, **kwargs):
|
|
self.connection_cls = connection_cls
|
|
self.conf = conf
|
|
kwargs.setdefault("max_size", self.conf.rpc_conn_pool_size)
|
|
kwargs.setdefault("order_as_stack", True)
|
|
super(Pool, self).__init__(*args, **kwargs)
|
|
|
|
# TODO(comstud): Timeout connections not used in a while
|
|
def create(self):
|
|
LOG.debug('Pool creating new connection')
|
|
return self.connection_cls(self.conf)
|
|
|
|
def empty(self):
|
|
while self.free_items:
|
|
self.get().close()
|
|
|
|
|
|
_pool_create_sem = semaphore.Semaphore()
|
|
|
|
|
|
def get_connection_pool(conf, connection_cls):
|
|
with _pool_create_sem:
|
|
# Make sure only one thread tries to create the connection pool.
|
|
if not connection_cls.pool:
|
|
connection_cls.pool = Pool(conf, connection_cls)
|
|
return connection_cls.pool
|
|
|
|
|
|
class ConnectionContext(rpc_common.Connection):
|
|
"""The class that is actually returned to the caller of
|
|
create_connection(). This is essentially a wrapper around
|
|
Connection that supports 'with'. It can also return a new
|
|
Connection, or one from a pool. The function will also catch
|
|
when an instance of this class is to be deleted. With that
|
|
we can return Connections to the pool on exceptions and so
|
|
forth without making the caller be responsible for catching
|
|
them. If possible the function makes sure to return a
|
|
connection to the pool.
|
|
"""
|
|
|
|
def __init__(self, conf, connection_pool, pooled=True, server_params=None):
|
|
"""Create a new connection, or get one from the pool"""
|
|
self.connection = None
|
|
self.conf = conf
|
|
self.connection_pool = connection_pool
|
|
if pooled:
|
|
self.connection = connection_pool.get()
|
|
else:
|
|
self.connection = connection_pool.connection_cls(
|
|
conf,
|
|
server_params=server_params)
|
|
self.pooled = pooled
|
|
|
|
def __enter__(self):
|
|
"""When with ConnectionContext() is used, return self"""
|
|
return self
|
|
|
|
def _done(self):
|
|
"""If the connection came from a pool, clean it up and put it back.
|
|
If it did not come from a pool, close it.
|
|
"""
|
|
if self.connection:
|
|
if self.pooled:
|
|
# Reset the connection so it's ready for the next caller
|
|
# to grab from the pool
|
|
self.connection.reset()
|
|
self.connection_pool.put(self.connection)
|
|
else:
|
|
try:
|
|
self.connection.close()
|
|
except Exception:
|
|
pass
|
|
self.connection = None
|
|
|
|
def __exit__(self, exc_type, exc_value, tb):
|
|
"""End of 'with' statement. We're done here."""
|
|
self._done()
|
|
|
|
def __del__(self):
|
|
"""Caller is done with this connection. Make sure we cleaned up."""
|
|
self._done()
|
|
|
|
def close(self):
|
|
"""Caller is done with this connection."""
|
|
self._done()
|
|
|
|
def create_consumer(self, topic, proxy, fanout=False):
|
|
self.connection.create_consumer(topic, proxy, fanout)
|
|
|
|
def create_worker(self, topic, proxy, pool_name):
|
|
self.connection.create_worker(topic, proxy, pool_name)
|
|
|
|
def consume_in_thread(self):
|
|
self.connection.consume_in_thread()
|
|
|
|
def __getattr__(self, key):
|
|
"""Proxy all other calls to the Connection instance"""
|
|
if self.connection:
|
|
return getattr(self.connection, key)
|
|
else:
|
|
raise rpc_common.InvalidRPCConnectionReuse()
|
|
|
|
|
|
def msg_reply(conf, msg_id, connection_pool, reply=None, failure=None,
|
|
ending=False):
|
|
"""Sends a reply or an error on the channel signified by msg_id.
|
|
|
|
Failure should be a sys.exc_info() tuple.
|
|
|
|
"""
|
|
with ConnectionContext(conf, connection_pool) as conn:
|
|
if failure:
|
|
failure = rpc_common.serialize_remote_exception(failure)
|
|
|
|
try:
|
|
msg = {'result': reply, 'failure': failure}
|
|
except TypeError:
|
|
msg = {'result': dict((k, repr(v))
|
|
for k, v in reply.__dict__.iteritems()),
|
|
'failure': failure}
|
|
if ending:
|
|
msg['ending'] = True
|
|
conn.direct_send(msg_id, msg)
|
|
|
|
|
|
class RpcContext(rpc_common.CommonRpcContext):
|
|
"""Context that supports replying to a rpc.call"""
|
|
def __init__(self, **kwargs):
|
|
self.msg_id = kwargs.pop('msg_id', None)
|
|
self.conf = kwargs.pop('conf')
|
|
super(RpcContext, self).__init__(**kwargs)
|
|
|
|
def deepcopy(self):
|
|
values = self.to_dict()
|
|
values['conf'] = self.conf
|
|
values['msg_id'] = self.msg_id
|
|
return self.__class__(**values)
|
|
|
|
def reply(self, reply=None, failure=None, ending=False,
|
|
connection_pool=None):
|
|
if self.msg_id:
|
|
msg_reply(self.conf, self.msg_id, connection_pool, reply, failure,
|
|
ending)
|
|
if ending:
|
|
self.msg_id = None
|
|
|
|
|
|
def unpack_context(conf, msg):
|
|
"""Unpack context from msg."""
|
|
context_dict = {}
|
|
for key in list(msg.keys()):
|
|
# NOTE(vish): Some versions of python don't like unicode keys
|
|
# in kwargs.
|
|
key = str(key)
|
|
if key.startswith('_context_'):
|
|
value = msg.pop(key)
|
|
context_dict[key[9:]] = value
|
|
context_dict['msg_id'] = msg.pop('_msg_id', None)
|
|
context_dict['conf'] = conf
|
|
ctx = RpcContext.from_dict(context_dict)
|
|
rpc_common._safe_log(LOG.debug, _('unpacked context: %s'), ctx.to_dict())
|
|
return ctx
|
|
|
|
|
|
def pack_context(msg, context):
|
|
"""Pack context into msg.
|
|
|
|
Values for message keys need to be less than 255 chars, so we pull
|
|
context out into a bunch of separate keys. If we want to support
|
|
more arguments in rabbit messages, we may want to do the same
|
|
for args at some point.
|
|
|
|
"""
|
|
context_d = dict([('_context_%s' % key, value)
|
|
for (key, value) in context.to_dict().iteritems()])
|
|
msg.update(context_d)
|
|
|
|
|
|
class ProxyCallback(object):
|
|
"""Calls methods on a proxy object based on method and args."""
|
|
|
|
def __init__(self, conf, proxy, connection_pool):
|
|
self.proxy = proxy
|
|
self.pool = greenpool.GreenPool(conf.rpc_thread_pool_size)
|
|
self.connection_pool = connection_pool
|
|
self.conf = conf
|
|
|
|
def __call__(self, message_data):
|
|
"""Consumer callback to call a method on a proxy object.
|
|
|
|
Parses the message for validity and fires off a thread to call the
|
|
proxy object method.
|
|
|
|
Message data should be a dictionary with two keys:
|
|
method: string representing the method to call
|
|
args: dictionary of arg: value
|
|
|
|
Example: {'method': 'echo', 'args': {'value': 42}}
|
|
|
|
"""
|
|
# It is important to clear the context here, because at this point
|
|
# the previous context is stored in local.store.context
|
|
if hasattr(local.store, 'context'):
|
|
del local.store.context
|
|
rpc_common._safe_log(LOG.debug, _('received %s'), message_data)
|
|
ctxt = unpack_context(self.conf, message_data)
|
|
method = message_data.get('method')
|
|
args = message_data.get('args', {})
|
|
version = message_data.get('version', None)
|
|
if not method:
|
|
LOG.warn(_('no method for message: %s') % message_data)
|
|
ctxt.reply(_('No method for message: %s') % message_data,
|
|
connection_pool=self.connection_pool)
|
|
return
|
|
self.pool.spawn_n(self._process_data, ctxt, version, method, args)
|
|
|
|
def _process_data(self, ctxt, version, method, args):
|
|
"""Process a message in a new thread.
|
|
|
|
If the proxy object we have has a dispatch method
|
|
(see rpc.dispatcher.RpcDispatcher), pass it the version,
|
|
method, and args and let it dispatch as appropriate. If not, use
|
|
the old behavior of magically calling the specified method on the
|
|
proxy we have here.
|
|
"""
|
|
ctxt.update_store()
|
|
try:
|
|
rval = self.proxy.dispatch(ctxt, version, method, **args)
|
|
# Check if the result was a generator
|
|
if inspect.isgenerator(rval):
|
|
for x in rval:
|
|
ctxt.reply(x, None, connection_pool=self.connection_pool)
|
|
else:
|
|
ctxt.reply(rval, None, connection_pool=self.connection_pool)
|
|
# This final None tells multicall that it is done.
|
|
ctxt.reply(ending=True, connection_pool=self.connection_pool)
|
|
except Exception as e:
|
|
LOG.exception('Exception during message handling')
|
|
ctxt.reply(None, sys.exc_info(),
|
|
connection_pool=self.connection_pool)
|
|
|
|
|
|
class MulticallWaiter(object):
|
|
def __init__(self, conf, connection, timeout):
|
|
self._connection = connection
|
|
self._iterator = connection.iterconsume(timeout=timeout or
|
|
conf.rpc_response_timeout)
|
|
self._result = None
|
|
self._done = False
|
|
self._got_ending = False
|
|
self._conf = conf
|
|
|
|
def done(self):
|
|
if self._done:
|
|
return
|
|
self._done = True
|
|
self._iterator.close()
|
|
self._iterator = None
|
|
self._connection.close()
|
|
|
|
def __call__(self, data):
|
|
"""The consume() callback will call this. Store the result."""
|
|
if data['failure']:
|
|
failure = data['failure']
|
|
self._result = rpc_common.deserialize_remote_exception(self._conf,
|
|
failure)
|
|
|
|
elif data.get('ending', False):
|
|
self._got_ending = True
|
|
else:
|
|
self._result = data['result']
|
|
|
|
def __iter__(self):
|
|
"""Return a result until we get a 'None' response from consumer"""
|
|
if self._done:
|
|
raise StopIteration
|
|
while True:
|
|
try:
|
|
self._iterator.next()
|
|
except Exception:
|
|
with excutils.save_and_reraise_exception():
|
|
self.done()
|
|
if self._got_ending:
|
|
self.done()
|
|
raise StopIteration
|
|
result = self._result
|
|
if isinstance(result, Exception):
|
|
self.done()
|
|
raise result
|
|
yield result
|
|
|
|
|
|
def create_connection(conf, new, connection_pool):
|
|
"""Create a connection"""
|
|
return ConnectionContext(conf, connection_pool, pooled=not new)
|
|
|
|
|
|
def multicall(conf, context, topic, msg, timeout, connection_pool):
|
|
"""Make a call that returns multiple times."""
|
|
# Can't use 'with' for multicall, as it returns an iterator
|
|
# that will continue to use the connection. When it's done,
|
|
# connection.close() will get called which will put it back into
|
|
# the pool
|
|
LOG.debug(_('Making asynchronous call on %s ...'), topic)
|
|
msg_id = uuid.uuid4().hex
|
|
msg.update({'_msg_id': msg_id})
|
|
LOG.debug(_('MSG_ID is %s') % (msg_id))
|
|
pack_context(msg, context)
|
|
|
|
conn = ConnectionContext(conf, connection_pool)
|
|
wait_msg = MulticallWaiter(conf, conn, timeout)
|
|
conn.declare_direct_consumer(msg_id, wait_msg)
|
|
conn.topic_send(topic, msg)
|
|
return wait_msg
|
|
|
|
|
|
def call(conf, context, topic, msg, timeout, connection_pool):
|
|
"""Sends a message on a topic and wait for a response."""
|
|
rv = multicall(conf, context, topic, msg, timeout, connection_pool)
|
|
# NOTE(vish): return the last result from the multicall
|
|
rv = list(rv)
|
|
if not rv:
|
|
return
|
|
return rv[-1]
|
|
|
|
|
|
def cast(conf, context, topic, msg, connection_pool):
|
|
"""Sends a message on a topic without waiting for a response."""
|
|
LOG.debug(_('Making asynchronous cast on %s...'), topic)
|
|
pack_context(msg, context)
|
|
with ConnectionContext(conf, connection_pool) as conn:
|
|
conn.topic_send(topic, msg)
|
|
|
|
|
|
def fanout_cast(conf, context, topic, msg, connection_pool):
|
|
"""Sends a message on a fanout exchange without waiting for a response."""
|
|
LOG.debug(_('Making asynchronous fanout cast...'))
|
|
pack_context(msg, context)
|
|
with ConnectionContext(conf, connection_pool) as conn:
|
|
conn.fanout_send(topic, msg)
|
|
|
|
|
|
def cast_to_server(conf, context, server_params, topic, msg, connection_pool):
|
|
"""Sends a message on a topic to a specific server."""
|
|
pack_context(msg, context)
|
|
with ConnectionContext(conf, connection_pool, pooled=False,
|
|
server_params=server_params) as conn:
|
|
conn.topic_send(topic, msg)
|
|
|
|
|
|
def fanout_cast_to_server(conf, context, server_params, topic, msg,
|
|
connection_pool):
|
|
"""Sends a message on a fanout exchange to a specific server."""
|
|
pack_context(msg, context)
|
|
with ConnectionContext(conf, connection_pool, pooled=False,
|
|
server_params=server_params) as conn:
|
|
conn.fanout_send(topic, msg)
|
|
|
|
|
|
def notify(conf, context, topic, msg, connection_pool):
|
|
"""Sends a notification event on a topic."""
|
|
event_type = msg.get('event_type')
|
|
LOG.debug(_('Sending %(event_type)s on %(topic)s'), locals())
|
|
pack_context(msg, context)
|
|
with ConnectionContext(conf, connection_pool) as conn:
|
|
conn.notify_send(topic, msg)
|
|
|
|
|
|
def cleanup(connection_pool):
|
|
if connection_pool:
|
|
connection_pool.empty()
|