vmware-nsx/neutron/services/loadbalancer/plugin.py
Oleg Bondarev bf8949defc LBaaS: unify haproxy-on-host plugin driver and agent
Unifies haproxy reference implementation to make common agent based plugin driver
which is suitable for all vendors who wants to use async mechanism.

 - Agent API as well as device driver API changed to handle
   loadbalancer objects individually;
 - Agent loads device drivers according to config;
 - LogicalDeviceCache class was removed from agent as it was used only
   as a list - to put and remove entries ant check whether entry is in or not.
   It was replaced with instance_mapping dict in agent to store known instances and
   corresponding device_drivers;
 - Agent reports which device drivers are supported (needs for scheduling on plugin side);
 - Agent-to-plugin API was extended to provide an ability for agent to update
   statuses of pools/vips/members/health_monitors;
 - Vendor should only implement device driver; plugin driver just needs
   to inherit AgentBasedPluginDriver and override device_driver member;
 - This patch doesn't move files to make review easier;
   all rename/replace will be done in a subsequent patch;

DocImpact

NOTE: Since the change in the agent RPC API is backward-incompatible
(major RPC version change), LBaaS server-agent communications will be
completely broken until both sides are upgraded so users will be unable to
create new or update existing HAProxy loadbalancer instances during upgrade

Implements blueprint lbaas-common-agent-driver

Change-Id: I9fd90a1321611d202ef838681273081fa6c1686a
2013-12-10 12:08:03 +04:00

319 lines
13 KiB
Python

#
# Copyright 2013 Radware LTD.
#
# 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.
#
# @author: Avishay Balderman, Radware
from neutron.api.v2 import attributes as attrs
from neutron.common import exceptions as n_exc
from neutron import context
from neutron.db import api as qdbapi
from neutron.db.loadbalancer import loadbalancer_db as ldb
from neutron.db import servicetype_db as st_db
from neutron.openstack.common import excutils
from neutron.openstack.common import log as logging
from neutron.plugins.common import constants
from neutron.services.loadbalancer import agent_scheduler
from neutron.services import provider_configuration as pconf
from neutron.services import service_base
LOG = logging.getLogger(__name__)
class LoadBalancerPlugin(ldb.LoadBalancerPluginDb,
agent_scheduler.LbaasAgentSchedulerDbMixin):
"""Implementation of the Neutron Loadbalancer Service Plugin.
This class manages the workflow of LBaaS request/response.
Most DB related works are implemented in class
loadbalancer_db.LoadBalancerPluginDb.
"""
supported_extension_aliases = ["lbaas",
"lbaas_agent_scheduler",
"service-type"]
# lbaas agent notifiers to handle agent update operations;
# can be updated by plugin drivers while loading;
# will be extracted by neutron manager when loading service plugins;
agent_notifiers = {}
def __init__(self):
"""Initialization for the loadbalancer service plugin."""
qdbapi.register_models()
self.service_type_manager = st_db.ServiceTypeManager.get_instance()
self._load_drivers()
def _load_drivers(self):
"""Loads plugin-drivers specified in configuration."""
self.drivers, self.default_provider = service_base.load_drivers(
constants.LOADBALANCER, self)
# we're at the point when extensions are not loaded yet
# so prevent policy from being loaded
ctx = context.get_admin_context(load_admin_roles=False)
# stop service in case provider was removed, but resources were not
self._check_orphan_pool_associations(ctx, self.drivers.keys())
def _check_orphan_pool_associations(self, context, provider_names):
"""Checks remaining associations between pools and providers.
If admin has not undeployed resources with provider that was deleted
from configuration, neutron service is stopped. Admin must delete
resources prior to removing providers from configuration.
"""
pools = self.get_pools(context)
lost_providers = set([pool['provider'] for pool in pools
if pool['provider'] not in provider_names])
# resources are left without provider - stop the service
if lost_providers:
msg = _("Delete associated loadbalancer pools before "
"removing providers %s") % list(lost_providers)
LOG.exception(msg)
raise SystemExit(msg)
def _get_driver_for_provider(self, provider):
if provider in self.drivers:
return self.drivers[provider]
# raise if not associated (should never be reached)
raise n_exc.Invalid(_("Error retrieving driver for provider %s") %
provider)
def _get_driver_for_pool(self, context, pool_id):
pool = self.get_pool(context, pool_id)
try:
return self.drivers[pool['provider']]
except KeyError:
raise n_exc.Invalid(_("Error retrieving provider for pool %s") %
pool_id)
def get_plugin_type(self):
return constants.LOADBALANCER
def get_plugin_description(self):
return "Neutron LoadBalancer Service Plugin"
def create_vip(self, context, vip):
v = super(LoadBalancerPlugin, self).create_vip(context, vip)
driver = self._get_driver_for_pool(context, v['pool_id'])
driver.create_vip(context, v)
return v
def update_vip(self, context, id, vip):
if 'status' not in vip['vip']:
vip['vip']['status'] = constants.PENDING_UPDATE
old_vip = self.get_vip(context, id)
v = super(LoadBalancerPlugin, self).update_vip(context, id, vip)
driver = self._get_driver_for_pool(context, v['pool_id'])
driver.update_vip(context, old_vip, v)
return v
def _delete_db_vip(self, context, id):
# proxy the call until plugin inherits from DBPlugin
super(LoadBalancerPlugin, self).delete_vip(context, id)
def delete_vip(self, context, id):
self.update_status(context, ldb.Vip,
id, constants.PENDING_DELETE)
v = self.get_vip(context, id)
driver = self._get_driver_for_pool(context, v['pool_id'])
driver.delete_vip(context, v)
def _get_provider_name(self, context, pool):
if ('provider' in pool and
pool['provider'] != attrs.ATTR_NOT_SPECIFIED):
provider_name = pconf.normalize_provider_name(pool['provider'])
self.validate_provider(provider_name)
return provider_name
else:
if not self.default_provider:
raise pconf.DefaultServiceProviderNotFound(
service_type=constants.LOADBALANCER)
return self.default_provider
def create_pool(self, context, pool):
provider_name = self._get_provider_name(context, pool['pool'])
p = super(LoadBalancerPlugin, self).create_pool(context, pool)
self.service_type_manager.add_resource_association(
context,
constants.LOADBALANCER,
provider_name, p['id'])
#need to add provider name to pool dict,
#because provider was not known to db plugin at pool creation
p['provider'] = provider_name
driver = self.drivers[provider_name]
driver.create_pool(context, p)
return p
def update_pool(self, context, id, pool):
if 'status' not in pool['pool']:
pool['pool']['status'] = constants.PENDING_UPDATE
old_pool = self.get_pool(context, id)
p = super(LoadBalancerPlugin, self).update_pool(context, id, pool)
driver = self._get_driver_for_provider(p['provider'])
driver.update_pool(context, old_pool, p)
return p
def _delete_db_pool(self, context, id):
# proxy the call until plugin inherits from DBPlugin
# rely on uuid uniqueness:
try:
with context.session.begin(subtransactions=True):
self.service_type_manager.del_resource_associations(
context, [id])
super(LoadBalancerPlugin, self).delete_pool(context, id)
except Exception:
# that should not happen
# if it's still a case - something goes wrong
# log the error and mark the pool as ERROR
LOG.error(_('Failed to delete pool %s, putting it in ERROR state'),
id)
with excutils.save_and_reraise_exception():
self.update_status(context, ldb.Pool,
id, constants.ERROR)
def delete_pool(self, context, id):
# check for delete conditions and update the status
# within a transaction to avoid a race
with context.session.begin(subtransactions=True):
self.update_status(context, ldb.Pool,
id, constants.PENDING_DELETE)
self._ensure_pool_delete_conditions(context, id)
p = self.get_pool(context, id)
driver = self._get_driver_for_provider(p['provider'])
driver.delete_pool(context, p)
def create_member(self, context, member):
m = super(LoadBalancerPlugin, self).create_member(context, member)
driver = self._get_driver_for_pool(context, m['pool_id'])
driver.create_member(context, m)
return m
def update_member(self, context, id, member):
if 'status' not in member['member']:
member['member']['status'] = constants.PENDING_UPDATE
old_member = self.get_member(context, id)
m = super(LoadBalancerPlugin, self).update_member(context, id, member)
driver = self._get_driver_for_pool(context, m['pool_id'])
driver.update_member(context, old_member, m)
return m
def _delete_db_member(self, context, id):
# proxy the call until plugin inherits from DBPlugin
super(LoadBalancerPlugin, self).delete_member(context, id)
def delete_member(self, context, id):
self.update_status(context, ldb.Member,
id, constants.PENDING_DELETE)
m = self.get_member(context, id)
driver = self._get_driver_for_pool(context, m['pool_id'])
driver.delete_member(context, m)
def create_health_monitor(self, context, health_monitor):
hm = super(LoadBalancerPlugin, self).create_health_monitor(
context,
health_monitor
)
return hm
def update_health_monitor(self, context, id, health_monitor):
old_hm = self.get_health_monitor(context, id)
hm = super(LoadBalancerPlugin, self).update_health_monitor(
context,
id,
health_monitor
)
with context.session.begin(subtransactions=True):
qry = context.session.query(
ldb.PoolMonitorAssociation
).filter_by(monitor_id=hm['id']).join(ldb.Pool)
for assoc in qry:
driver = self._get_driver_for_pool(context, assoc['pool_id'])
driver.update_pool_health_monitor(context, old_hm,
hm, assoc['pool_id'])
return hm
def _delete_db_pool_health_monitor(self, context, hm_id, pool_id):
super(LoadBalancerPlugin, self).delete_pool_health_monitor(context,
hm_id,
pool_id)
def _delete_db_health_monitor(self, context, id):
super(LoadBalancerPlugin, self).delete_health_monitor(context, id)
def delete_health_monitor(self, context, id):
with context.session.begin(subtransactions=True):
hm = self.get_health_monitor(context, id)
qry = context.session.query(
ldb.PoolMonitorAssociation
).filter_by(monitor_id=id).join(ldb.Pool)
for assoc in qry:
driver = self._get_driver_for_pool(context, assoc['pool_id'])
driver.delete_pool_health_monitor(context,
hm,
assoc['pool_id'])
super(LoadBalancerPlugin, self).delete_health_monitor(context, id)
def create_pool_health_monitor(self, context, health_monitor, pool_id):
retval = super(LoadBalancerPlugin, self).create_pool_health_monitor(
context,
health_monitor,
pool_id
)
monitor_id = health_monitor['health_monitor']['id']
hm = self.get_health_monitor(context, monitor_id)
driver = self._get_driver_for_pool(context, pool_id)
driver.create_pool_health_monitor(context, hm, pool_id)
return retval
def delete_pool_health_monitor(self, context, id, pool_id):
self.update_pool_health_monitor(context, id, pool_id,
constants.PENDING_DELETE)
hm = self.get_health_monitor(context, id)
driver = self._get_driver_for_pool(context, pool_id)
driver.delete_pool_health_monitor(context, hm, pool_id)
def stats(self, context, pool_id):
driver = self._get_driver_for_pool(context, pool_id)
stats_data = driver.stats(context, pool_id)
# if we get something from the driver -
# update the db and return the value from db
# else - return what we have in db
if stats_data:
super(LoadBalancerPlugin, self).update_pool_stats(
context,
pool_id,
stats_data
)
return super(LoadBalancerPlugin, self).stats(context,
pool_id)
def populate_vip_graph(self, context, vip):
"""Populate the vip with: pool, members, healthmonitors."""
pool = self.get_pool(context, vip['pool_id'])
vip['pool'] = pool
vip['members'] = [self.get_member(context, member_id)
for member_id in pool['members']]
vip['health_monitors'] = [self.get_health_monitor(context, hm_id)
for hm_id in pool['health_monitors']]
return vip
def validate_provider(self, provider):
if provider not in self.drivers:
raise pconf.ServiceProviderNotFound(
provider=provider, service_type=constants.LOADBALANCER)