neutron-fwaas/neutron/notifiers/nova.py
Carl Baldwin 3be1d7a75c Replace loopingcall in notifier with a delayed send
The loopingcall thread here was started before processes fork and so
the thread stops working after the fork call.  This is a problem that
will probably need to be worked out in the long run.

To ensure that this notifier works correctly in all processes, this
change replaces the persistent loopingcall thread with a thread
created on demand to delay and batch up notifications.  The first
notification will trigger spawning the thread to wait to send it.  Any
notifications that come in the meantime will notice that there is
already a thread waiting to send and will return without spawning.

Change-Id: I519d4e89b8cee341c0e1cfffbce3e77151e8202a
Closes-Bug: #1301035
2014-04-22 16:22:02 +00:00

251 lines
9.6 KiB
Python

# Copyright (c) 2014 OpenStack Foundation.
# All Rights Reserved.
#
# 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 eventlet
from novaclient import exceptions as nova_exceptions
import novaclient.v1_1.client as nclient
from novaclient.v1_1.contrib import server_external_events
from oslo.config import cfg
from sqlalchemy.orm import attributes as sql_attr
from neutron.common import constants
from neutron import context
from neutron import manager
from neutron.openstack.common import log as logging
from neutron.openstack.common import uuidutils
LOG = logging.getLogger(__name__)
VIF_UNPLUGGED = 'network-vif-unplugged'
VIF_PLUGGED = 'network-vif-plugged'
NEUTRON_NOVA_EVENT_STATUS_MAP = {constants.PORT_STATUS_ACTIVE: 'completed',
constants.PORT_STATUS_ERROR: 'failed',
constants.PORT_STATUS_DOWN: 'completed'}
class Notifier(object):
def __init__(self):
# TODO(arosen): we need to cache the endpoints and figure out
# how to deal with different regions here....
bypass_url = "%s/%s" % (cfg.CONF.nova_url,
cfg.CONF.nova_admin_tenant_id)
self.nclient = nclient.Client(
username=cfg.CONF.nova_admin_username,
api_key=cfg.CONF.nova_admin_password,
project_id=None,
tenant_id=cfg.CONF.nova_admin_tenant_id,
auth_url=cfg.CONF.nova_admin_auth_url,
cacert=cfg.CONF.nova_ca_certificates_file,
insecure=cfg.CONF.nova_api_insecure,
bypass_url=bypass_url,
region_name=cfg.CONF.nova_region_name,
extensions=[server_external_events])
self.pending_events = []
self._waiting_to_send = False
def queue_event(self, event):
"""Called to queue sending an event with the next batch of events.
Sending events individually, as they occur, has been problematic as it
can result in a flood of sends. Previously, there was a loopingcall
thread that would send batched events on a periodic interval. However,
maintaining a persistent thread in the loopingcall was also
problematic.
This replaces the loopingcall with a mechanism that creates a
short-lived thread on demand when the first event is queued. That
thread will sleep once for the same send_events_interval to allow other
events to queue up in pending_events and then will send them when it
wakes.
If a thread is already alive and waiting, this call will simply queue
the event and return leaving it up to the thread to send it.
:param event: the event that occured.
"""
if not event:
return
self.pending_events.append(event)
if self._waiting_to_send:
return
self._waiting_to_send = True
def last_out_sends():
eventlet.sleep(cfg.CONF.send_events_interval)
self._waiting_to_send = False
self.send_events()
eventlet.spawn_n(last_out_sends)
def _is_compute_port(self, port):
try:
if (port['device_id'] and uuidutils.is_uuid_like(port['device_id'])
and port['device_owner'].startswith('compute:')):
return True
except (KeyError, AttributeError):
pass
return False
def _get_network_changed_event(self, device_id):
return {'name': 'network-changed',
'server_uuid': device_id}
@property
def _plugin(self):
# NOTE(arosen): this cannot be set in __init__ currently since
# this class is initalized at the same time as NeutronManager()
# which is decorated with synchronized()
if not hasattr(self, '_plugin_ref'):
self._plugin_ref = manager.NeutronManager.get_plugin()
return self._plugin_ref
def send_network_change(self, action, original_obj,
returned_obj):
"""Called when a network change is made that nova cares about.
:param action: the event that occured.
:param original_obj: the previous value of resource before action.
:param returned_obj: the body returned to client as result of action.
"""
if not cfg.CONF.notify_nova_on_port_data_changes:
return
event = self.create_port_changed_event(action, original_obj,
returned_obj)
self.queue_event(event)
def create_port_changed_event(self, action, original_obj, returned_obj):
port = None
if action == 'update_port':
port = returned_obj['port']
elif action in ['update_floatingip', 'create_floatingip',
'delete_floatingip']:
# NOTE(arosen) if we are associating a floatingip the
# port_id is in the returned_obj. Otherwise on disassociate
# it's in the original_object
port_id = (returned_obj['floatingip'].get('port_id') or
original_obj.get('port_id'))
if port_id is None:
return
ctx = context.get_admin_context()
port = self._plugin.get_port(ctx, port_id)
if port and self._is_compute_port(port):
return self._get_network_changed_event(port['device_id'])
def record_port_status_changed(self, port, current_port_status,
previous_port_status, initiator):
"""Determine if nova needs to be notified due to port status change.
"""
# clear out previous _notify_event
port._notify_event = None
# If there is no device_id set there is nothing we can do here.
if not port.device_id:
LOG.debug(_("device_id is not set on port yet."))
return
if not port.id:
LOG.warning(_("Port ID not set! Nova will not be notified of "
"port status change."))
return
# We only want to notify about nova ports.
if not self._is_compute_port(port):
return
# We notify nova when a vif is unplugged which only occurs when
# the status goes from ACTIVE to DOWN.
if (previous_port_status == constants.PORT_STATUS_ACTIVE and
current_port_status == constants.PORT_STATUS_DOWN):
event_name = VIF_UNPLUGGED
# We only notify nova when a vif is plugged which only occurs
# when the status goes from:
# NO_VALUE/DOWN/BUILD -> ACTIVE/ERROR.
elif (previous_port_status in [sql_attr.NO_VALUE,
constants.PORT_STATUS_DOWN,
constants.PORT_STATUS_BUILD]
and current_port_status in [constants.PORT_STATUS_ACTIVE,
constants.PORT_STATUS_ERROR]):
event_name = VIF_PLUGGED
# All the remaining state transitions are of no interest to nova
else:
LOG.debug(_("Ignoring state change previous_port_status: "
"%(pre_status)s current_port_status: %(cur_status)s"
" port_id %(id)s") %
{'pre_status': previous_port_status,
'cur_status': current_port_status,
'id': port.id})
return
port._notify_event = (
{'server_uuid': port.device_id,
'name': event_name,
'status': NEUTRON_NOVA_EVENT_STATUS_MAP.get(current_port_status),
'tag': port.id})
def send_port_status(self, mapper, connection, port):
event = getattr(port, "_notify_event", None)
self.queue_event(event)
port._notify_event = None
def send_events(self):
batched_events = []
for event in range(len(self.pending_events)):
batched_events.append(self.pending_events.pop())
if not batched_events:
return
LOG.debug(_("Sending events: %s"), batched_events)
try:
response = self.nclient.server_external_events.create(
batched_events)
except nova_exceptions.NotFound:
LOG.warning(_("Nova returned NotFound for event: %s"),
batched_events)
except Exception:
LOG.exception(_("Failed to notify nova on events: %s"),
batched_events)
else:
if not isinstance(response, list):
LOG.error(_("Error response returned from nova: %s"),
response)
return
response_error = False
for event in response:
try:
code = event['code']
except KeyError:
response_error = True
continue
if code != 200:
LOG.warning(_("Nova event: %s returned with failed "
"status"), event)
else:
LOG.info(_("Nova event response: %s"), event)
if response_error:
LOG.error(_("Error response returned from nova: %s"),
response)