neutron-dynamic-routing/neutron_dynamic_routing/db/bgp_dragentscheduler_db.py
Boden R 155f66337c use context manager from neutron-lib
Access to neutron.db.api's context manager is already in neutron-lib
and in fact neutron is already using it as a shim. This patch switches
over context manager access to use neutron-lib's accessors.
Also see https://review.openstack.org/#/c/613122

Change-Id: Id07fb7da50f80a3434c6bf790ffddf2bb25a6796
2018-12-03 13:29:08 -07:00

277 lines
12 KiB
Python

# Copyright 2016 Huawei Technologies India Pvt. Ltd.
# 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.
from neutron_lib import context as ncontext
from neutron_lib.db import api as db_api
from neutron_lib.db import model_base
from oslo_config import cfg
from oslo_db import exception as db_exc
from oslo_log import log as logging
import sqlalchemy as sa
from sqlalchemy import orm
from sqlalchemy.orm import exc
from neutron.db import agentschedulers_db as as_db
from neutron.db.models import agent as agent_model
from neutron_dynamic_routing._i18n import _
from neutron_dynamic_routing._i18n import _LW
from neutron_dynamic_routing.extensions import bgp_dragentscheduler as bgp_dras_ext # noqa
from neutron_dynamic_routing.services.bgp.common import constants as bgp_consts
LOG = logging.getLogger(__name__)
BGP_DRAGENT_SCHEDULER_OPTS = [
cfg.StrOpt(
'bgp_drscheduler_driver',
default='neutron_dynamic_routing.services.bgp.scheduler'
'.bgp_dragent_scheduler.ChanceScheduler',
help=_('Driver used for scheduling BGP speakers to BGP DrAgent'))
]
cfg.CONF.register_opts(BGP_DRAGENT_SCHEDULER_OPTS)
class BgpSpeakerDrAgentBinding(model_base.BASEV2):
"""Represents a mapping between BGP speaker and BGP DRAgent"""
__tablename__ = 'bgp_speaker_dragent_bindings'
bgp_speaker_id = sa.Column(sa.String(length=36),
sa.ForeignKey("bgp_speakers.id",
ondelete='CASCADE'),
nullable=False)
dragent = orm.relation(agent_model.Agent)
agent_id = sa.Column(sa.String(length=36),
sa.ForeignKey("agents.id",
ondelete='CASCADE'),
primary_key=True)
class BgpDrAgentSchedulerDbMixin(bgp_dras_ext.BgpDrSchedulerPluginBase,
as_db.AgentSchedulerDbMixin):
bgp_drscheduler = None
def add_periodic_dragent_status_check(self):
if self.bgp_drscheduler:
self.add_agent_status_check_worker(
self.remove_bgp_speaker_from_down_dragents)
self.add_agent_status_check_worker(
self.schedule_all_unscheduled_bgp_speakers)
else:
LOG.warning(_LW("Cannot schedule BgpSpeaker to DrAgent. "
"Reason: No scheduler registered."))
def schedule_all_unscheduled_bgp_speakers(self):
context = ncontext.get_admin_context()
if self.bgp_drscheduler:
return self.bgp_drscheduler.schedule_all_unscheduled_bgp_speakers(
context)
else:
LOG.warning(_LW("Cannot schedule BgpSpeaker to DrAgent. "
"Reason: No scheduler registered."))
def schedule_unscheduled_bgp_speakers(self, context, host):
if self.bgp_drscheduler:
return self.bgp_drscheduler.schedule_unscheduled_bgp_speakers(
context, host)
else:
LOG.warning(_LW("Cannot schedule BgpSpeaker to DrAgent. "
"Reason: No scheduler registered."))
def schedule_bgp_speaker(self, context, created_bgp_speaker):
if self.bgp_drscheduler:
agents = self.bgp_drscheduler.schedule(self, context,
created_bgp_speaker)
for agent in agents:
self._bgp_rpc.bgp_speaker_created(context,
created_bgp_speaker['id'],
agent.host)
else:
LOG.warning(_LW("Cannot schedule BgpSpeaker to DrAgent. "
"Reason: No scheduler registered."))
def add_bgp_speaker_to_dragent(self, context, agent_id, speaker_id):
"""Associate a BgpDrAgent with a BgpSpeaker."""
try:
self._save_bgp_speaker_dragent_binding(context,
agent_id,
speaker_id)
except db_exc.DBDuplicateEntry:
raise bgp_dras_ext.DrAgentAssociationError(
agent_id=agent_id)
LOG.debug('BgpSpeaker %(bgp_speaker_id)s added to '
'BgpDrAgent %(agent_id)s',
{'bgp_speaker_id': speaker_id, 'agent_id': agent_id})
def _save_bgp_speaker_dragent_binding(self, context,
agent_id, speaker_id):
with db_api.CONTEXT_WRITER.using(context):
agent_db = self._get_agent(context, agent_id)
agent_up = agent_db['admin_state_up']
is_agent_bgp = (agent_db['agent_type'] ==
bgp_consts.AGENT_TYPE_BGP_ROUTING)
if not is_agent_bgp or not agent_up:
raise bgp_dras_ext.DrAgentInvalid(id=agent_id)
binding = BgpSpeakerDrAgentBinding()
binding.bgp_speaker_id = speaker_id
binding.agent_id = agent_id
context.session.add(binding)
self._bgp_rpc.bgp_speaker_created(context, speaker_id, agent_db.host)
def remove_bgp_speaker_from_down_dragents(self):
self.reschedule_resources_from_down_agents(
agent_type=bgp_consts.AGENT_TYPE_BGP_ROUTING,
get_down_bindings=self.get_down_bgp_speaker_bindings,
agent_id_attr='agent_id',
resource_id_attr='bgp_speaker_id',
resource_name='bgp_speaker',
reschedule_resource=self.reschedule_bgp_speaker,
rescheduling_failed=bgp_dras_ext.BgpSpeakerRescheduleError)
def get_down_bgp_speaker_bindings(self, context, agent_dead_limit):
cutoff = self.get_cutoff_time(agent_dead_limit)
query = (
context.session.query(BgpSpeakerDrAgentBinding).
join(agent_model.Agent).
filter(agent_model.Agent.heartbeat_timestamp < cutoff,
agent_model.Agent.admin_state_up))
down_bindings = [b for b in query]
return down_bindings
def reschedule_bgp_speaker(self, context, bgp_speaker_id):
dragent = self.get_dragents_hosting_bgp_speakers(
context, [bgp_speaker_id])[0]
bgp_speaker = self.get_bgp_speaker(context, bgp_speaker_id)
dragent_id = dragent.id
with db_api.CONTEXT_WRITER.using(context):
self._remove_bgp_speaker_from_dragent(
context, dragent_id, bgp_speaker_id)
self.schedule_bgp_speaker(context, bgp_speaker)
new_dragents = self.get_dragents_hosting_bgp_speakers(
context, [bgp_speaker_id])
if new_dragents == [] or new_dragents[0].id == dragent.id:
raise bgp_dras_ext.BgpSpeakerRescheduleError(
bgp_speaker_id=bgp_speaker_id,
failure_reason="no eligible dr agent found")
def _remove_bgp_speaker_from_dragent(self, context, agent_id, speaker_id):
with db_api.CONTEXT_WRITER.using(context):
agent_db = self._get_agent(context, agent_id)
is_agent_bgp = (agent_db['agent_type'] ==
bgp_consts.AGENT_TYPE_BGP_ROUTING)
if not is_agent_bgp:
raise bgp_dras_ext.DrAgentInvalid(id=agent_id)
query = context.session.query(BgpSpeakerDrAgentBinding)
query = query.filter_by(bgp_speaker_id=speaker_id,
agent_id=agent_id)
num_deleted = query.delete()
if not num_deleted:
raise bgp_dras_ext.DrAgentNotHostingBgpSpeaker(
bgp_speaker_id=speaker_id,
agent_id=agent_id)
LOG.debug('BgpSpeaker %(bgp_speaker_id)s removed from '
'BgpDrAgent %(agent_id)s',
{'bgp_speaker_id': speaker_id,
'agent_id': agent_id})
def remove_bgp_speaker_from_dragent(self, context, agent_id, speaker_id):
self._remove_bgp_speaker_from_dragent(context, agent_id, speaker_id)
agent_db = self._get_agent(context, agent_id)
self._bgp_rpc.bgp_speaker_removed(context, speaker_id, agent_db.host)
def get_dragents_hosting_bgp_speakers(self, context, bgp_speaker_ids,
active=None, admin_state_up=None):
query = context.session.query(BgpSpeakerDrAgentBinding)
query = query.options(orm.contains_eager(
BgpSpeakerDrAgentBinding.dragent))
query = query.join(BgpSpeakerDrAgentBinding.dragent)
if len(bgp_speaker_ids) == 1:
query = query.filter(
BgpSpeakerDrAgentBinding.bgp_speaker_id == (
bgp_speaker_ids[0]))
elif bgp_speaker_ids:
query = query.filter(
BgpSpeakerDrAgentBinding.bgp_speaker_id in bgp_speaker_ids)
if admin_state_up is not None:
query = query.filter(agent_model.Agent.admin_state_up ==
admin_state_up)
return [binding.dragent
for binding in query
if as_db.AgentSchedulerDbMixin.is_eligible_agent(
active, binding.dragent)]
def get_dragent_bgp_speaker_bindings(self, context):
return context.session.query(BgpSpeakerDrAgentBinding).all()
def list_dragent_hosting_bgp_speaker(self, context, speaker_id):
dragents = self.get_dragents_hosting_bgp_speakers(context,
[speaker_id])
agent_ids = [dragent.id for dragent in dragents]
if not agent_ids:
return {'agents': []}
return {'agents': self.get_agents(context, filters={'id': agent_ids})}
def list_bgp_speaker_on_dragent(self, context, agent_id):
query = context.session.query(BgpSpeakerDrAgentBinding.bgp_speaker_id)
query = query.filter_by(agent_id=agent_id)
bgp_speaker_ids = [item[0] for item in query]
if not bgp_speaker_ids:
# Exception will be thrown if the requested agent does not exist.
self._get_agent(context, agent_id)
return {'bgp_speakers': []}
return {'bgp_speakers':
self.get_bgp_speakers(context,
filters={'id': bgp_speaker_ids})}
def get_bgp_speakers_for_agent_host(self, context, host):
agent = self._get_agent_by_type_and_host(
context, bgp_consts.AGENT_TYPE_BGP_ROUTING, host)
if not agent.admin_state_up:
return {}
query = context.session.query(BgpSpeakerDrAgentBinding)
query = query.filter(BgpSpeakerDrAgentBinding.agent_id == agent.id)
try:
binding = query.one()
except exc.NoResultFound:
return []
bgp_speaker = self.get_bgp_speaker_with_advertised_routes(
context, binding['bgp_speaker_id'])
return [bgp_speaker]
def get_bgp_speaker_by_speaker_id(self, context, bgp_speaker_id):
try:
return self.get_bgp_speaker(context, bgp_speaker_id)
except exc.NoResultFound:
return {}
def get_bgp_peer_by_peer_id(self, context, bgp_peer_id):
try:
return self.get_bgp_peer(context, bgp_peer_id)
except exc.NoResultFound:
return {}