8a644c1166
The notification listener doesn't have anything to send to the notifier and the notifier doesn't attend to receive something. So this patch remove the message reply when the listener is a notification listener. Partial implements blueprint notification-subscriber-server Change-Id: Ic989947ba3b6894cde788422842fca19159ea261
104 lines
3.7 KiB
Python
104 lines
3.7 KiB
Python
# Copyright 2011 OpenStack Foundation.
|
|
# All Rights Reserved.
|
|
# Copyright 2013 eNovance
|
|
#
|
|
# 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.
|
|
|
|
import contextlib
|
|
import itertools
|
|
import logging
|
|
import sys
|
|
|
|
from oslo.messaging import localcontext
|
|
from oslo.messaging import serializer as msg_serializer
|
|
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
PRIORITIES = ['audit', 'debug', 'info', 'warn', 'error', 'critical', 'sample']
|
|
|
|
|
|
class NotificationDispatcher(object):
|
|
"""A message dispatcher which understands Notification messages.
|
|
|
|
A MessageHandlingServer is constructed by passing a callable dispatcher
|
|
which is invoked with context and message dictionaries each time a message
|
|
is received.
|
|
|
|
NotifcationDispatcher is one such dispatcher which pass a raw notification
|
|
message to the endpoints
|
|
"""
|
|
|
|
def __init__(self, targets, endpoints, serializer):
|
|
self.targets = targets
|
|
self.endpoints = endpoints
|
|
self.serializer = serializer or msg_serializer.NoOpSerializer()
|
|
|
|
self._callbacks_by_priority = {}
|
|
for endpoint, prio in itertools.product(endpoints, PRIORITIES):
|
|
if hasattr(endpoint, prio):
|
|
method = getattr(endpoint, prio)
|
|
self._callbacks_by_priority.setdefault(prio, []).append(method)
|
|
|
|
priorities = self._callbacks_by_priority.keys()
|
|
self._targets_priorities = set(itertools.product(self.targets,
|
|
priorities))
|
|
|
|
def _listen(self, transport):
|
|
return transport._listen_for_notifications(self._targets_priorities)
|
|
|
|
@contextlib.contextmanager
|
|
def __call__(self, incoming):
|
|
yield lambda: self._dispatch_and_handle_error(incoming)
|
|
|
|
def _dispatch_and_handle_error(self, incoming):
|
|
"""Dispatch a notification message to the appropriate endpoint method.
|
|
|
|
:param incoming: the incoming notification message
|
|
:type ctxt: IncomingMessage
|
|
"""
|
|
try:
|
|
self._dispatch(incoming.ctxt, incoming.message)
|
|
except Exception:
|
|
# sys.exc_info() is deleted by LOG.exception().
|
|
exc_info = sys.exc_info()
|
|
LOG.error('Exception during message handling',
|
|
exc_info=exc_info)
|
|
|
|
def _dispatch(self, ctxt, message):
|
|
"""Dispatch an RPC message to the appropriate endpoint method.
|
|
|
|
:param ctxt: the request context
|
|
:type ctxt: dict
|
|
:param message: the message payload
|
|
:type message: dict
|
|
"""
|
|
ctxt = self.serializer.deserialize_context(ctxt)
|
|
|
|
publisher_id = message.get('publisher_id')
|
|
event_type = message.get('event_type')
|
|
priority = message.get('priority', '').lower()
|
|
if priority not in PRIORITIES:
|
|
LOG.warning('Unknown priority "%s"' % priority)
|
|
return
|
|
|
|
payload = self.serializer.deserialize_entity(ctxt,
|
|
message.get('payload'))
|
|
|
|
for callback in self._callbacks_by_priority.get(priority, []):
|
|
localcontext.set_local_context(ctxt)
|
|
try:
|
|
callback(ctxt, publisher_id, event_type, payload)
|
|
finally:
|
|
localcontext.clear_local_context()
|