d986a6f280
- adds simple chance scheduling on create pool operation - adds PoolsLoadbalancerAgentBinding db table - adds lbaas_agentscheduler extension to list pools hosted by a particular agent and to get an agent hosting a particular pool - adds agent notifiers mapping to AgentSchedulerDbMixin to make it easier for services to add their agent notifiers to the core plugin Implements blueprint lbaas-agent-scheduler Change-Id: Id98649fd5c7873dcd5be1a2b117b8bed25f06cc2
115 lines
4.4 KiB
Python
115 lines
4.4 KiB
Python
# vim: tabstop=4 shiftwidth=4 softtabstop=4
|
|
|
|
# Copyright (c) 2013 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 random
|
|
|
|
import sqlalchemy as sa
|
|
from sqlalchemy import orm
|
|
from sqlalchemy.orm import joinedload
|
|
|
|
from neutron.common import constants
|
|
from neutron.db import agents_db
|
|
from neutron.db import agentschedulers_db
|
|
from neutron.db import model_base
|
|
from neutron.extensions import lbaas_agentscheduler
|
|
from neutron.openstack.common import log as logging
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
|
|
class PoolLoadbalancerAgentBinding(model_base.BASEV2):
|
|
"""Represents binding between neutron loadbalancer pools and agents."""
|
|
|
|
pool_id = sa.Column(sa.String(36),
|
|
sa.ForeignKey("pools.id", ondelete='CASCADE'),
|
|
primary_key=True)
|
|
agent = orm.relation(agents_db.Agent)
|
|
agent_id = sa.Column(sa.String(36), sa.ForeignKey("agents.id",
|
|
ondelete='CASCADE'))
|
|
|
|
|
|
class LbaasAgentSchedulerDbMixin(agentschedulers_db.AgentSchedulerDbMixin,
|
|
lbaas_agentscheduler
|
|
.LbaasAgentSchedulerPluginBase):
|
|
|
|
def get_lbaas_agent_hosting_pool(self, context, pool_id, active=None):
|
|
query = context.session.query(PoolLoadbalancerAgentBinding)
|
|
query = query.options(joinedload('agent'))
|
|
binding = query.get(pool_id)
|
|
|
|
if (binding and self.is_eligible_agent(
|
|
active, binding.agent)):
|
|
return {'agent': self._make_agent_dict(binding.agent)}
|
|
|
|
def get_lbaas_agents(self, context, active=None, filters=None):
|
|
query = context.session.query(agents_db.Agent)
|
|
query = query.filter_by(agent_type=constants.AGENT_TYPE_LOADBALANCER)
|
|
if active is not None:
|
|
query = query.filter_by(admin_state_up=active)
|
|
if filters:
|
|
for key, value in filters.iteritems():
|
|
column = getattr(agents_db.Agent, key, None)
|
|
if column:
|
|
query = query.filter(column.in_(value))
|
|
|
|
return [agent
|
|
for agent in query
|
|
if self.is_eligible_agent(active, agent)]
|
|
|
|
def list_pools_on_lbaas_agent(self, context, id):
|
|
query = context.session.query(PoolLoadbalancerAgentBinding.pool_id)
|
|
query = query.filter_by(agent_id=id)
|
|
pool_ids = [item[0] for item in query]
|
|
if pool_ids:
|
|
return {'pools': self.get_pools(context, filters={'id': pool_ids})}
|
|
else:
|
|
return {'pools': []}
|
|
|
|
|
|
class ChanceScheduler(object):
|
|
"""Allocate a loadbalancer agent for a vip in a random way."""
|
|
|
|
def schedule(self, plugin, context, pool):
|
|
"""Schedule the pool to an active loadbalancer agent if there
|
|
is no enabled agent hosting it.
|
|
"""
|
|
with context.session.begin(subtransactions=True):
|
|
lbaas_agent = plugin.get_lbaas_agent_hosting_pool(
|
|
context, pool['id'])
|
|
if lbaas_agent:
|
|
LOG.debug(_('Pool %(pool_id)s has already been hosted'
|
|
' by lbaas agent %(agent_id)s'),
|
|
{'pool_id': pool['id'],
|
|
'agent_id': lbaas_agent['id']})
|
|
return
|
|
|
|
candidates = plugin.get_lbaas_agents(context, active=True)
|
|
if not candidates:
|
|
LOG.warn(_('No active lbaas agents for pool %s') % pool['id'])
|
|
return
|
|
|
|
chosen_agent = random.choice(candidates)
|
|
binding = PoolLoadbalancerAgentBinding()
|
|
binding.agent = chosen_agent
|
|
binding.pool_id = pool['id']
|
|
context.session.add(binding)
|
|
LOG.debug(_('Pool %(pool_id)s is scheduled to '
|
|
'lbaas agent %(agent_id)s'),
|
|
{'pool_id': pool['id'],
|
|
'agent_id': chosen_agent['id']})
|
|
return chosen_agent
|