Adopt neutron-lib plugin directory

Neutron Manager is loaded at the very startup of the neutron
server process and with it plugins are loaded and stored for
lookup purposes as their references are widely used across the
entire neutron codebase.

Rather than holding these references directly in NeutronManager
this patch refactors the code so that these references are held
by a plugin directory.

This allows subprojects and other parts of the Neutron codebase
to use the directory in lieu of the manager. The result is a
leaner, cleaner, and more decoupled code.

Usage pattern [1,2] can be translated to [3,4] respectively.

[1] manager.NeutronManager.get_service_plugins()[FOO]
[2] manager.NeutronManager.get_plugin()
[3] directory.get_plugin(FOO)
[4] directory.get_plugin()

The more entangled part is in the neutron unit tests, where the
use of the manager can be simplified as mocking is typically
replaced by a call to the directory add_plugin() method. This is
safe as each test case gets its own copy of the plugin directory.
That said, unit tests that look more like API tests and that rely on
the entire plugin machinery, need some tweaking to avoid stumbling
into plugin loading failures.

Due to the massive use of the manager, deprecation warnings are
considered impractical as they cause logs to bloat out of proportion.

Follow-up patches that show how to adopt the directory in neutron
subprojects are tagged with topic:plugin-directory.

NeutronLibImpact

Partially-implements: blueprint neutron-lib

Change-Id: I7331e914234c5f0b7abe836604fdd7e4067551cf

doc/source/devref/service_extensions.rst

@@ -55,14 +55,14 @@ Calling the Core Plugin from Services
 
 There are many cases where a service may want to create a resource
 managed by the core plugin (e.g. ports, networks, subnets). This
-can be achieved by importing the Neutron Manager and getting a direct
+can be achieved by importing the plugins directory and getting a direct
 reference to the core plugin:
 
 .. code:: python
 
-   from neutron import manager
+   from neutron_lib.plugins import directory
 
-   plugin = manager.NeutronManager.get_plugin()
+   plugin = directory.get_plugin()
    plugin.create_port(context, port_dict)
 
 

neutron/api/extensions.py

@@ -18,6 +18,7 @@ import collections
 import imp
 import os
 
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 from oslo_middleware import base
@@ -29,7 +30,6 @@ import webob.exc
 from neutron._i18n import _, _LE, _LI, _LW
 from neutron.common import exceptions
 import neutron.extensions
-from neutron import manager
 from neutron.plugins.common import constants as const
 from neutron.services import provider_configuration
 from neutron import wsgi
@@ -665,7 +665,7 @@ class PluginAwareExtensionManager(ExtensionManager):
     @classmethod
     def get_instance(cls):
         if cls._instance is None:
-            service_plugins = manager.NeutronManager.get_service_plugins()
+            service_plugins = directory.get_plugins()
             cls._instance = cls(get_extensions_path(service_plugins),
                                 service_plugins)
         return cls._instance

neutron/api/rpc/agentnotifiers/dhcp_rpc_agent_api.py

@@ -14,6 +14,7 @@
 # limitations under the License.
 
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 import oslo_messaging
@@ -26,7 +27,6 @@ from neutron.common import constants as n_const
 from neutron.common import rpc as n_rpc
 from neutron.common import topics
 from neutron.common import utils
-from neutron import manager
 
 
 LOG = logging.getLogger(__name__)
@@ -90,7 +90,7 @@ class DhcpAgentNotifyAPI(object):
     @property
     def plugin(self):
         if self._plugin is None:
-            self._plugin = manager.NeutronManager.get_plugin()
+            self._plugin = directory.get_plugin()
         return self._plugin
 
     def _schedule_network(self, context, network, existing_agents):
@@ -166,8 +166,7 @@ class DhcpAgentNotifyAPI(object):
             if 'subnet' in payload and payload['subnet'].get('segment_id'):
                 # if segment_id exists then the segment service plugin
                 # must be loaded
-                nm = manager.NeutronManager
+                segment_plugin = directory.get_plugin('segments')
-                segment_plugin = nm.get_service_plugins()['segments']
                 segment = segment_plugin.get_segment(
                     context, payload['subnet']['segment_id'])
                 network['candidate_hosts'] = segment['hosts']

neutron/api/rpc/agentnotifiers/l3_rpc_agent_api.py

@@ -16,6 +16,7 @@
 import random
 
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_log import log as logging
 import oslo_messaging
 
@@ -24,8 +25,6 @@ from neutron.api.rpc.agentnotifiers import utils as ag_utils
 from neutron.common import rpc as n_rpc
 from neutron.common import topics
 from neutron.common import utils
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 
 
 LOG = logging.getLogger(__name__)
@@ -57,8 +56,7 @@ class L3AgentNotifyAPI(object):
                             shuffle_agents):
         """Notify changed routers to hosting l3 agents."""
         adminContext = context if context.is_admin else context.elevated()
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         for router_id in router_ids:
             hosts = plugin.get_hosts_to_notify(adminContext, router_id)
             if shuffle_agents:
@@ -87,8 +85,7 @@ class L3AgentNotifyAPI(object):
     def _notification(self, context, method, router_ids, operation,
                       shuffle_agents, schedule_routers=True):
         """Notify all the agents that are hosting the routers."""
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         if not plugin:
             LOG.error(_LE('No plugin for L3 routing registered. Cannot notify '
                           'agents with the message %s'), method)

neutron/api/rpc/agentnotifiers/metering_rpc_agent_api.py

@@ -13,6 +13,7 @@
 # under the License.
 
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_log import log as logging
 import oslo_messaging
 import six
@@ -21,8 +22,6 @@ from neutron.common import rpc as n_rpc
 from neutron.common import topics
 from neutron.common import utils
 from neutron.db import agentschedulers_db
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 
 LOG = logging.getLogger(__name__)
 
@@ -38,8 +37,7 @@ class MeteringAgentNotifyAPI(object):
     def _agent_notification(self, context, method, routers):
         """Notify l3 metering agents hosted by l3 agent hosts."""
         adminContext = context if context.is_admin else context.elevated()
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
 
         l3_routers = {}
         state = agentschedulers_db.get_admin_state_up_filter()
@@ -74,8 +72,7 @@ class MeteringAgentNotifyAPI(object):
 
     def _notification(self, context, method, routers):
         """Notify all the agents that are hosting the routers."""
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         if utils.is_extension_supported(
             plugin, constants.L3_AGENT_SCHEDULER_EXT_ALIAS):
             self._agent_notification(context, method, routers)

neutron/api/rpc/callbacks/version_manager.py

@@ -15,11 +15,11 @@ import copy
 import pprint
 import time
 
+from neutron_lib.plugins import directory
 from oslo_log import log as logging
 from oslo_utils import importutils
 
 from neutron.api.rpc.callbacks import exceptions
-from neutron import manager
 
 LOG = logging.getLogger(__name__)
 
@@ -196,7 +196,7 @@ class CachedResourceConsumerTracker(object):
 
     def _update_consumer_versions(self):
         new_tracker = ResourceConsumerTracker()
-        neutron_plugin = manager.NeutronManager.get_plugin()
+        neutron_plugin = directory.get_plugin()
         agents_db = _import_agents_db()
         # If you use RPC callbacks, your plugin needs to implement
         # AgentsDbMixin so that we know which resource versions your

neutron/api/rpc/handlers/dhcp_rpc.py

@@ -19,6 +19,7 @@ import operator
 
 from neutron_lib import constants
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_log import log as logging
@@ -34,7 +35,6 @@ from neutron.db import api as db_api
 from neutron.db import provisioning_blocks
 from neutron.extensions import portbindings
 from neutron.extensions import segment as segment_ext
-from neutron import manager
 from neutron.plugins.common import utils as p_utils
 from neutron.quota import resource_registry
 
@@ -79,7 +79,7 @@ class DhcpRpcCallback(object):
     def _get_active_networks(self, context, **kwargs):
         """Retrieve and return a list of the active networks."""
         host = kwargs.get('host')
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         if utils.is_extension_supported(
             plugin, constants.DHCP_AGENT_SCHEDULER_EXT_ALIAS):
             if cfg.CONF.network_auto_schedule:
@@ -140,7 +140,7 @@ class DhcpRpcCallback(object):
         host = kwargs.get('host')
         LOG.debug('get_active_networks_info from %s', host)
         networks = self._get_active_networks(context, **kwargs)
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         filters = {'network_id': [network['id'] for network in networks]}
         ports = plugin.get_ports(context, filters=filters)
         filters['enable_dhcp'] = [True]
@@ -153,7 +153,7 @@ class DhcpRpcCallback(object):
         # inside a segment.  If the segment service plugin is loaded and
         # there are active dhcp enabled subnets, then filter out the subnets
         # that are not on the host's segment.
-        seg_plug = manager.NeutronManager.get_service_plugins().get(
+        seg_plug = directory.get_plugin(
             segment_ext.SegmentPluginBase.get_plugin_type())
         seg_subnets = [subnet for subnet in subnets
                        if subnet.get('segment_id')]
@@ -189,7 +189,7 @@ class DhcpRpcCallback(object):
         LOG.debug('Network %(network_id)s requested from '
                   '%(host)s', {'network_id': network_id,
                                'host': host})
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         try:
             network = plugin.get_network(context, network_id)
         except exceptions.NetworkNotFound:
@@ -198,7 +198,7 @@ class DhcpRpcCallback(object):
             return
         filters = dict(network_id=[network_id])
         subnets = plugin.get_subnets(context, filters=filters)
-        seg_plug = manager.NeutronManager.get_service_plugins().get(
+        seg_plug = directory.get_plugin(
             segment_ext.SegmentPluginBase.get_plugin_type())
         if seg_plug and subnets:
             seg_subnets = [subnet for subnet in subnets
@@ -231,7 +231,7 @@ class DhcpRpcCallback(object):
         LOG.debug('DHCP port deletion for %(network_id)s request from '
                   '%(host)s',
                   {'network_id': network_id, 'host': host})
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         plugin.delete_ports_by_device_id(context, device_id, network_id)
 
     @db_api.retry_db_errors
@@ -255,7 +255,7 @@ class DhcpRpcCallback(object):
         port['port'][portbindings.HOST_ID] = host
         if 'mac_address' not in port['port']:
             port['port']['mac_address'] = constants.ATTR_NOT_SPECIFIED
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         return self._port_action(plugin, context, port, 'create_port')
 
     @db_api.retry_db_errors
@@ -265,7 +265,7 @@ class DhcpRpcCallback(object):
         port = kwargs.get('port')
         port['id'] = kwargs.get('port_id')
         port['port'][portbindings.HOST_ID] = host
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         try:
             old_port = plugin.get_port(context, port['id'])
             if (old_port['device_id'] != n_const.DEVICE_ID_RESERVED_DHCP_PORT

neutron/api/rpc/handlers/dvr_rpc.py

@@ -13,6 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.plugins import directory
 from oslo_log import helpers as log_helpers
 from oslo_log import log as logging
 import oslo_messaging
@@ -20,7 +21,6 @@ import oslo_messaging
 from neutron.common import constants
 from neutron.common import rpc as n_rpc
 from neutron.common import topics
-from neutron import manager
 
 LOG = logging.getLogger(__name__)
 
@@ -85,7 +85,7 @@ class DVRServerRpcCallback(object):
     @property
     def plugin(self):
         if not getattr(self, '_plugin', None):
-            self._plugin = manager.NeutronManager.get_plugin()
+            self._plugin = directory.get_plugin()
         return self._plugin
 
     def get_dvr_mac_address_list(self, context):

neutron/api/rpc/handlers/l3_rpc.py

@@ -15,6 +15,7 @@
 
 from neutron_lib import constants
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 import oslo_messaging
@@ -26,8 +27,6 @@ from neutron import context as neutron_context
 from neutron.db import api as db_api
 from neutron.extensions import l3
 from neutron.extensions import portbindings
-from neutron import manager
-from neutron.plugins.common import constants as plugin_constants
 
 
 LOG = logging.getLogger(__name__)
@@ -52,14 +51,13 @@ class L3RpcCallback(object):
     @property
     def plugin(self):
         if not hasattr(self, '_plugin'):
-            self._plugin = manager.NeutronManager.get_plugin()
+            self._plugin = directory.get_plugin()
         return self._plugin
 
     @property
     def l3plugin(self):
         if not hasattr(self, '_l3plugin'):
-            self._l3plugin = manager.NeutronManager.get_service_plugins()[
+            self._l3plugin = directory.get_plugin(constants.L3)
-                plugin_constants.L3_ROUTER_NAT]
         return self._l3plugin
 
     def get_router_ids(self, context, host):
@@ -209,8 +207,7 @@ class L3RpcCallback(object):
         return net_id
 
     def get_service_plugin_list(self, context, **kwargs):
-        plugins = manager.NeutronManager.get_service_plugins()
+        return directory.get_plugins().keys()
-        return plugins.keys()
 
     @db_api.retry_db_errors
     def update_floatingip_statuses(self, context, router_id, fip_statuses):

neutron/api/rpc/handlers/metadata_rpc.py

@@ -13,10 +13,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from neutron_lib.plugins import directory
 import oslo_messaging
 
 from neutron.common import constants
-from neutron import manager
 
 
 class MetadataRpcCallback(object):
@@ -36,7 +36,7 @@ class MetadataRpcCallback(object):
     @property
     def plugin(self):
         if not hasattr(self, '_plugin'):
-            self._plugin = manager.NeutronManager.get_plugin()
+            self._plugin = directory.get_plugin()
         return self._plugin
 
     def get_ports(self, context, filters):

neutron/api/rpc/handlers/securitygroups_rpc.py

@@ -12,6 +12,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.plugins import directory
 from oslo_log import log as logging
 import oslo_messaging
 
@@ -20,7 +21,6 @@ from neutron.common import constants
 from neutron.common import rpc as n_rpc
 from neutron.common import topics
 from neutron.common import utils
-from neutron import manager
 
 LOG = logging.getLogger(__name__)
 
@@ -74,7 +74,7 @@ class SecurityGroupServerRpcCallback(object):
 
     @property
     def plugin(self):
-        return manager.NeutronManager.get_plugin()
+        return directory.get_plugin()
 
     def _get_devices_info(self, context, devices):
         return dict(

neutron/api/v2/resource_helper.py

@@ -13,13 +13,13 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 
 from neutron.api import extensions
 from neutron.api.v2 import base
-from neutron import manager
-from neutron.plugins.common import constants
 from neutron.quota import resource_registry
 
 LOG = logging.getLogger(__name__)
@@ -73,10 +73,7 @@ def build_resource_info(plural_mappings, resource_map, which_service,
         which_service = constants.CORE
     if action_map is None:
         action_map = {}
-    if which_service != constants.CORE:
+    plugin = directory.get_plugin(which_service)
-        plugin = manager.NeutronManager.get_service_plugins()[which_service]
-    else:
-        plugin = manager.NeutronManager.get_plugin()
     path_prefix = getattr(plugin, "path_prefix", "")
     LOG.debug('Service %(service)s assigned prefix: %(prefix)s',
               {'service': which_service, 'prefix': path_prefix})

neutron/api/v2/router.py

@@ -14,6 +14,7 @@
 # limitations under the License.
 
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_service import wsgi as base_wsgi
 import routes as routes_mapper
@@ -73,7 +74,8 @@ class APIRouter(base_wsgi.Router):
 
     def __init__(self, **local_config):
         mapper = routes_mapper.Mapper()
-        plugin = manager.NeutronManager.get_plugin()
+        manager.init()
+        plugin = directory.get_plugin()
         ext_mgr = extensions.PluginAwareExtensionManager.get_instance()
         ext_mgr.extend_resources("2.0", attributes.RESOURCE_ATTRIBUTE_MAP)
 

neutron/cmd/eventlet/usage_audit.py

@@ -19,11 +19,13 @@ subnets.
 
 import sys
 
+from neutron_lib import constants
+from neutron_lib.plugins import directory
+
 from neutron.common import config
 from neutron.common import rpc as n_rpc
 from neutron import context
 from neutron import manager
-from neutron.plugins.common import constants
 
 
 def main():
@@ -31,9 +33,9 @@ def main():
     config.setup_logging()
 
     cxt = context.get_admin_context()
-    plugin = manager.NeutronManager.get_plugin()
+    manager.init()
-    l3_plugin = manager.NeutronManager.get_service_plugins().get(
+    plugin = directory.get_plugin()
-            constants.L3_ROUTER_NAT)
+    l3_plugin = directory.get_plugin(constants.L3)
     notifier = n_rpc.get_notifier('network')
     for network in plugin.get_networks(cxt):
         notifier.info(cxt, 'network.exists', {'network': network})

neutron/core_extensions/qos.py

@@ -13,10 +13,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.plugins import directory
+
 from neutron.common import exceptions as n_exc
 from neutron.core_extensions import base
 from neutron.db import api as db_api
-from neutron import manager
 from neutron.objects.qos import policy as policy_object
 from neutron.plugins.common import constants as plugin_constants
 from neutron.services.qos import qos_consts
@@ -27,8 +28,8 @@ class QosCoreResourceExtension(base.CoreResourceExtension):
     @property
     def plugin_loaded(self):
         if not hasattr(self, '_plugin_loaded'):
-            service_plugins = manager.NeutronManager.get_service_plugins()
+            self._plugin_loaded = (
-            self._plugin_loaded = plugin_constants.QOS in service_plugins
+                plugin_constants.QOS in directory.get_plugins())
         return self._plugin_loaded
 
     def _get_policy_obj(self, context, policy_id):

neutron/db/agents_db.py

@@ -19,6 +19,7 @@ import debtcollector
 from eventlet import greenthread
 from neutron_lib.api import converters
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 import oslo_messaging
@@ -43,7 +44,6 @@ from neutron.db import api as db_api
 from neutron.db.models import agent as agent_model
 from neutron.extensions import agent as ext_agent
 from neutron.extensions import availability_zone as az_ext
-from neutron import manager
 
 LOG = logging.getLogger(__name__)
 
@@ -455,7 +455,7 @@ class AgentExtRpcCallback(object):
                       "server start timestamp: %(server_time)s", log_dict)
             return
         if not self.plugin:
-            self.plugin = manager.NeutronManager.get_plugin()
+            self.plugin = directory.get_plugin()
         agent_status, agent_state = self.plugin.create_or_update_agent(
             context, agent_state)
         self._update_local_agent_resource_versions(context, agent_state)

neutron/db/db_base_plugin_v2.py

@@ -20,6 +20,7 @@ from neutron_lib.api import validators
 from neutron_lib import constants
 from neutron_lib.db import utils as db_utils
 from neutron_lib import exceptions as exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as os_db_exc
 from oslo_db.sqlalchemy import utils as sa_utils
@@ -55,11 +56,9 @@ from neutron.extensions import l3
 from neutron import ipam
 from neutron.ipam import exceptions as ipam_exc
 from neutron.ipam import subnet_alloc
-from neutron import manager
 from neutron import neutron_plugin_base_v2
 from neutron.objects import base as base_obj
 from neutron.objects import subnetpool as subnetpool_obj
-from neutron.plugins.common import constants as service_constants
 
 
 LOG = logging.getLogger(__name__)
@@ -584,8 +583,7 @@ class NeutronDbPluginV2(db_base_plugin_common.DbBasePluginCommon,
             raise exc.BadRequest(resource='subnets', msg=reason)
 
     def _update_router_gw_ports(self, context, network, subnet):
-        l3plugin = manager.NeutronManager.get_service_plugins().get(
+        l3plugin = directory.get_plugin(constants.L3)
-                service_constants.L3_ROUTER_NAT)
         if l3plugin:
             gw_ports = self._get_router_gw_ports_by_network(context,
                     network['id'])
@@ -1343,9 +1341,7 @@ class NeutronDbPluginV2(db_base_plugin_common.DbBasePluginCommon,
                     except l3.RouterNotFound:
                         return
                 else:
-                    l3plugin = (
+                    l3plugin = directory.get_plugin(constants.L3)
-                        manager.NeutronManager.get_service_plugins().get(
-                            service_constants.L3_ROUTER_NAT))
                     if l3plugin:
                         try:
                             ctx_admin = context.elevated()

neutron/db/dvr_mac_db.py

@@ -15,6 +15,7 @@
 
 from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_log import helpers as log_helpers
@@ -33,7 +34,6 @@ from neutron.db.models import dvr as dvr_models
 from neutron.db import models_v2
 from neutron.extensions import dvr as ext_dvr
 from neutron.extensions import portbindings
-from neutron import manager
 
 _deprecate._moved_global('DistributedVirtualRouterMacAddress',
                          new_module=dvr_models)
@@ -61,7 +61,7 @@ cfg.CONF.register_opts(dvr_mac_address_opts)
 def _delete_mac_associated_with_agent(resource, event, trigger, context, agent,
                                       **kwargs):
     host = agent['host']
-    plugin = manager.NeutronManager.get_plugin()
+    plugin = directory.get_plugin()
     if [a for a in plugin.get_agents(context, filters={'host': [host]})
             if a['id'] != agent['id']]:
         # there are still agents on this host, don't mess with the mac entry
@@ -98,7 +98,7 @@ class DVRDbMixin(ext_dvr.DVRMacAddressPluginBase):
                 return self._plugin
         except AttributeError:
             pass
-        self._plugin = manager.NeutronManager.get_plugin()
+        self._plugin = directory.get_plugin()
         return self._plugin
 
     def _get_dvr_mac_address_by_host(self, context, host):

neutron/db/external_net_db.py

@@ -14,8 +14,9 @@
 #    under the License.
 
 from neutron_lib.api import validators
-from neutron_lib import constants as lib_constants
+from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from sqlalchemy.orm import exc
 from sqlalchemy.sql import expression as expr
 
@@ -34,11 +35,9 @@ from neutron.db import models_v2
 from neutron.db import rbac_db_models as rbac_db
 from neutron.extensions import external_net
 from neutron.extensions import rbac as rbac_ext
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 
 
-DEVICE_OWNER_ROUTER_GW = lib_constants.DEVICE_OWNER_ROUTER_GW
+DEVICE_OWNER_ROUTER_GW = constants.DEVICE_OWNER_ROUTER_GW
 
 _deprecate._moved_global('ExternalNetwork', new_module=ext_net_models)
 
@@ -180,8 +179,7 @@ class External_net_db_mixin(object):
             net_data[external_net.EXTERNAL] = False
 
     def _process_l3_delete(self, context, network_id):
-        l3plugin = manager.NeutronManager.get_service_plugins().get(
+        l3plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         if l3plugin:
             l3plugin.delete_disassociated_floatingips(context, network_id)
 

neutron/db/l3_agentschedulers_db.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_log import log as logging
@@ -36,8 +37,6 @@ from neutron.db.models import l3_attrs
 from neutron.db.models import l3agent as rb_model
 from neutron.extensions import l3agentscheduler
 from neutron.extensions import router_availability_zone as router_az
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 
 
 _deprecate._moved_global('RouterL3AgentBinding',
@@ -169,8 +168,7 @@ class L3AgentSchedulerDbMixin(l3agentscheduler.L3AgentSchedulerPluginBase,
         router_id = router['id']
         agent_id = agent['id']
         if self.router_scheduler:
-            plugin = manager.NeutronManager.get_service_plugins().get(
+            plugin = directory.get_plugin(constants.L3)
-                service_constants.L3_ROUTER_NAT)
             try:
                 if router.get('ha'):
                     self.router_scheduler.create_ha_port_and_bind(
@@ -217,8 +215,7 @@ class L3AgentSchedulerDbMixin(l3agentscheduler.L3AgentSchedulerPluginBase,
         self._unbind_router(context, router_id, agent_id)
 
         router = self.get_router(context, router_id)
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         if router.get('ha'):
             plugin.delete_ha_interfaces_on_host(context, router_id, agent.host)
         # NOTE(Swami): Need to verify if there are DVR serviceable

neutron/db/l3_db.py

@@ -18,8 +18,9 @@ import itertools
 from debtcollector import removals
 import netaddr
 from neutron_lib.api import validators
-from neutron_lib import constants as lib_constants
+from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_log import log as logging
 from oslo_utils import excutils
 from oslo_utils import uuidutils
@@ -46,8 +47,6 @@ from neutron.db import models_v2
 from neutron.db import standardattrdescription_db as st_attr
 from neutron.extensions import external_net
 from neutron.extensions import l3
-from neutron import manager
-from neutron.plugins.common import constants
 from neutron.plugins.common import utils as p_utils
 
 LOG = logging.getLogger(__name__)
@@ -58,10 +57,10 @@ _deprecate._moved_global('Router', new_module=l3_models)
 _deprecate._moved_global('FloatingIP', new_module=l3_models)
 
 
-DEVICE_OWNER_HA_REPLICATED_INT = lib_constants.DEVICE_OWNER_HA_REPLICATED_INT
+DEVICE_OWNER_HA_REPLICATED_INT = constants.DEVICE_OWNER_HA_REPLICATED_INT
-DEVICE_OWNER_ROUTER_INTF = lib_constants.DEVICE_OWNER_ROUTER_INTF
+DEVICE_OWNER_ROUTER_INTF = constants.DEVICE_OWNER_ROUTER_INTF
-DEVICE_OWNER_ROUTER_GW = lib_constants.DEVICE_OWNER_ROUTER_GW
+DEVICE_OWNER_ROUTER_GW = constants.DEVICE_OWNER_ROUTER_GW
-DEVICE_OWNER_FLOATINGIP = lib_constants.DEVICE_OWNER_FLOATINGIP
+DEVICE_OWNER_FLOATINGIP = constants.DEVICE_OWNER_FLOATINGIP
 EXTERNAL_GW_INFO = l3.EXTERNAL_GW_INFO
 
 # Maps API field to DB column
@@ -108,7 +107,7 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
 
     @property
     def _core_plugin(self):
-        return manager.NeutronManager.get_plugin()
+        return directory.get_plugin()
 
     def _get_router(self, context, router_id):
         try:
@@ -224,13 +223,13 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
     @db_api.retry_if_session_inactive()
     def update_router(self, context, id, router):
         r = router['router']
-        gw_info = r.pop(EXTERNAL_GW_INFO, lib_constants.ATTR_NOT_SPECIFIED)
+        gw_info = r.pop(EXTERNAL_GW_INFO, constants.ATTR_NOT_SPECIFIED)
         original = self.get_router(context, id)
         # check whether router needs and can be rescheduled to the proper
         # l3 agent (associated with given external network);
         # do check before update in DB as an exception will be raised
         # in case no proper l3 agent found
-        if gw_info != lib_constants.ATTR_NOT_SPECIFIED:
+        if gw_info != constants.ATTR_NOT_SPECIFIED:
             candidates = self._check_router_needs_rescheduling(
                 context, id, gw_info)
             # Update the gateway outside of the DB update since it involves L2
@@ -241,8 +240,7 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
             candidates = None
         router_db = self._update_router_db(context, id, r)
         if candidates:
-            l3_plugin = manager.NeutronManager.get_service_plugins().get(
+            l3_plugin = directory.get_plugin(constants.L3)
-                constants.L3_ROUTER_NAT)
             l3_plugin.reschedule_router(context, id, candidates)
         updated = self._make_router_dict(router_db)
         registry.notify(resources.ROUTER, events.AFTER_UPDATE, self,
@@ -278,11 +276,10 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
 
         # first get plugin supporting l3 agent scheduling
         # (either l3 service plugin or core_plugin)
-        l3_plugin = manager.NeutronManager.get_service_plugins().get(
+        l3_plugin = directory.get_plugin(constants.L3)
-            constants.L3_ROUTER_NAT)
         if (not utils.is_extension_supported(
                 l3_plugin,
-                lib_constants.L3_AGENT_SCHEDULER_EXT_ALIAS) or
+                constants.L3_AGENT_SCHEDULER_EXT_ALIAS) or
             l3_plugin.router_scheduler is None):
             # that might mean that we are dealing with non-agent-based
             # implementation of l3 services
@@ -321,7 +318,7 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
         # Port has no 'tenant-id', as it is hidden from user
         port_data = {'tenant_id': '',  # intentionally not set
                      'network_id': network_id,
-                     'fixed_ips': ext_ips or lib_constants.ATTR_NOT_SPECIFIED,
+                     'fixed_ips': ext_ips or constants.ATTR_NOT_SPECIFIED,
                      'device_id': router['id'],
                      'device_owner': DEVICE_OWNER_ROUTER_GW,
                      'admin_state_up': True,
@@ -1023,11 +1020,11 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
             RouterPort.router_id, models_v2.IPAllocation.ip_address).join(
             models_v2.Port, models_v2.IPAllocation).filter(
             models_v2.Port.network_id == internal_port['network_id'],
-            RouterPort.port_type.in_(lib_constants.ROUTER_INTERFACE_OWNERS),
+            RouterPort.port_type.in_(constants.ROUTER_INTERFACE_OWNERS),
             models_v2.IPAllocation.subnet_id == internal_subnet['id']
         ).join(gw_port, gw_port.device_id == RouterPort.router_id).filter(
             gw_port.network_id == external_network_id,
-            gw_port.device_owner == lib_constants.DEVICE_OWNER_ROUTER_GW
+            gw_port.device_owner == constants.DEVICE_OWNER_ROUTER_GW
         ).distinct()
 
         first_router_id = None
@@ -1172,7 +1169,7 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
             gw_port = router.gw_port
             for fixed_ip in gw_port.fixed_ips:
                 addr = netaddr.IPAddress(fixed_ip.ip_address)
-                if addr.version == lib_constants.IP_VERSION_4:
+                if addr.version == constants.IP_VERSION_4:
                     next_hop = fixed_ip.ip_address
                     break
         return {'fixed_ip_address': internal_ip_address,
@@ -1190,7 +1187,7 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
         return any(s.ip_version == 4 for s in net.subnets)
 
     def _create_floatingip(self, context, floatingip,
-            initial_status=lib_constants.FLOATINGIP_STATUS_ACTIVE):
+            initial_status=constants.FLOATINGIP_STATUS_ACTIVE):
         fip = floatingip['floatingip']
         fip_id = uuidutils.generate_uuid()
 
@@ -1212,7 +1209,7 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
                 'admin_state_up': True,
                 'device_id': 'PENDING',
                 'device_owner': DEVICE_OWNER_FLOATINGIP,
-                'status': lib_constants.PORT_STATUS_NOTAPPLICABLE,
+                'status': constants.PORT_STATUS_NOTAPPLICABLE,
                 'name': ''}
         if fip.get('floating_ip_address'):
             port['fixed_ips'] = [
@@ -1278,7 +1275,7 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
 
     @db_api.retry_if_session_inactive()
     def create_floatingip(self, context, floatingip,
-            initial_status=lib_constants.FLOATINGIP_STATUS_ACTIVE):
+            initial_status=constants.FLOATINGIP_STATUS_ACTIVE):
         return self._create_floatingip(context, floatingip, initial_status)
 
     def _update_floatingip(self, context, id, floatingip):
@@ -1629,8 +1626,8 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
 
             port['subnets'] = []
             port['extra_subnets'] = []
-            port['address_scopes'] = {lib_constants.IP_VERSION_4: None,
+            port['address_scopes'] = {constants.IP_VERSION_4: None,
-                                      lib_constants.IP_VERSION_6: None}
+                                      constants.IP_VERSION_6: None}
 
             scopes = {}
             for subnet in subnets_by_network[port['network_id']]:
@@ -1665,18 +1662,18 @@ class L3_NAT_dbonly_mixin(l3.RouterPluginBase,
         for floating_ip in floating_ips:
             router = routers_dict.get(floating_ip['router_id'])
             if router:
-                router_floatingips = router.get(lib_constants.FLOATINGIP_KEY,
+                router_floatingips = router.get(constants.FLOATINGIP_KEY,
                                                 [])
                 router_floatingips.append(floating_ip)
-                router[lib_constants.FLOATINGIP_KEY] = router_floatingips
+                router[constants.FLOATINGIP_KEY] = router_floatingips
 
     def _process_interfaces(self, routers_dict, interfaces):
         for interface in interfaces:
             router = routers_dict.get(interface['device_id'])
             if router:
-                router_interfaces = router.get(lib_constants.INTERFACE_KEY, [])
+                router_interfaces = router.get(constants.INTERFACE_KEY, [])
                 router_interfaces.append(interface)
-                router[lib_constants.INTERFACE_KEY] = router_interfaces
+                router[constants.INTERFACE_KEY] = router_interfaces
 
     def _get_router_info_list(self, context, router_ids=None, active=None,
                               device_owners=None):
@@ -1803,7 +1800,7 @@ class L3_NAT_db_mixin(L3_NAT_dbonly_mixin, L3RpcNotifierMixin):
         return router_interface_info
 
     def create_floatingip(self, context, floatingip,
-            initial_status=lib_constants.FLOATINGIP_STATUS_ACTIVE):
+            initial_status=constants.FLOATINGIP_STATUS_ACTIVE):
         floatingip_dict = super(L3_NAT_db_mixin, self).create_floatingip(
             context, floatingip, initial_status)
         router_id = floatingip_dict['router_id']
@@ -1851,8 +1848,7 @@ def _prevent_l3_port_delete_callback(resource, event, trigger, **kwargs):
     context = kwargs['context']
     port_id = kwargs['port_id']
     port_check = kwargs['port_check']
-    l3plugin = manager.NeutronManager.get_service_plugins().get(
+    l3plugin = directory.get_plugin(constants.L3)
-        constants.L3_ROUTER_NAT)
     if l3plugin and port_check:
         l3plugin.prevent_l3_port_deletion(context, port_id)
 
@@ -1860,14 +1856,12 @@ def _prevent_l3_port_delete_callback(resource, event, trigger, **kwargs):
 def _notify_routers_callback(resource, event, trigger, **kwargs):
     context = kwargs['context']
     router_ids = kwargs['router_ids']
-    l3plugin = manager.NeutronManager.get_service_plugins().get(
+    l3plugin = directory.get_plugin(constants.L3)
-        constants.L3_ROUTER_NAT)
     l3plugin.notify_routers_updated(context, router_ids)
 
 
 def _notify_subnet_gateway_ip_update(resource, event, trigger, **kwargs):
-    l3plugin = manager.NeutronManager.get_service_plugins().get(
+    l3plugin = directory.get_plugin(constants.L3)
-            constants.L3_ROUTER_NAT)
     if not l3plugin:
         return
     context = kwargs['context']
@@ -1875,7 +1869,7 @@ def _notify_subnet_gateway_ip_update(resource, event, trigger, **kwargs):
     subnet_id = kwargs['subnet_id']
     query = context.session.query(models_v2.Port).filter_by(
                 network_id=network_id,
-                device_owner=lib_constants.DEVICE_OWNER_ROUTER_GW)
+                device_owner=constants.DEVICE_OWNER_ROUTER_GW)
     query = query.join(models_v2.Port.fixed_ips).filter(
                 models_v2.IPAllocation.subnet_id == subnet_id)
     router_ids = set(port['device_id'] for port in query)
@@ -1899,8 +1893,7 @@ def _notify_subnetpool_address_scope_update(resource, event,
     query = query.distinct()
 
     router_ids = [r[0] for r in query]
-    l3plugin = manager.NeutronManager.get_service_plugins().get(
+    l3plugin = directory.get_plugin(constants.L3)
-        constants.L3_ROUTER_NAT)
     l3plugin.notify_routers_updated(context, router_ids)
 
 

neutron/db/l3_dvr_db.py

@@ -16,6 +16,7 @@ import collections
 from neutron_lib.api import validators
 from neutron_lib import constants as const
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import helpers as log_helper
 from oslo_log import log as logging
@@ -39,8 +40,6 @@ from neutron.db import models_v2
 from neutron.extensions import l3
 from neutron.extensions import portbindings
 from neutron.ipam import utils as ipam_utils
-from neutron import manager
-from neutron.plugins.common import constants
 from neutron.plugins.common import utils as p_utils
 
 
@@ -505,8 +504,7 @@ class L3_NAT_with_dvr_db_mixin(l3_db.L3_NAT_db_mixin,
                 L3_NAT_with_dvr_db_mixin, self).remove_router_interface(
                     context, router_id, interface_info)
 
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(const.L3)
-            constants.L3_ROUTER_NAT)
         router_hosts_before = plugin._get_dvr_hosts_for_router(
             context, router_id)
 

neutron/db/l3_dvrscheduler_db.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 from neutron_lib import constants as n_const
+from neutron_lib.plugins import directory
 from oslo_log import log as logging
 from sqlalchemy import or_
 
@@ -27,8 +28,6 @@ from neutron.db import l3_agentschedulers_db as l3agent_sch_db
 from neutron.db.models import l3agent as rb_model
 from neutron.db import models_v2
 from neutron.extensions import portbindings
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 from neutron.plugins.ml2 import db as ml2_db
 from neutron.plugins.ml2 import models as ml2_models
 
@@ -95,8 +94,7 @@ class L3_DVRsch_db_mixin(l3agent_sch_db.L3AgentSchedulerDbMixin):
             # Make sure we create the floatingip agent gateway port
             # for the destination node if fip is associated with this
             # fixed port
-            l3plugin = manager.NeutronManager.get_service_plugins().get(
+            l3plugin = directory.get_plugin(n_const.L3)
-                service_constants.L3_ROUTER_NAT)
             (
                 l3plugin.
                 check_for_fip_and_create_agent_gw_port_on_host_if_not_exists(
@@ -372,8 +370,7 @@ def _notify_l3_agent_new_port(resource, event, trigger, **kwargs):
         return
 
     if n_utils.is_dvr_serviced(port['device_owner']):
-        l3plugin = manager.NeutronManager.get_service_plugins().get(
+        l3plugin = directory.get_plugin(n_const.L3)
-            service_constants.L3_ROUTER_NAT)
         context = kwargs['context']
         l3plugin.dvr_handle_new_service_port(context, port)
         l3plugin.update_arp_entry_for_dvr_service_port(context, port)
@@ -382,8 +379,7 @@ def _notify_l3_agent_new_port(resource, event, trigger, **kwargs):
 def _notify_port_delete(event, resource, trigger, **kwargs):
     context = kwargs['context']
     port = kwargs['port']
-    l3plugin = manager.NeutronManager.get_service_plugins().get(
+    l3plugin = directory.get_plugin(n_const.L3)
-        service_constants.L3_ROUTER_NAT)
     if port:
         port_host = port.get(portbindings.HOST_ID)
         allowed_address_pairs_list = port.get('allowed_address_pairs')
@@ -406,8 +402,7 @@ def _notify_l3_agent_port_update(resource, event, trigger, **kwargs):
         original_device_owner = original_port.get('device_owner', '')
         new_device_owner = new_port.get('device_owner', '')
         is_new_device_dvr_serviced = n_utils.is_dvr_serviced(new_device_owner)
-        l3plugin = manager.NeutronManager.get_service_plugins().get(
+        l3plugin = directory.get_plugin(n_const.L3)
-                service_constants.L3_ROUTER_NAT)
         context = kwargs['context']
         is_port_no_longer_serviced = (
             n_utils.is_dvr_serviced(original_device_owner) and

neutron/db/l3_hascheduler_db.py

@@ -13,6 +13,7 @@
 # under the License.
 
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from sqlalchemy import func
 from sqlalchemy import sql
 
@@ -25,8 +26,6 @@ from neutron.db.models import l3 as l3_models
 from neutron.db.models import l3_attrs
 from neutron.db.models import l3agent as rb_model
 from neutron.extensions import portbindings
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 
 
 class L3_HA_scheduler_db_mixin(l3_sch_db.AZL3AgentSchedulerDbMixin):
@@ -103,8 +102,7 @@ def _notify_l3_agent_ha_port_update(resource, event, trigger, **kwargs):
         if (new_device_owner == constants.DEVICE_OWNER_ROUTER_HA_INTF and
             new_port['status'] == constants.PORT_STATUS_ACTIVE and
             original_port['status'] != new_port['status']):
-            l3plugin = manager.NeutronManager.get_service_plugins().get(
+            l3plugin = directory.get_plugin(constants.L3)
-                service_constants.L3_ROUTER_NAT)
             l3plugin.l3_rpc_notifier.routers_updated_on_host(
                 context, [new_port['device_id']], host)
 

neutron/db/metering/metering_rpc.py

@@ -13,13 +13,12 @@
 # under the License.
 
 from neutron_lib import constants as consts
+from neutron_lib.plugins import directory
 from oslo_log import log as logging
 import oslo_messaging
 
 from neutron._i18n import _LE
 from neutron.common import utils
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 
 LOG = logging.getLogger(__name__)
 
@@ -32,8 +31,7 @@ class MeteringRpcCallbacks(object):
         self.meter_plugin = meter_plugin
 
     def get_sync_data_metering(self, context, **kwargs):
-        l3_plugin = manager.NeutronManager.get_service_plugins().get(
+        l3_plugin = directory.get_plugin(consts.L3)
-            service_constants.L3_ROUTER_NAT)
         if not l3_plugin:
             return
 

neutron/db/rbac_db_models.py

@@ -17,13 +17,13 @@ import abc
 
 from neutron_lib.db import model_base
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 import sqlalchemy as sa
 from sqlalchemy.ext import declarative
 from sqlalchemy.orm import validates
 
 from neutron._i18n import _
 from neutron.api.v2 import attributes as attr
-from neutron import manager
 
 
 ACCESS_SHARED = 'access_as_shared'
@@ -97,7 +97,7 @@ class NetworkRBAC(RBACColumns, model_base.BASEV2):
 
     def get_valid_actions(self):
         actions = (ACCESS_SHARED,)
-        pl = manager.NeutronManager.get_plugin()
+        pl = directory.get_plugin()
         if 'external-net' in pl.supported_extension_aliases:
             actions += (ACCESS_EXTERNAL,)
         return actions

neutron/extensions/address_scope.py

@@ -17,13 +17,13 @@ import abc
 from neutron_lib.api import converters
 from neutron_lib import constants
 from neutron_lib import exceptions as nexception
+from neutron_lib.plugins import directory
 import six
 
 from neutron._i18n import _
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
 from neutron.api.v2 import base
-from neutron import manager
 
 ADDRESS_SCOPE = 'address_scope'
 ADDRESS_SCOPES = '%ss' % ADDRESS_SCOPE
@@ -118,7 +118,7 @@ class Address_scope(extensions.ExtensionDescriptor):
         """Returns Ext Resources."""
         my_plurals = [(key, key[:-1]) for key in RESOURCE_ATTRIBUTE_MAP.keys()]
         attr.PLURALS.update(dict(my_plurals))
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         collection_name = ADDRESS_SCOPES.replace('_', '-')
         params = RESOURCE_ATTRIBUTE_MAP.get(ADDRESS_SCOPES, dict())
         controller = base.create_resource(collection_name,

neutron/extensions/agent.py

@@ -17,13 +17,13 @@ import abc
 
 from neutron_lib.api import converters
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 import six
 
 from neutron._i18n import _
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
 from neutron.api.v2 import base
-from neutron import manager
 
 
 # Attribute Map
@@ -100,7 +100,7 @@ class Agent(extensions.ExtensionDescriptor):
         """Returns Ext Resources."""
         my_plurals = [(key, key[:-1]) for key in RESOURCE_ATTRIBUTE_MAP.keys()]
         attr.PLURALS.update(dict(my_plurals))
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         params = RESOURCE_ATTRIBUTE_MAP.get(RESOURCE_NAME + 's')
         controller = base.create_resource(RESOURCE_NAME + 's',
                                           RESOURCE_NAME,

neutron/extensions/auto_allocated_topology.py

@@ -15,10 +15,10 @@
 #    under the License.
 
 from neutron_lib.api import converters
+from neutron_lib.plugins import directory
 
 from neutron.api import extensions
 from neutron.api.v2 import base
-from neutron import manager
 
 RESOURCE_NAME = "auto_allocated_topology"
 COLLECTION_NAME = "auto_allocated_topologies"
@@ -67,8 +67,7 @@ class Auto_allocated_topology(extensions.ExtensionDescriptor):
         params = RESOURCE_ATTRIBUTE_MAP.get(COLLECTION_NAME, dict())
         controller = base.create_resource(COLLECTION_NAME,
                                           EXT_ALIAS,
-                                          manager.NeutronManager.
+                                          directory.get_plugin(EXT_ALIAS),
-                                          get_service_plugins()[EXT_ALIAS],
                                           params, allow_bulk=False)
         return [extensions.ResourceExtension(EXT_ALIAS, controller)]
 

neutron/extensions/availability_zone.py

@@ -16,6 +16,7 @@ import abc
 
 from neutron_lib.api import validators
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_serialization import jsonutils
 import six
 
@@ -23,7 +24,6 @@ from neutron._i18n import _
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
 from neutron.api.v2 import base
-from neutron import manager
 
 
 AZ_HINTS_DB_LEN = 255
@@ -106,7 +106,7 @@ class Availability_zone(extensions.ExtensionDescriptor):
         """Returns Ext Resources."""
         my_plurals = [(key, key[:-1]) for key in RESOURCE_ATTRIBUTE_MAP.keys()]
         attr.PLURALS.update(dict(my_plurals))
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         params = RESOURCE_ATTRIBUTE_MAP.get(AVAILABILITY_ZONES)
         controller = base.create_resource(AVAILABILITY_ZONES,
                                           RESOURCE_NAME, plugin, params)

neutron/extensions/dhcpagentscheduler.py

@@ -17,6 +17,7 @@ import abc
 
 from neutron_lib import constants
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 import six
 
 from neutron._i18n import _
@@ -25,7 +26,6 @@ from neutron.api.v2 import base
 from neutron.api.v2 import resource
 from neutron.common import rpc as n_rpc
 from neutron.extensions import agent
-from neutron import manager
 from neutron import policy
 from neutron import wsgi
 
@@ -37,7 +37,7 @@ DHCP_AGENTS = DHCP_AGENT + 's'
 
 class NetworkSchedulerController(wsgi.Controller):
     def index(self, request, **kwargs):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         policy.enforce(request.context,
                        "get_%s" % DHCP_NETS,
                        {})
@@ -45,7 +45,7 @@ class NetworkSchedulerController(wsgi.Controller):
             request.context, kwargs['agent_id'])
 
     def create(self, request, body, **kwargs):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         policy.enforce(request.context,
                        "create_%s" % DHCP_NET,
                        {})
@@ -57,7 +57,7 @@ class NetworkSchedulerController(wsgi.Controller):
         return result
 
     def delete(self, request, id, **kwargs):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         policy.enforce(request.context,
                        "delete_%s" % DHCP_NET,
                        {})
@@ -70,7 +70,7 @@ class NetworkSchedulerController(wsgi.Controller):
 
 class DhcpAgentsHostingNetworkController(wsgi.Controller):
     def index(self, request, **kwargs):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         policy.enforce(request.context,
                        "get_%s" % DHCP_AGENTS,
                        {})

neutron/extensions/flavors.py

@@ -15,13 +15,13 @@
 from neutron_lib.api import converters
 from neutron_lib.api import validators
 from neutron_lib import exceptions as nexception
+from neutron_lib.plugins import directory
 
 from neutron._i18n import _
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
 from neutron.api.v2 import base
 from neutron.api.v2 import resource_helper
-from neutron import manager
 from neutron.plugins.common import constants
 
 
@@ -74,8 +74,7 @@ class InvalidFlavorServiceType(nexception.InvalidInput):
 
 def _validate_flavor_service_type(validate_type, valid_values=None):
     """Ensure requested flavor service type plugin is loaded."""
-    plugins = manager.NeutronManager.get_service_plugins()
+    if not directory.get_plugin(validate_type):
-    if validate_type not in plugins:
         raise InvalidFlavorServiceType(service_type=validate_type)
 
 validators.add_validator('validate_flavor_service_type',
@@ -204,8 +203,7 @@ class Flavors(extensions.ExtensionDescriptor):
             plural_mappings,
             RESOURCE_ATTRIBUTE_MAP,
             constants.FLAVORS)
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(constants.FLAVORS)
-            constants.FLAVORS]
         for collection_name in SUB_RESOURCE_ATTRIBUTE_MAP:
             # Special handling needed for sub-resources with 'y' ending
             # (e.g. proxies -> proxy)

neutron/extensions/l3agentscheduler.py

@@ -17,6 +17,7 @@ import abc
 
 from neutron_lib import constants
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_log import log as logging
 import six
 import webob.exc
@@ -27,8 +28,6 @@ from neutron.api.v2 import base
 from neutron.api.v2 import resource
 from neutron.common import rpc as n_rpc
 from neutron.extensions import agent
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 from neutron import policy
 from neutron import wsgi
 
@@ -44,8 +43,7 @@ L3_AGENTS = L3_AGENT + 's'
 
 class RouterSchedulerController(wsgi.Controller):
     def get_plugin(self):
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         if not plugin:
             LOG.error(_LE('No plugin for L3 routing registered to handle '
                           'router scheduling'))
@@ -87,8 +85,7 @@ class RouterSchedulerController(wsgi.Controller):
 
 class L3AgentsHostingRouterController(wsgi.Controller):
     def get_plugin(self):
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         if not plugin:
             LOG.error(_LE('No plugin for L3 routing registered to handle '
                           'router scheduling'))

neutron/extensions/qos.py

@@ -18,6 +18,7 @@ import itertools
 import re
 
 from neutron_lib.api import converters
+from neutron_lib.plugins import directory
 import six
 
 from neutron.api import extensions
@@ -25,7 +26,6 @@ from neutron.api.v2 import attributes as attr
 from neutron.api.v2 import base
 from neutron.api.v2 import resource_helper
 from neutron.common import constants as common_constants
-from neutron import manager
 from neutron.objects.qos import rule as rule_object
 from neutron.plugins.common import constants
 from neutron.services.qos import qos_consts
@@ -169,7 +169,7 @@ class Qos(extensions.ExtensionDescriptor):
                 translate_name=True,
                 allow_bulk=True)
 
-        plugin = manager.NeutronManager.get_service_plugins()[constants.QOS]
+        plugin = directory.get_plugin(constants.QOS)
         for collection_name in SUB_RESOURCE_ATTRIBUTE_MAP:
             resource_name = collection_name[:-1]
             parent = SUB_RESOURCE_ATTRIBUTE_MAP[collection_name].get('parent')

neutron/extensions/quotasv2.py

@@ -15,6 +15,7 @@
 
 from neutron_lib.api import converters
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_utils import importutils
 import webob
@@ -26,7 +27,6 @@ from neutron.api.v2 import base
 from neutron.api.v2 import resource
 from neutron.common import constants as const
 from neutron.common import exceptions
-from neutron import manager
 from neutron.pecan_wsgi import controllers
 from neutron.pecan_wsgi.controllers import utils as pecan_utils
 from neutron import quota
@@ -153,7 +153,7 @@ class Quotasv2(extensions.ExtensionDescriptor):
     def get_resources(cls):
         """Returns Ext Resources."""
         controller = resource.Resource(
-            QuotaSetsController(manager.NeutronManager.get_plugin()),
+            QuotaSetsController(directory.get_plugin()),
             faults=base.FAULT_MAP)
         return [extensions.ResourceExtension(
             Quotasv2.get_alias(),

neutron/extensions/rbac.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 
 from neutron._i18n import _
 from neutron.api import extensions
@@ -21,7 +22,6 @@ from neutron.api.v2 import attributes as attr
 from neutron.api.v2 import base
 from neutron.conf import quota
 from neutron.db import rbac_db_models
-from neutron import manager
 from neutron.quota import resource_registry
 
 
@@ -106,7 +106,7 @@ class Rbac(extensions.ExtensionDescriptor):
         """Returns Ext Resources."""
         plural_mappings = {'rbac_policies': 'rbac_policy'}
         attr.PLURALS.update(plural_mappings)
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         params = RESOURCE_ATTRIBUTE_MAP['rbac_policies']
         collection_name = 'rbac-policies'
         resource_name = 'rbac_policy'

neutron/extensions/securitygroup.py

@@ -19,6 +19,7 @@ import netaddr
 from neutron_lib.api import validators
 from neutron_lib import constants as const
 from neutron_lib import exceptions as nexception
+from neutron_lib.plugins import directory
 from oslo_utils import netutils
 from oslo_utils import uuidutils
 import six
@@ -29,7 +30,6 @@ from neutron.api.v2 import attributes as attr
 from neutron.api.v2 import base
 from neutron.common import exceptions
 from neutron.conf import quota
-from neutron import manager
 from neutron.quota import resource_registry
 
 
@@ -306,7 +306,7 @@ class Securitygroup(extensions.ExtensionDescriptor):
         my_plurals = [(key, key[:-1]) for key in RESOURCE_ATTRIBUTE_MAP.keys()]
         attr.PLURALS.update(dict(my_plurals))
         exts = []
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         for resource_name in ['security_group', 'security_group_rule']:
             collection_name = resource_name.replace('_', '-') + "s"
             params = RESOURCE_ATTRIBUTE_MAP.get(resource_name + "s", dict())

neutron/extensions/segment.py

@@ -17,12 +17,12 @@ import six
 
 from neutron_lib.api import converters
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 
 from neutron.api import extensions
 from neutron.api.v2 import attributes
 from neutron.api.v2 import base
 from neutron.extensions import providernet
-from neutron import manager
 
 SEGMENT = 'segment'
 SEGMENTS = '%ss' % SEGMENT
@@ -115,7 +115,7 @@ class Segment(extensions.ExtensionDescriptor):
         controller = base.create_resource(
             SEGMENTS,
             SEGMENT,
-            manager.NeutronManager.get_service_plugins()[SEGMENTS],
+            directory.get_plugin(SEGMENTS),
             resource_attributes)
         return [extensions.ResourceExtension(SEGMENTS,
                                              controller,

neutron/extensions/tag.py

@@ -15,6 +15,7 @@ import abc
 
 from neutron_lib.api import validators
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 import six
 import webob.exc
 
@@ -23,7 +24,6 @@ from neutron.api import extensions
 from neutron.api.v2 import attributes
 from neutron.api.v2 import base
 from neutron.api.v2 import resource as api_resource
-from neutron import manager
 from neutron.services import service_base
 
 
@@ -74,8 +74,7 @@ def validate_tags(body):
 
 class TagController(object):
     def __init__(self):
-        self.plugin = (manager.NeutronManager.get_service_plugins()
+        self.plugin = directory.get_plugin(TAG_PLUGIN_TYPE)
-                       [TAG_PLUGIN_TYPE])
 
     def index(self, request, **kwargs):
         # GET /v2.0/networks/{network_id}/tags

neutron/ipam/drivers/neutrondb_ipam/driver.py

@@ -18,6 +18,7 @@ import random
 
 import netaddr
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_db import exception as db_exc
 from oslo_log import log
 from oslo_utils import uuidutils
@@ -29,7 +30,6 @@ from neutron.ipam import exceptions as ipam_exc
 from neutron.ipam import requests as ipam_req
 from neutron.ipam import subnet_alloc
 from neutron.ipam import utils as ipam_utils
-from neutron import manager
 
 
 LOG = log.getLogger(__name__)
@@ -110,7 +110,7 @@ class NeutronDbSubnet(ipam_base.Subnet):
 
     @classmethod
     def _fetch_subnet(cls, context, id):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         return plugin._get_subnet(context, id)
 
     def __init__(self, internal_id, ctx, cidr=None,

neutron/manager.py

@@ -14,8 +14,8 @@
 #    under the License.
 
 from collections import defaultdict
-import weakref
+from neutron_lib import constants as lib_const
-
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 import oslo_messaging
@@ -102,8 +102,11 @@ class NeutronManager(object):
     Neutron's Manager class is responsible for parsing a config file and
     instantiating the correct plugin that concretely implements
     neutron_plugin_base class.
-    The caller should make sure that NeutronManager is a singleton.
     """
+    # TODO(armax): use of the singleton pattern for this class is vestigial,
+    # and it is mainly relied on by the unit tests. It is safer to get rid
+    # of it once the entire codebase (neutron + subprojects) has switched
+    # entirely to using the plugins directory.
     _instance = None
     __trace_args__ = {"name": "rpc"}
 
@@ -123,18 +126,17 @@ class NeutronManager(object):
         #                for performance metrics.
         plugin_provider = cfg.CONF.core_plugin
         LOG.info(_LI("Loading core plugin: %s"), plugin_provider)
-        self.plugin = self._get_plugin_instance(CORE_PLUGINS_NAMESPACE,
+        # NOTE(armax): keep hold of the actual plugin object
-                                                plugin_provider)
+        plugin = self._get_plugin_instance(CORE_PLUGINS_NAMESPACE,
+                                           plugin_provider)
+        directory.add_plugin(lib_const.CORE, plugin)
         msg = validate_post_plugin_load()
         if msg:
             LOG.critical(msg)
             raise Exception(msg)
 
-        # core plugin as a part of plugin collection simplifies
+        # load services from the core plugin first
-        # checking extensions
+        self._load_services_from_core_plugin(plugin)
-        # TODO(enikanorov): make core plugin the same as
-        # the rest of service plugins
-        self.service_plugins = {constants.CORE: self.plugin}
         self._load_service_plugins()
         # Used by pecan WSGI
         self.resource_plugin_mappings = {}
@@ -161,16 +163,15 @@ class NeutronManager(object):
         plugin_class = self.load_class_for_provider(namespace, plugin_provider)
         return plugin_class()
 
-    def _load_services_from_core_plugin(self):
+    def _load_services_from_core_plugin(self, plugin):
         """Puts core plugin in service_plugins for supported services."""
         LOG.debug("Loading services supported by the core plugin")
 
         # supported service types are derived from supported extensions
-        for ext_alias in getattr(self.plugin,
+        for ext_alias in getattr(plugin, "supported_extension_aliases", []):
-                                 "supported_extension_aliases", []):
             if ext_alias in constants.EXT_TO_SERVICE_MAPPING:
                 service_type = constants.EXT_TO_SERVICE_MAPPING[ext_alias]
-                self.service_plugins[service_type] = self.plugin
+                directory.add_plugin(service_type, plugin)
                 LOG.info(_LI("Service %s is supported by the core plugin"),
                          service_type)
 
@@ -184,9 +185,6 @@ class NeutronManager(object):
         Starts from the core plugin and checks if it supports
         advanced services then loads classes provided in configuration.
         """
-        # load services from the core plugin first
-        self._load_services_from_core_plugin()
-
         plugin_providers = cfg.CONF.service_plugins
         plugin_providers.extend(self._get_default_service_plugins())
         LOG.debug("Loading service plugins: %s", plugin_providers)
@@ -201,22 +199,25 @@ class NeutronManager(object):
             # only one implementation of svc_type allowed
             # specifying more than one plugin
             # for the same type is a fatal exception
-            if plugin_inst.get_plugin_type() in self.service_plugins:
+            # TODO(armax): simplify this by moving the conditional into the
+            # directory itself.
+            plugin_type = plugin_inst.get_plugin_type()
+            if directory.get_plugin(plugin_type):
                 raise ValueError(_("Multiple plugins for service "
-                                   "%s were configured") %
+                                   "%s were configured") % plugin_type)
-                                 plugin_inst.get_plugin_type())
 
-            self.service_plugins[plugin_inst.get_plugin_type()] = plugin_inst
+            directory.add_plugin(plugin_type, plugin_inst)
 
             # search for possible agent notifiers declared in service plugin
             # (needed by agent management extension)
-            if (hasattr(self.plugin, 'agent_notifiers') and
+            plugin = directory.get_plugin()
+            if (hasattr(plugin, 'agent_notifiers') and
                     hasattr(plugin_inst, 'agent_notifiers')):
-                self.plugin.agent_notifiers.update(plugin_inst.agent_notifiers)
+                plugin.agent_notifiers.update(plugin_inst.agent_notifiers)
 
             LOG.debug("Successfully loaded %(type)s plugin. "
                       "Description: %(desc)s",
-                      {"type": plugin_inst.get_plugin_type(),
+                      {"type": plugin_type,
                        "desc": plugin_inst.get_plugin_description()})
 
     @classmethod
@@ -240,23 +241,6 @@ class NeutronManager(object):
             cls._create_instance()
         return cls._instance
 
-    @classmethod
-    def get_plugin(cls):
-        # Return a weakref to minimize gc-preventing references.
-        return weakref.proxy(cls.get_instance().plugin)
-
-    @classmethod
-    def get_service_plugins(cls):
-        # Return weakrefs to minimize gc-preventing references.
-        service_plugins = cls.get_instance().service_plugins
-        return dict((x, weakref.proxy(y))
-                    for x, y in six.iteritems(service_plugins))
-
-    @classmethod
-    def get_unique_service_plugins(cls):
-        service_plugins = cls.get_instance().service_plugins
-        return tuple(weakref.proxy(x) for x in set(service_plugins.values()))
-
     @classmethod
     def set_plugin_for_resource(cls, resource, plugin):
         cls.get_instance().resource_plugin_mappings[resource] = plugin
@@ -283,7 +267,7 @@ class NeutronManager(object):
     # probably should be removed
     @classmethod
     def get_service_plugin_by_path_prefix(cls, path_prefix):
-        service_plugins = cls.get_unique_service_plugins()
+        service_plugins = directory.get_unique_plugins()
         for service_plugin in service_plugins:
             plugin_path_prefix = getattr(service_plugin, 'path_prefix', None)
             if plugin_path_prefix and plugin_path_prefix == path_prefix:
@@ -298,3 +282,10 @@ class NeutronManager(object):
     @classmethod
     def get_resources_for_path_prefix(cls, path_prefix):
         return cls.get_instance().path_prefix_resource_mappings[path_prefix]
+
+
+def init():
+    """Call to load the plugins (core+services) machinery."""
+    # TODO(armax): use is_loaded() when available
+    if not directory.get_plugins():
+        NeutronManager.get_instance()

neutron/notifiers/nova.py

@@ -16,6 +16,7 @@
 from keystoneauth1 import loading as ks_loading
 from neutron_lib import constants
 from neutron_lib import exceptions as exc
+from neutron_lib.plugins import directory
 from novaclient import client as nova_client
 from novaclient import exceptions as nova_exceptions
 from oslo_config import cfg
@@ -28,7 +29,6 @@ from neutron.callbacks import events
 from neutron.callbacks import registry
 from neutron.callbacks import resources
 from neutron import context
-from neutron import manager
 from neutron.notifiers import batch_notifier
 
 
@@ -102,15 +102,6 @@ class Notifier(object):
                 'name': VIF_DELETED,
                 'tag': port['id']}
 
-    @property
-    def _plugin(self):
-        # NOTE(arosen): this cannot be set in __init__ currently since
-        # this class is initialized 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_nova_notification(self, resource, event, trigger,
                                 action=None, original=None, data=None,
                                 **kwargs):
@@ -162,7 +153,7 @@ class Notifier(object):
 
             ctx = context.get_admin_context()
             try:
-                port = self._plugin.get_port(ctx, port_id)
+                port = directory.get_plugin().get_port(ctx, port_id)
             except exc.PortNotFound:
                 LOG.debug("Port %s was deleted, no need to send any "
                           "notification", port_id)

neutron/objects/db/api.py

@@ -14,15 +14,14 @@
 # backends
 
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_utils import uuidutils
 
-from neutron import manager
-
 
 # Common database operation implementations
 def _get_filter_query(context, model, **kwargs):
     # TODO(jlibosva): decompose _get_collection_query from plugin instance
-    plugin = manager.NeutronManager.get_plugin()
+    plugin = directory.get_plugin()
     with context.session.begin(subtransactions=True):
         filters = _kwargs_to_filters(**kwargs)
         query = plugin._get_collection_query(context, model, filters)
@@ -46,7 +45,7 @@ def get_objects(context, model, _pager=None, **kwargs):
     with context.session.begin(subtransactions=True):
         filters = _kwargs_to_filters(**kwargs)
         # TODO(ihrachys): decompose _get_collection from plugin instance
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         return plugin._get_collection(
             context, model,
             # TODO(ihrachys): avoid this no-op call per model found

neutron/objects/qos/rule_type.py

@@ -10,10 +10,10 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.plugins import directory
 from oslo_versionedobjects import base as obj_base
 from oslo_versionedobjects import fields as obj_fields
 
-from neutron import manager
 from neutron.objects import base
 from neutron.services.qos import qos_consts
 
@@ -42,7 +42,7 @@ class QosRuleType(base.NeutronObject):
     def get_objects(cls, validate_filters=True, **kwargs):
         if validate_filters:
             cls.validate_filters(**kwargs)
-        core_plugin = manager.NeutronManager.get_plugin()
+        core_plugin = directory.get_plugin()
         # TODO(ihrachys): apply filters to returned result
         return [cls(type=type_)
                 for type_ in core_plugin.supported_qos_rule_types]

neutron/pecan_wsgi/hooks/ownership_validation.py

@@ -13,11 +13,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.plugins import directory
 from pecan import hooks
 import webob
 
 from neutron._i18n import _
-from neutron import manager
 
 
 class OwnershipValidationHook(hooks.PecanHook):
@@ -38,7 +38,7 @@ class OwnershipValidationHook(hooks.PecanHook):
         if (neutron_context.is_admin or neutron_context.is_advsvc or
                 resource not in ('port', 'subnet')):
             return
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         network = plugin.get_network(neutron_context,
                                      resource_item['network_id'])
         # do not perform the check on shared networks

neutron/pecan_wsgi/startup.py

@@ -13,6 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.plugins import directory
 from oslo_log import log
 
 from neutron._i18n import _LW
@@ -31,13 +32,14 @@ LOG = log.getLogger(__name__)
 
 
 def initialize_all():
+    manager.init()
     ext_mgr = extensions.PluginAwareExtensionManager.get_instance()
     ext_mgr.extend_resources("2.0", attributes.RESOURCE_ATTRIBUTE_MAP)
     # At this stage we have a fully populated resource attribute map;
     # build Pecan controllers and routes for all core resources
     for resource, collection in router.RESOURCES.items():
         resource_registry.register_resource_by_name(resource)
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         new_controller = res_ctrl.CollectionsController(collection, resource,
                                                         plugin=plugin)
         manager.NeutronManager.set_controller_for_resource(

neutron/plugins/ml2/db.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 from neutron_lib import constants as n_const
+from neutron_lib.plugins import directory
 from oslo_db import exception as db_exc
 from oslo_log import log
 from oslo_utils import uuidutils
@@ -28,7 +29,6 @@ from neutron.callbacks import resources
 from neutron.db.models import securitygroup as sg_models
 from neutron.db import models_v2
 from neutron.extensions import portbindings
-from neutron import manager
 from neutron.plugins.ml2 import models
 from neutron.services.segments import exceptions as seg_exc
 
@@ -215,7 +215,7 @@ def get_sg_ids_grouped_by_port(context, port_ids):
 
 
 def make_port_dict_with_security_groups(port, sec_groups):
-    plugin = manager.NeutronManager.get_plugin()
+    plugin = directory.get_plugin()
     port_dict = plugin._make_port_dict(port)
     port_dict['security_groups'] = sec_groups
     port_dict['security_group_rules'] = []

neutron/plugins/ml2/drivers/l2pop/mech_driver.py

@@ -15,6 +15,7 @@
 
 from neutron_lib import constants as const
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 
@@ -22,8 +23,6 @@ from neutron._i18n import _, _LW
 from neutron import context as n_context
 from neutron.db import api as db_api
 from neutron.db import l3_hamode_db
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 from neutron.plugins.ml2 import driver_api as api
 from neutron.plugins.ml2.drivers.l2pop import config  # noqa
 from neutron.plugins.ml2.drivers.l2pop import db as l2pop_db
@@ -238,8 +237,7 @@ class L2populationMechanismDriver(api.MechanismDriver):
     def update_port_down(self, context):
         port = context.current
         agent_host = context.host
-        l3plugin = manager.NeutronManager.get_service_plugins().get(
+        l3plugin = directory.get_plugin(const.L3)
-            service_constants.L3_ROUTER_NAT)
         # when agent transitions to backup, don't remove flood flows
         if agent_host and l3plugin and getattr(
             l3plugin, "list_router_ids_on_host", None):

neutron/plugins/ml2/extensions/dns_integration.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 from neutron_lib.api import validators
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 
@@ -24,7 +25,6 @@ from neutron.callbacks import resources
 from neutron.db import models_v2
 from neutron.db import segments_db
 from neutron.extensions import dns
-from neutron import manager
 from neutron.objects import network as net_obj
 from neutron.objects import ports as port_obj
 from neutron.plugins.common import utils as plugin_utils
@@ -264,7 +264,7 @@ class DNSExtensionDriver(api.ExtensionDriver):
                                       dns_data_db)
 
     def _get_network(self, context, network_id):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         return plugin.get_network(context, network_id)
 
 

neutron/plugins/ml2/plugin.py

@@ -17,6 +17,7 @@ from eventlet import greenthread
 from neutron_lib.api import validators
 from neutron_lib import constants as const
 from neutron_lib import exceptions as exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as os_db_exception
 from oslo_log import helpers as log_helpers
@@ -71,8 +72,6 @@ from neutron.extensions import portbindings
 from neutron.extensions import portsecurity as psec
 from neutron.extensions import providernet as provider
 from neutron.extensions import vlantransparent
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 from neutron.plugins.ml2.common import exceptions as ml2_exc
 from neutron.plugins.ml2 import config  # noqa
 from neutron.plugins.ml2 import db
@@ -1591,8 +1590,7 @@ class Ml2Plugin(db_base_plugin_v2.NeutronDbPluginV2,
         self._pre_delete_port(context, id, l3_port_check)
         # TODO(armax): get rid of the l3 dependency in the with block
         router_ids = []
-        l3plugin = manager.NeutronManager.get_service_plugins().get(
+        l3plugin = directory.get_plugin(const.L3)
-            service_constants.L3_ROUTER_NAT)
 
         session = context.session
         with session.begin(subtransactions=True):

neutron/plugins/ml2/rpc.py

@@ -15,6 +15,7 @@
 
 from neutron_lib import constants as n_const
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_log import log
 import oslo_messaging
 from sqlalchemy.orm import exc
@@ -29,7 +30,6 @@ from neutron.db import l3_hamode_db
 from neutron.db import provisioning_blocks
 from neutron.extensions import portbindings
 from neutron.extensions import portsecurity as psec
-from neutron import manager
 from neutron.plugins.ml2 import db as ml2_db
 from neutron.plugins.ml2 import driver_api as api
 from neutron.plugins.ml2.drivers import type_tunnel
@@ -70,7 +70,7 @@ class RpcCallbacks(type_tunnel.TunnelRpcCallbackMixin):
                   "%(agent_id)s with host %(host)s",
                   {'device': device, 'agent_id': agent_id, 'host': host})
 
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         port_id = plugin._device_to_port_id(rpc_context, device)
         port_context = plugin.get_bound_port_context(rpc_context,
                                                      port_id,
@@ -175,7 +175,7 @@ class RpcCallbacks(type_tunnel.TunnelRpcCallbackMixin):
         LOG.debug("Device %(device)s no longer exists at agent "
                   "%(agent_id)s",
                   {'device': device, 'agent_id': agent_id})
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         port_id = plugin._device_to_port_id(rpc_context, device)
         port_exists = True
         if (host and not plugin.port_bound_to_host(rpc_context,
@@ -206,7 +206,7 @@ class RpcCallbacks(type_tunnel.TunnelRpcCallbackMixin):
         host = kwargs.get('host')
         LOG.debug("Device %(device)s up at agent %(agent_id)s",
                   {'device': device, 'agent_id': agent_id})
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         port_id = plugin._device_to_port_id(rpc_context, device)
         port = plugin.port_bound_to_host(rpc_context, port_id, host)
         if host and not port:
@@ -232,7 +232,7 @@ class RpcCallbacks(type_tunnel.TunnelRpcCallbackMixin):
                                    n_const.PORT_STATUS_ACTIVE, host, port=port)
 
     def update_port_status_to_active(self, port, rpc_context, port_id, host):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         if port and port['device_owner'] == n_const.DEVICE_OWNER_DVR_INTERFACE:
             # NOTE(kevinbenton): we have to special case DVR ports because of
             # the special multi-binding status update logic they have that
@@ -254,7 +254,7 @@ class RpcCallbacks(type_tunnel.TunnelRpcCallbackMixin):
 
     def notify_ha_port_status(self, port_id, rpc_context,
                               status, host, port=None):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         l2pop_driver = plugin.mechanism_manager.mech_drivers.get(
                 'l2population')
         if not l2pop_driver:

neutron/policy.py

@@ -18,6 +18,7 @@ import re
 
 from neutron_lib import constants
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_log import log as logging
@@ -251,11 +252,7 @@ class OwnerCheck(policy.Check):
             # resource is handled by the core plugin. It might be worth
             # having a way to map resources to plugins so to make this
             # check more general
-            # NOTE(ihrachys): if import is put in global, circular
+            f = getattr(directory.get_plugin(), 'get_%s' % parent_res)
-            # import failure occurs
-            manager = importutils.import_module('neutron.manager')
-            f = getattr(manager.NeutronManager.get_instance().plugin,
-                        'get_%s' % parent_res)
             # f *must* exist, if not found it is better to let neutron
             # explode. Check will be performed with admin context
             context = importutils.import_module('neutron.context')

neutron/service.py

@@ -17,6 +17,7 @@ import inspect
 import os
 import random
 
+from neutron_lib.plugins import directory
 from oslo_concurrency import processutils
 from oslo_config import cfg
 from oslo_log import log as logging
@@ -36,7 +37,6 @@ from neutron.common import rpc as n_rpc
 from neutron.conf import service
 from neutron import context
 from neutron.db import api as session
-from neutron import manager
 from neutron import worker as neutron_worker
 from neutron import wsgi
 
@@ -150,9 +150,8 @@ class RpcReportsWorker(RpcWorker):
 
 
 def _get_rpc_workers():
-    plugin = manager.NeutronManager.get_plugin()
+    plugin = directory.get_plugin()
-    service_plugins = (
+    service_plugins = directory.get_plugins().values()
-        manager.NeutronManager.get_service_plugins().values())
 
     if cfg.CONF.rpc_workers < 1:
         cfg.CONF.set_override('rpc_workers', 1)
@@ -185,8 +184,8 @@ def _get_rpc_workers():
 
 
 def _get_plugins_workers():
-    # NOTE(twilson) get_service_plugins also returns the core plugin
+    # NOTE(twilson) get_plugins also returns the core plugin
-    plugins = manager.NeutronManager.get_unique_service_plugins()
+    plugins = directory.get_unique_plugins()
 
     # TODO(twilson) Instead of defaulting here, come up with a good way to
     # share a common get_workers default between NeutronPluginBaseV2 and

neutron/services/auto_allocate/db.py

@@ -14,7 +14,9 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_db import exception as db_exc
 from oslo_log import log as logging
 from sqlalchemy import sql
@@ -33,8 +35,6 @@ from neutron.db.models import external_net as ext_net_models
 from neutron.db import models_v2
 from neutron.db import standard_attr
 from neutron.extensions import l3
-from neutron import manager
-from neutron.plugins.common import constants
 from neutron.plugins.common import utils as p_utils
 from neutron.services.auto_allocate import exceptions
 from neutron.services.auto_allocate import models
@@ -101,14 +101,13 @@ class AutoAllocatedTopologyMixin(common_db_mixin.CommonDbMixin):
     @property
     def core_plugin(self):
         if not getattr(self, '_core_plugin', None):
-            self._core_plugin = manager.NeutronManager.get_plugin()
+            self._core_plugin = directory.get_plugin()
         return self._core_plugin
 
     @property
     def l3_plugin(self):
         if not getattr(self, '_l3_plugin', None):
-            self._l3_plugin = manager.NeutronManager.get_service_plugins().get(
+            self._l3_plugin = directory.get_plugin(constants.L3)
-                constants.L3_ROUTER_NAT)
         return self._l3_plugin
 
     def get_auto_allocated_topology(self, context, tenant_id, fields=None):

neutron/services/l3_router/README

@@ -10,12 +10,11 @@ The required changes to a core plugin are in that case:
   anymore.
 - Remove "router" from 'supported_extension_aliases'.
 - Modify any 'self' references to members in L3_NAT_db_mixin to instead use
-  'manager.NeutronManager.get_service_plugins().get(constants.L3_ROUTER_NAT)'
+  'directory.get_plugin(constants.L3)'
   For example,
      self.prevent_l3_port_deletion(...)
   becomes something like
-     plugin = manager.NeutronManager.get_service_plugins().get(
+     plugin = directory.get_plugin(constants.L3)
-         constants.L3_ROUTER_NAT)
      if plugin:
          plugin.prevent_l3_port_deletion(...)
 

neutron/services/l3_router/service_providers/driver_controller.py

@@ -14,6 +14,7 @@
 
 from neutron_lib import constants as lib_const
 from neutron_lib import exceptions as lib_exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 
@@ -22,7 +23,6 @@ from neutron.callbacks import events
 from neutron.callbacks import registry
 from neutron.callbacks import resources
 from neutron.db import servicetype_db as st_db
-from neutron import manager
 from neutron.plugins.common import constants
 from neutron.services import provider_configuration
 from neutron.services import service_base
@@ -64,8 +64,7 @@ class DriverController(object):
     @property
     def _flavor_plugin(self):
         if not hasattr(self, '_flavor_plugin_ref'):
-            _service_plugins = manager.NeutronManager.get_service_plugins()
+            self._flavor_plugin_ref = directory.get_plugin(constants.FLAVORS)
-            self._flavor_plugin_ref = _service_plugins[constants.FLAVORS]
         return self._flavor_plugin_ref
 
     def _set_router_provider(self, resource, event, trigger, context, router,

neutron/services/segments/db.py

@@ -19,6 +19,7 @@ import functools
 
 from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_db import exception as db_exc
 from oslo_log import helpers as log_helpers
 from oslo_utils import uuidutils
@@ -286,7 +287,7 @@ def _add_segment_host_mapping_for_segment(resource, event, trigger,
 
     if not segment.physical_network:
         return
-    cp = manager.NeutronManager.get_plugin()
+    cp = directory.get_plugin()
     check_segment_for_agent = getattr(cp, 'check_segment_for_agent', None)
     if not hasattr(cp, 'get_agents') or not check_segment_for_agent:
         # not an agent-supporting plugin

neutron/services/segments/plugin.py

@@ -14,6 +14,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.plugins import directory
+
 from neutron._i18n import _
 from neutron.api.v2 import attributes
 from neutron.callbacks import events
@@ -24,13 +26,12 @@ from neutron.db import models_v2
 from neutron.extensions import ip_allocation
 from neutron.extensions import l2_adjacency
 from neutron.extensions import segment
-from neutron import manager
 from neutron.services.segments import db
 from neutron.services.segments import exceptions
 
 
 def _extend_network_dict_binding(plugin, network_res, network_db):
-    if not manager.NeutronManager.get_service_plugins().get('segments'):
+    if not directory.get_plugin('segments'):
         return
 
     # TODO(carl_baldwin) Make this work with service subnets when it's a thing.
@@ -44,7 +45,7 @@ def _extend_subnet_dict_binding(plugin, subnet_res, subnet_db):
 
 
 def _extend_port_dict_binding(plugin, port_res, port_db):
-    if not manager.NeutronManager.get_service_plugins().get('segments'):
+    if not directory.get_plugin('segments'):
         return
 
     value = ip_allocation.IP_ALLOCATION_IMMEDIATE

neutron/services/trunk/rpc/server.py

@@ -14,6 +14,7 @@
 
 import collections
 
+from neutron_lib.plugins import directory
 from oslo_log import helpers as log_helpers
 from oslo_log import log as logging
 import oslo_messaging
@@ -26,7 +27,6 @@ from neutron.api.rpc.handlers import resources_rpc
 from neutron.common import rpc as n_rpc
 from neutron.db import api as db_api
 from neutron.extensions import portbindings
-from neutron import manager
 from neutron.objects import trunk as trunk_objects
 from neutron.services.trunk import constants as trunk_consts
 from neutron.services.trunk import exceptions as trunk_exc
@@ -76,7 +76,7 @@ class TrunkSkeleton(object):
     @property
     def core_plugin(self):
         if not self._core_plugin:
-            self._core_plugin = manager.NeutronManager.get_plugin()
+            self._core_plugin = directory.get_plugin()
         return self._core_plugin
 
     @log_helpers.log_method_call

neutron/services/trunk/rules.py

@@ -15,11 +15,11 @@
 from neutron_lib.api import converters
 from neutron_lib.api import validators
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 
 from neutron._i18n import _
 from neutron.common import utils as n_utils
 from neutron.extensions import portbindings
-from neutron import manager
 from neutron.objects import trunk as trunk_objects
 from neutron.plugins.ml2 import driver_api as api
 from neutron.services.trunk import exceptions as trunk_exc
@@ -102,7 +102,7 @@ class TrunkPortValidator(object):
     def is_bound(self, context):
         """Return true if the port is bound, false otherwise."""
         # Validate that the given port_id does not have a port binding.
-        core_plugin = manager.NeutronManager.get_plugin()
+        core_plugin = directory.get_plugin()
         self._port = core_plugin.get_port(context, self.port_id)
         return bool(self._port.get(portbindings.HOST_ID))
 
@@ -112,7 +112,7 @@ class TrunkPortValidator(object):
             # An unbound port can be trunked, always.
             return True
 
-        trunk_plugin = manager.NeutronManager.get_service_plugins()['trunk']
+        trunk_plugin = directory.get_plugin('trunk')
         vif_type = self._port.get(portbindings.VIF_TYPE)
         binding_host = self._port.get(portbindings.HOST_ID)
 
@@ -135,7 +135,7 @@ class TrunkPortValidator(object):
 
     def check_not_in_use(self, context):
         """Raises PortInUse for ports assigned for device purposes."""
-        core_plugin = manager.NeutronManager.get_plugin()
+        core_plugin = directory.get_plugin()
         self._port = core_plugin.get_port(context, self.port_id)
         # NOTE(armax): the trunk extension itself does not make use of the
         # device_id field, because it has no reason to. If need be, this
@@ -175,7 +175,7 @@ class SubPortsValidator(object):
         If the network or port cannot be obtained, or if MTU is not defined,
         returns None.
         """
-        core_plugin = manager.NeutronManager.get_plugin()
+        core_plugin = directory.get_plugin()
 
         if not n_utils.is_extension_supported(core_plugin, 'net-mtu'):
             return

neutron/services/trunk/utils.py

@@ -12,14 +12,15 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+from neutron_lib.plugins import directory
+
 from neutron.common import utils
-from neutron import manager
 
 
 def get_agent_types_by_host(context, host):
     """Return the agent types registered on the host."""
     agent_types = []
-    core_plugin = manager.NeutronManager.get_plugin()
+    core_plugin = directory.get_plugin()
     if utils.is_extension_supported(core_plugin, 'agent'):
         agents = core_plugin.get_agents(
             context.elevated(), filters={'host': [host]})

neutron/tests/base.py

@@ -30,6 +30,7 @@ from debtcollector import moves
 import eventlet.timeout
 import fixtures
 import mock
+from neutron_lib.plugins import directory
 from oslo_concurrency.fixture import lockutils
 from oslo_config import cfg
 from oslo_messaging import conffixture as messaging_conffixture
@@ -302,6 +303,7 @@ class BaseTestCase(DietTestCase):
         self.setup_rpc_mocks()
         self.setup_config()
         self.setup_test_registry_instance()
+        self.setup_test_directory_instance()
 
         policy.init()
         self.addCleanup(policy.reset)
@@ -371,6 +373,14 @@ class BaseTestCase(DietTestCase):
         mock.patch.object(registry, '_get_callback_manager',
                           return_value=self._callback_manager).start()
 
+    def setup_test_directory_instance(self):
+        """Give a private copy of the directory to each test."""
+        # TODO(armax): switch to using a fixture to stop relying on stubbing
+        # out _get_plugin_directory directly.
+        self._plugin_directory = directory._PluginDirectory()
+        mock.patch.object(directory, '_get_plugin_directory',
+                          return_value=self._plugin_directory).start()
+
     def setup_config(self, args=None):
         """Tests that need a non-default config can override this method."""
         self.config_parse(args=args)
@@ -391,11 +401,13 @@ class BaseTestCase(DietTestCase):
         for k, v in six.iteritems(kw):
             CONF.set_override(k, v, group)
 
-    def setup_coreplugin(self, core_plugin=None):
+    def setup_coreplugin(self, core_plugin=None, load_plugins=True):
         cp = PluginFixture(core_plugin)
         self.useFixture(cp)
         self.patched_dhcp_periodic = cp.patched_dhcp_periodic
         self.patched_default_svc_plugins = cp.patched_default_svc_plugins
+        if load_plugins:
+            manager.init()
 
     def setup_notification_driver(self, notification_driver=None):
         self.addCleanup(fake_notifier.reset)

neutron/tests/functional/pecan_wsgi/test_controllers.py

@@ -14,6 +14,7 @@ import uuid
 
 import mock
 from neutron_lib import constants as n_const
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_policy import policy as oslo_policy
@@ -26,7 +27,6 @@ from neutron import context
 from neutron import manager
 from neutron.pecan_wsgi.controllers import root as controllers
 from neutron.pecan_wsgi.controllers import utils as controller_utils
-from neutron.plugins.common import constants
 from neutron import policy
 from neutron.tests.common import helpers
 from neutron.tests.functional.pecan_wsgi import test_functional
@@ -56,7 +56,7 @@ class TestRootController(test_functional.PecanFunctionalTest):
     def setUp(self):
         super(TestRootController, self).setUp()
         self.setup_service_plugin()
-        self.plugin = manager.NeutronManager.get_plugin()
+        self.plugin = directory.get_plugin()
         self.ctx = context.get_admin_context()
 
     def setup_service_plugin(self):
@@ -438,7 +438,7 @@ class TestPaginationAndSorting(test_functional.PecanFunctionalTest):
         cfg.CONF.set_override('allow_pagination', True)
         cfg.CONF.set_override('allow_sorting', True)
         super(TestPaginationAndSorting, self).setUp()
-        self.plugin = manager.NeutronManager.get_plugin()
+        self.plugin = directory.get_plugin()
         self.ctx = context.get_admin_context()
         self._create_networks(self.RESOURCE_COUNT)
         self.networks = self._get_collection()['networks']
@@ -658,7 +658,7 @@ class TestRequestProcessing(TestRootController):
         self.assertEqual('router', self.req_stash['resource_type'])
         # make sure the core plugin was identified as the handler for ports
         self.assertEqual(
-            manager.NeutronManager.get_service_plugins()['L3_ROUTER_NAT'],
+            directory.get_plugin(n_const.L3),
             self.req_stash['plugin'])
 
     def test_service_plugin_uri(self):
@@ -684,10 +684,9 @@ class TestRouterController(TestResourceController):
             ['neutron.services.l3_router.l3_router_plugin.L3RouterPlugin',
              'neutron.services.flavors.flavors_plugin.FlavorsPlugin'])
         super(TestRouterController, self).setUp()
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.get_admin_context()
-        service_plugins = manager.NeutronManager.get_service_plugins()
+        l3_plugin = directory.get_plugin(n_const.L3)
-        l3_plugin = service_plugins[constants.L3_ROUTER_NAT]
         network_id = pecan_utils.create_network(ctx, plugin)['id']
         self.subnet = pecan_utils.create_subnet(ctx, plugin, network_id)
         self.router = pecan_utils.create_router(ctx, l3_plugin)
@@ -734,7 +733,7 @@ class TestDHCPAgentShimControllers(test_functional.PecanFunctionalTest):
                  'create_dhcp-networks': 'role:admin',
                  'delete_dhcp-networks': 'role:admin'}),
             overwrite=False)
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.get_admin_context()
         self.network = pecan_utils.create_network(ctx, plugin)
         self.agent = helpers.register_dhcp_agent()
@@ -788,8 +787,7 @@ class TestL3AgentShimControllers(test_functional.PecanFunctionalTest):
                  'get_l3-routers': 'role:admin'}),
             overwrite=False)
         ctx = context.get_admin_context()
-        service_plugins = manager.NeutronManager.get_service_plugins()
+        l3_plugin = directory.get_plugin(n_const.L3)
-        l3_plugin = service_plugins[constants.L3_ROUTER_NAT]
         self.router = pecan_utils.create_router(ctx, l3_plugin)
         self.agent = helpers.register_l3_agent()
         # NOTE(blogan): Not sending notifications because this test is for

neutron/tests/functional/pecan_wsgi/test_functional.py

@@ -24,17 +24,19 @@ from pecan.testing import load_test_app
 import testtools
 
 from neutron.api import extensions as exts
+from neutron import manager
 from neutron.tests.unit import testlib_api
 
 
 class PecanFunctionalTest(testlib_api.SqlTestCase):
 
     def setUp(self, service_plugins=None, extensions=None):
-        self.setup_coreplugin('ml2')
+        self.setup_coreplugin('ml2', load_plugins=False)
         super(PecanFunctionalTest, self).setUp()
         self.addCleanup(exts.PluginAwareExtensionManager.clear_instance)
         self.addCleanup(set_config, {}, overwrite=True)
         self.set_config_overrides()
+        manager.init()
         ext_mgr = exts.PluginAwareExtensionManager.get_instance()
         if extensions:
             ext_mgr.extensions = extensions

neutron/tests/functional/pecan_wsgi/test_hooks.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 import mock
+from neutron_lib.plugins import directory
 from oslo_policy import policy as oslo_policy
 from oslo_serialization import jsonutils
 
@@ -283,7 +284,7 @@ class TestMetricsNotifierHook(test_functional.PecanFunctionalTest):
     def test_bad_create_doesnt_emit_end(self):
         req_headers = {'X-Project-Id': 'tenid', 'X-Roles': 'admin'}
         payload = {'network': {'name': 'meh'}}
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         with mock.patch.object(plugin, 'create_network',
                                side_effect=ValueError):
             response = self.app.post_json(
@@ -305,7 +306,7 @@ class TestMetricsNotifierHook(test_functional.PecanFunctionalTest):
         self.assertEqual(201, response.status_int)
         json_body = jsonutils.loads(response.body)
         self.mock_notifier.reset_mock()
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         with mock.patch.object(plugin, 'update_network',
                                side_effect=ValueError):
             response = self.app.put_json(
@@ -327,7 +328,7 @@ class TestMetricsNotifierHook(test_functional.PecanFunctionalTest):
         self.assertEqual(201, response.status_int)
         json_body = jsonutils.loads(response.body)
         self.mock_notifier.reset_mock()
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         with mock.patch.object(plugin, 'delete_network',
                                side_effect=ValueError):
             response = self.app.delete(

neutron/tests/functional/test_server.py

@@ -25,6 +25,7 @@ from oslo_config import cfg
 import psutil
 
 from neutron.common import utils
+from neutron import manager
 from neutron import service
 from neutron.tests import base
 from neutron import worker as neutron_worker
@@ -223,7 +224,7 @@ class TestRPCServer(TestNeutronServer):
 
     def setUp(self):
         super(TestRPCServer, self).setUp()
-        self.setup_coreplugin('ml2')
+        self.setup_coreplugin('ml2', load_plugins=False)
         self._plugin_patcher = mock.patch(TARGET_PLUGIN, autospec=True)
         self.plugin = self._plugin_patcher.start()
         self.plugin.return_value.rpc_workers_supported = True
@@ -235,7 +236,7 @@ class TestRPCServer(TestNeutronServer):
         # receiving SIGHUP.
         with mock.patch("neutron.service.RpcWorker.start") as start_method:
             with mock.patch(
-                    "neutron.manager.NeutronManager.get_plugin"
+                    "neutron_lib.plugins.directory.get_plugin"
             ) as get_plugin:
                 start_method.side_effect = self._fake_start
                 get_plugin.return_value = self.plugin
@@ -257,12 +258,13 @@ class TestPluginWorker(TestNeutronServer):
 
     def setUp(self):
         super(TestPluginWorker, self).setUp()
-        self.setup_coreplugin('ml2')
+        self.setup_coreplugin('ml2', load_plugins=False)
         self._plugin_patcher = mock.patch(TARGET_PLUGIN, autospec=True)
         self.plugin = self._plugin_patcher.start()
+        manager.init()
 
     def _start_plugin(self, workers=1):
-        with mock.patch('neutron.manager.NeutronManager.get_plugin') as gp:
+        with mock.patch('neutron_lib.plugins.directory.get_plugin') as gp:
             gp.return_value = self.plugin
             plugin_workers_launcher = service.start_plugins_workers()
             plugin_workers_launcher.wait()

neutron/tests/retargetable/client_fixtures.py

@@ -19,6 +19,7 @@ import abc
 
 import fixtures
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 import six
 
 from neutron import context
@@ -76,6 +77,7 @@ class PluginClientFixture(AbstractClientFixture):
         self.useFixture(testlib_api.StaticSqlFixture())
         self.useFixture(self.plugin_conf)
         self.useFixture(base.PluginFixture(self.plugin_conf.plugin_name))
+        manager.init()
 
     @property
     def ctx(self):
@@ -85,7 +87,7 @@ class PluginClientFixture(AbstractClientFixture):
 
     @property
     def plugin(self):
-        return manager.NeutronManager.get_plugin()
+        return directory.get_plugin()
 
     @property
     def NotFound(self):

neutron/tests/unit/_test_extension_portbindings.py

@@ -13,13 +13,13 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from six.moves import http_client as httplib
 from webob import exc
 
 from neutron import context
 from neutron.extensions import portbindings
-from neutron import manager
 from neutron.tests.unit.db import test_db_base_plugin_v2
 
 
@@ -75,7 +75,7 @@ class PortBindingsTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
             self._check_response_no_portbindings(non_admin_port)
 
     def test_ports_vif_details(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         cfg.CONF.set_default('allow_overlapping_ips', True)
         with self.port(), self.port():
             ctx = context.get_admin_context()

neutron/tests/unit/agent/test_securitygroups_rpc.py

@@ -18,6 +18,7 @@ import contextlib
 
 import mock
 from neutron_lib import constants as const
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 import oslo_messaging
 from oslo_utils import netutils
@@ -33,7 +34,6 @@ from neutron import context
 from neutron.db import securitygroups_rpc_base as sg_db_rpc
 from neutron.extensions import allowedaddresspairs as addr_pair
 from neutron.extensions import securitygroup as ext_sg
-from neutron import manager
 from neutron.tests import base
 from neutron.tests import tools
 from neutron.tests.unit.extensions import test_securitygroup as test_sg
@@ -123,7 +123,7 @@ class SGServerRpcCallBackTestCase(test_sg.SecurityGroupDBTestCase):
         plugin = plugin or TEST_PLUGIN_CLASS
         set_firewall_driver(FIREWALL_NOOP_DRIVER)
         super(SGServerRpcCallBackTestCase, self).setUp(plugin)
-        self.notifier = manager.NeutronManager.get_plugin().notifier
+        self.notifier = directory.get_plugin().notifier
         self.rpc = securitygroups_rpc.SecurityGroupServerRpcCallback()
 
     def _test_security_group_port(self, device_owner, gw_ip,
@@ -284,7 +284,7 @@ class SGServerRpcCallBackTestCase(test_sg.SecurityGroupDBTestCase):
 
     @contextlib.contextmanager
     def _port_with_addr_pairs_and_security_group(self):
-        plugin_obj = manager.NeutronManager.get_plugin()
+        plugin_obj = directory.get_plugin()
         if ('allowed-address-pairs'
             not in plugin_obj.supported_extension_aliases):
             self.skipTest("Test depends on allowed-address-pairs extension")

neutron/tests/unit/api/rpc/agentnotifiers/test_dhcp_rpc_agent_api.py

@@ -16,6 +16,7 @@
 import datetime
 import mock
 
+from neutron_lib.plugins import directory
 from oslo_utils import timeutils
 
 from neutron.api.rpc.agentnotifiers import dhcp_rpc_agent_api
@@ -184,11 +185,10 @@ class TestDhcpAgentNotifyAPI(base.BaseTestCase):
         self.notifier.plugin.get_network.return_value = {'id': network_id}
         segment_sp = mock.Mock()
         segment_sp.get_segment.return_value = segment
-        with mock.patch('neutron.manager.NeutronManager.get_service_plugins',
+        directory.add_plugin('segments', segment_sp)
-                        return_value={'segments': segment_sp}):
+        self._test__notify_agents('subnet_create_end',
-            self._test__notify_agents('subnet_create_end',
+                                  expected_scheduling=1, expected_casts=1,
-                                      expected_scheduling=1, expected_casts=1,
+                                  payload=subnet)
-                                      payload=subnet)
         get_agents = self.notifier.plugin.get_dhcp_agents_hosting_networks
         get_agents.assert_called_once_with(
             mock.ANY, [network_id], hosts=segment['hosts'])

neutron/tests/unit/api/rpc/callbacks/test_version_manager.py

@@ -110,7 +110,7 @@ class CachedResourceConsumerTrackerTest(base.BaseTestCase):
                 tracker.set_versions(CONSUMER_1,
                                      {TEST_RESOURCE_TYPE: TEST_VERSION_A})
 
-        self.get_plugin = mock.patch('neutron.manager.NeutronManager'
+        self.get_plugin = mock.patch('neutron_lib.plugins.directory'
                                      '.get_plugin').start()
 
         self.get_plugin.return_value = _FakePlugin()

neutron/tests/unit/api/rpc/handlers/test_dhcp_rpc.py

@@ -16,6 +16,7 @@
 import mock
 from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_db import exception as db_exc
 
 from neutron.api.rpc.handlers import dhcp_rpc
@@ -32,10 +33,8 @@ class TestDhcpRpcCallback(base.BaseTestCase):
 
     def setUp(self):
         super(TestDhcpRpcCallback, self).setUp()
-        self.plugin_p = mock.patch('neutron.manager.NeutronManager.get_plugin')
-        get_plugin = self.plugin_p.start()
         self.plugin = mock.MagicMock()
-        get_plugin.return_value = self.plugin
+        directory.add_plugin(constants.CORE, self.plugin)
         self.callbacks = dhcp_rpc.DhcpRpcCallback()
         self.log_p = mock.patch('neutron.api.rpc.handlers.dhcp_rpc.LOG')
         self.log = self.log_p.start()
@@ -44,10 +43,8 @@ class TestDhcpRpcCallback(base.BaseTestCase):
         self.mock_set_dirty = set_dirty_p.start()
         self.utils_p = mock.patch('neutron.plugins.common.utils.create_port')
         self.utils = self.utils_p.start()
-        self.segment_p = mock.patch(
-            'neutron.manager.NeutronManager.get_service_plugins')
-        self.get_service_plugins = self.segment_p.start()
         self.segment_plugin = mock.MagicMock()
+        directory.add_plugin('segments', self.segment_plugin)
 
     def test_group_by_network_id(self):
         port1 = {'network_id': 'a'}
@@ -72,9 +69,6 @@ class TestDhcpRpcCallback(base.BaseTestCase):
         self.assertEqual(expected, networks)
 
     def test_get_active_networks_info_with_routed_networks(self):
-        self.get_service_plugins.return_value = {
-            'segments': self.segment_plugin
-        }
         plugin_retval = [{'id': 'a'}, {'id': 'b'}]
         port = {'network_id': 'a'}
         subnets = [{'network_id': 'b', 'id': 'c', 'segment_id': '1'},
@@ -213,22 +207,13 @@ class TestDhcpRpcCallback(base.BaseTestCase):
         self._test_get_network_info()
 
     def test_get_network_info_with_routed_network(self):
-        self.get_service_plugins.return_value = {
-            'segments': self.segment_plugin
-        }
         self._test_get_network_info(segmented_network=True,
                                     routed_network=True)
 
     def test_get_network_info_with_segmented_network_but_not_routed(self):
-        self.get_service_plugins.return_value = {
-            'segments': self.segment_plugin
-        }
         self._test_get_network_info(segmented_network=True)
 
     def test_get_network_info_with_non_segmented_network(self):
-        self.get_service_plugins.return_value = {
-            'segments': self.segment_plugin
-        }
         self._test_get_network_info()
 
     def test_update_dhcp_port_verify_port_action_port_dict(self):

neutron/tests/unit/api/rpc/handlers/test_l3_rpc.py

@@ -14,11 +14,11 @@
 # limitations under the License.
 
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 
 from neutron.api.rpc.handlers import l3_rpc
 from neutron import context
-from neutron import manager
 from neutron.tests.unit.db import test_db_base_plugin_v2
 from neutron.tests.unit import testlib_api
 
@@ -28,7 +28,7 @@ class TestL3RpcCallback(testlib_api.SqlTestCase):
     def setUp(self):
         super(TestL3RpcCallback, self).setUp()
         self.setup_coreplugin(test_db_base_plugin_v2.DB_PLUGIN_KLASS)
-        self.plugin = manager.NeutronManager.get_plugin()
+        self.plugin = directory.get_plugin()
         self.ctx = context.get_admin_context()
         cfg.CONF.set_override('ipv6_pd_enabled', True)
         self.callbacks = l3_rpc.L3RpcCallback()

neutron/tests/unit/api/test_extensions.py

@@ -18,6 +18,7 @@ import copy
 
 import fixtures
 import mock
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_log import log as logging
 from oslo_serialization import jsonutils
@@ -34,7 +35,6 @@ from neutron.api import extensions
 from neutron.api.v2 import attributes
 from neutron.common import config
 from neutron.common import exceptions
-from neutron import manager
 from neutron.plugins.common import constants
 from neutron import quota
 from neutron.tests import base
@@ -1004,7 +1004,7 @@ class ExtensionExtendedAttributeTestCase(base.BaseTestCase):
         # the global attribute map
         attributes.RESOURCE_ATTRIBUTE_MAP.update(
             extattr.EXTENDED_ATTRIBUTES_2_0)
-        self.agentscheduler_dbMinxin = manager.NeutronManager.get_plugin()
+        self.agentscheduler_dbMinxin = directory.get_plugin()
         self.addCleanup(self.restore_attribute_map)
 
         quota.QUOTAS._driver = None

neutron/tests/unit/api/v2/test_base.py

@@ -19,6 +19,7 @@ import mock
 from neutron_lib.api import converters
 from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_policy import policy as oslo_policy
@@ -36,7 +37,6 @@ from neutron.api.v2 import base as v2_base
 from neutron.api.v2 import router
 from neutron.callbacks import registry
 from neutron import context
-from neutron import manager
 from neutron import policy
 from neutron import quota
 from neutron.quota import resource_registry
@@ -101,7 +101,7 @@ class APIv2TestBase(base.BaseTestCase):
         # Create the default configurations
         self.config_parse()
         # Update the plugin
-        self.setup_coreplugin(plugin)
+        self.setup_coreplugin(plugin, load_plugins=False)
         cfg.CONF.set_override('allow_pagination', True)
         cfg.CONF.set_override('allow_sorting', True)
         self._plugin_patcher = mock.patch(plugin, autospec=True)
@@ -1160,7 +1160,7 @@ class SubresourceTest(base.BaseTestCase):
         self.useFixture(tools.AttributeMapMemento())
 
         self.config_parse()
-        self.setup_coreplugin(plugin)
+        self.setup_coreplugin(plugin, load_plugins=False)
 
         self._plugin_patcher = mock.patch(plugin, autospec=True)
         self.plugin = self._plugin_patcher.start()
@@ -1188,7 +1188,7 @@ class SubresourceTest(base.BaseTestCase):
         parent = SUB_RESOURCES['dummy'].get('parent')
         params = RESOURCE_ATTRIBUTE_MAP['dummies']
         member_actions = {'mactions': 'GET'}
-        _plugin = manager.NeutronManager.get_plugin()
+        _plugin = directory.get_plugin()
         controller = v2_base.create_resource(collection_name, resource_name,
                                              _plugin, params,
                                              member_actions=member_actions,
@@ -1492,15 +1492,14 @@ class ExtensionTestCase(base.BaseTestCase):
         self.config_parse()
 
         # Update the plugin and extensions path
-        self.setup_coreplugin(plugin)
+        self.setup_coreplugin(plugin, load_plugins=False)
         cfg.CONF.set_override('api_extensions_path', EXTDIR)
 
         self._plugin_patcher = mock.patch(plugin, autospec=True)
         self.plugin = self._plugin_patcher.start()
 
         # Instantiate mock plugin and enable the V2attributes extension
-        manager.NeutronManager.get_plugin().supported_extension_aliases = (
+        self.plugin.return_value.supported_extension_aliases = ["v2attrs"]
-            ["v2attrs"])
 
         api = router.APIRouter()
         self.api = webtest.TestApp(api)

neutron/tests/unit/core_extensions/test_qos.py

@@ -48,7 +48,7 @@ class QosCoreResourceExtensionTestCase(base.BaseTestCase):
         plugins = {}
         if plugin_loaded:
             plugins[plugin_constants.QOS] = None
-        return mock.patch('neutron.manager.NeutronManager.get_service_plugins',
+        return mock.patch('neutron_lib.plugins.directory.get_plugins',
                           return_value=plugins)
 
     def test_process_fields_no_qos_plugin_loaded(self):

neutron/tests/unit/db/test_agentschedulers_db.py

@@ -17,6 +17,7 @@ import datetime
 
 import mock
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 import oslo_messaging
@@ -37,8 +38,6 @@ from neutron.db.models import l3agent as rb_model
 from neutron.extensions import agent
 from neutron.extensions import dhcpagentscheduler
 from neutron.extensions import l3agentscheduler
-from neutron import manager
-from neutron.plugins.common import constants as service_constants
 from neutron.tests.common import helpers
 from neutron.tests import fake_notifier
 from neutron.tests import tools
@@ -257,8 +256,7 @@ class OvsAgentSchedulerTestCaseBase(test_l3.L3NatTestCaseMixin,
         # the global attribute map
         attributes.RESOURCE_ATTRIBUTE_MAP.update(
             agent.RESOURCE_ATTRIBUTE_MAP)
-        self.l3plugin = manager.NeutronManager.get_service_plugins().get(
+        self.l3plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         self.l3_notify_p = mock.patch(
             'neutron.extensions.l3agentscheduler.notify')
         self.patched_l3_notify = self.l3_notify_p.start()
@@ -531,7 +529,7 @@ class OvsAgentSchedulerTestCase(OvsAgentSchedulerTestCaseBase):
             self.assertEqual(0, len(dhcp_agents['agents']))
 
     def test_network_scheduler_with_hosted_network(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         helpers.register_dhcp_agent(DHCP_HOSTA)
         with self.port() as port1:
             dhcp_agents = self._list_dhcp_agents_hosting_network(
@@ -619,7 +617,7 @@ class OvsAgentSchedulerTestCase(OvsAgentSchedulerTestCaseBase):
         self.assertEqual(0, num_after_remove)
 
     def test_list_active_networks_on_not_registered_yet_dhcp_agent(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         nets = plugin.list_active_networks_on_active_dhcp_agent(
             self.adminContext, host=DHCP_HOSTA)
         self.assertEqual([], nets)
@@ -674,9 +672,7 @@ class OvsAgentSchedulerTestCase(OvsAgentSchedulerTestCaseBase):
             agt.heartbeat_timestamp - datetime.timedelta(hours=1))
         self.adminContext.session.commit()
 
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
-
         plugin.reschedule_routers_from_down_agents()
 
     def _set_agent_admin_state_up(self, host, state):
@@ -693,8 +689,7 @@ class OvsAgentSchedulerTestCase(OvsAgentSchedulerTestCaseBase):
             # schedule the router to host A
             l3_rpc_cb.get_router_ids(self.adminContext, host=L3_HOSTA)
 
-            plugin = manager.NeutronManager.get_service_plugins().get(
+            plugin = directory.get_plugin(constants.L3)
-                service_constants.L3_ROUTER_NAT)
             mock.patch.object(
                 plugin, 'reschedule_router',
                 side_effect=[
@@ -715,14 +710,12 @@ class OvsAgentSchedulerTestCase(OvsAgentSchedulerTestCaseBase):
             mock_ctx = mock.Mock()
             get_ctx.return_value = mock_ctx
             mock_ctx.session.query.side_effect = db_exc.DBError()
-            plugin = manager.NeutronManager.get_service_plugins().get(
+            plugin = directory.get_plugin(constants.L3)
-                service_constants.L3_ROUTER_NAT)
             # check that no exception is raised
             plugin.reschedule_routers_from_down_agents()
 
     def test_router_rescheduler_iterates_after_reschedule_failure(self):
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         l3_rpc_cb = l3_rpc.L3RpcCallback()
         self._register_agent_states()
         with self.router() as r1, self.router() as r2:
@@ -754,8 +747,7 @@ class OvsAgentSchedulerTestCase(OvsAgentSchedulerTestCaseBase):
                 self.assertFalse(rr.called)
 
     def test_router_is_not_rescheduled_if_agent_is_back_online(self):
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(constants.L3)
-            service_constants.L3_ROUTER_NAT)
         l3_rpc_cb = l3_rpc.L3RpcCallback()
         agent = helpers.register_l3_agent(host=L3_HOSTA)
         with self.router(),\
@@ -1301,7 +1293,7 @@ class OvsDhcpAgentNotifierTestCase(test_agent.AgentDBTestMixIn,
         mock.patch.object(
             self.plugin, 'filter_hosts_with_network_access',
             side_effect=lambda context, network_id, hosts: hosts).start()
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         self.dhcp_notifier = plugin.agent_notifiers[constants.AGENT_TYPE_DHCP]
         self.dhcp_notifier_cast = mock.patch(
             'neutron.api.rpc.agentnotifiers.dhcp_rpc_agent_api.'
@@ -1434,7 +1426,7 @@ class OvsDhcpAgentNotifierTestCase(test_agent.AgentDBTestMixIn,
         dhcp_notifier_schedule = mock.patch(
             'neutron.api.rpc.agentnotifiers.dhcp_rpc_agent_api.'
             'DhcpAgentNotifyAPI._schedule_network').start()
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         with self.subnet() as subnet,\
                 self.port(subnet=subnet, device_id=device_id),\
                 mock.patch.object(plugin,
@@ -1490,8 +1482,7 @@ class OvsL3AgentNotifierTestCase(test_l3.L3NatTestCaseMixin,
         fake_notifier.reset()
 
     def test_router_add_to_l3_agent_notification(self):
-        l3_plugin = (manager.NeutronManager.get_service_plugins()
+        l3_plugin = directory.get_plugin(constants.L3)
-                     [service_constants.L3_ROUTER_NAT])
         l3_notifier = l3_plugin.agent_notifiers[constants.AGENT_TYPE_L3]
         with mock.patch.object(
             l3_notifier.client,
@@ -1513,8 +1504,7 @@ class OvsL3AgentNotifierTestCase(test_l3.L3NatTestCaseMixin,
             self._assert_notify(notifications, expected_event_type)
 
     def test_router_remove_from_l3_agent_notification(self):
-        l3_plugin = (manager.NeutronManager.get_service_plugins()
+        l3_plugin = directory.get_plugin(constants.L3)
-                     [service_constants.L3_ROUTER_NAT])
         l3_notifier = l3_plugin.agent_notifiers[constants.AGENT_TYPE_L3]
         with mock.patch.object(
             l3_notifier.client,
@@ -1539,8 +1529,7 @@ class OvsL3AgentNotifierTestCase(test_l3.L3NatTestCaseMixin,
             self._assert_notify(notifications, expected_event_type)
 
     def test_agent_updated_l3_agent_notification(self):
-        l3_plugin = (manager.NeutronManager.get_service_plugins()
+        l3_plugin = directory.get_plugin(constants.L3)
-                     [service_constants.L3_ROUTER_NAT])
         l3_notifier = l3_plugin.agent_notifiers[constants.AGENT_TYPE_L3]
         with mock.patch.object(
             l3_notifier.client,

neutron/tests/unit/db/test_allowedaddresspairs_db.py

@@ -14,6 +14,7 @@
 # limitations under the License.
 
 from neutron_lib.api import validators
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from webob import exc as web_exc
 
@@ -23,7 +24,6 @@ from neutron.db import portsecurity_db
 from neutron.extensions import allowedaddresspairs as addr_pair
 from neutron.extensions import portsecurity as psec
 from neutron.extensions import securitygroup as secgroup
-from neutron import manager
 from neutron.tests.unit.db import test_db_base_plugin_v2
 
 
@@ -37,7 +37,7 @@ class AllowedAddressPairTestCase(
         super(AllowedAddressPairTestCase, self).setUp(plugin)
 
         # Check if a plugin supports security groups
-        plugin_obj = manager.NeutronManager.get_plugin()
+        plugin_obj = directory.get_plugin()
         self._skip_port_security = ('port-security' not in
                                     plugin_obj.supported_extension_aliases)
 

neutron/tests/unit/db/test_db_base_plugin_v2.py

@@ -23,6 +23,7 @@ import mock
 import netaddr
 from neutron_lib import constants
 from neutron_lib import exceptions as lib_exc
+from neutron_lib.plugins import directory
 from neutron_lib.utils import helpers
 from oslo_concurrency import lockutils
 from oslo_config import cfg
@@ -56,7 +57,6 @@ from neutron.db.models import securitygroup as sg_models
 from neutron.db import models_v2
 from neutron.db import standard_attr
 from neutron.ipam import exceptions as ipam_exc
-from neutron import manager
 from neutron.tests import base
 from neutron.tests import tools
 from neutron.tests.unit.api import test_extensions
@@ -93,7 +93,7 @@ def _fake_get_sorting_helper(self, request):
 # instead of directly using NeutronDbPluginV2TestCase
 def _get_create_db_method(resource):
     ml2_method = '_create_%s_db' % resource
-    if hasattr(manager.NeutronManager.get_plugin(), ml2_method):
+    if hasattr(directory.get_plugin(), ml2_method):
         return ml2_method
     else:
         return 'create_%s' % resource
@@ -120,7 +120,7 @@ class NeutronDbPluginV2TestCase(testlib_api.WebTestCase):
             plugin = DB_PLUGIN_KLASS
 
         # Update the plugin
-        self.setup_coreplugin(plugin)
+        self.setup_coreplugin(plugin, load_plugins=False)
         cfg.CONF.set_override(
             'service_plugins',
             [test_lib.test_config.get(key, default)
@@ -138,7 +138,7 @@ class NeutronDbPluginV2TestCase(testlib_api.WebTestCase):
         self.port_create_status = 'ACTIVE'
 
         def _is_native_bulk_supported():
-            plugin_obj = manager.NeutronManager.get_plugin()
+            plugin_obj = directory.get_plugin()
             native_bulk_attr_name = ("_%s__native_bulk_support"
                                      % plugin_obj.__class__.__name__)
             return getattr(plugin_obj, native_bulk_attr_name, False)
@@ -148,9 +148,9 @@ class NeutronDbPluginV2TestCase(testlib_api.WebTestCase):
         def _is_native_pagination_support():
             native_pagination_attr_name = (
                 "_%s__native_pagination_support" %
-                manager.NeutronManager.get_plugin().__class__.__name__)
+                directory.get_plugin().__class__.__name__)
             return (cfg.CONF.allow_pagination and
-                    getattr(manager.NeutronManager.get_plugin(),
+                    getattr(directory.get_plugin(),
                             native_pagination_attr_name, False))
 
         self._skip_native_pagination = not _is_native_pagination_support()
@@ -158,12 +158,12 @@ class NeutronDbPluginV2TestCase(testlib_api.WebTestCase):
         def _is_native_sorting_support():
             native_sorting_attr_name = (
                 "_%s__native_sorting_support" %
-                manager.NeutronManager.get_plugin().__class__.__name__)
+                directory.get_plugin().__class__.__name__)
             return (cfg.CONF.allow_sorting and
-                    getattr(manager.NeutronManager.get_plugin(),
+                    getattr(directory.get_plugin(),
                             native_sorting_attr_name, False))
 
-        self.plugin = manager.NeutronManager.get_plugin()
+        self.plugin = directory.get_plugin()
         self._skip_native_sorting = not _is_native_sorting_support()
         if ext_mgr:
             self.ext_api = test_extensions.setup_extensions_middleware(ext_mgr)
@@ -1083,7 +1083,7 @@ class TestPortsV2(NeutronDbPluginV2TestCase):
             tenid = p['port']['tenant_id']
             ctx = context.Context(user_id=None, tenant_id=tenid,
                                   is_admin=False)
-            pl = manager.NeutronManager.get_plugin()
+            pl = directory.get_plugin()
             count = pl.get_ports_count(ctx, filters={'tenant_id': [tenid]})
             self.assertEqual(4, count)
 
@@ -1098,9 +1098,9 @@ class TestPortsV2(NeutronDbPluginV2TestCase):
 
         with mock.patch('six.moves.builtins.hasattr',
                         new=fakehasattr):
-            orig = manager.NeutronManager.get_plugin().create_port
+            orig = directory.get_plugin().create_port
             method_to_patch = _get_create_db_method('port')
-            with mock.patch.object(manager.NeutronManager.get_plugin(),
+            with mock.patch.object(directory.get_plugin(),
                                    method_to_patch) as patched_plugin:
 
                 def side_effect(*args, **kwargs):
@@ -1123,7 +1123,7 @@ class TestPortsV2(NeutronDbPluginV2TestCase):
             self.skipTest("Plugin does not support native bulk port create")
         ctx = context.get_admin_context()
         with self.network() as net:
-            plugin = manager.NeutronManager.get_plugin()
+            plugin = directory.get_plugin()
             orig = plugin.create_port
             method_to_patch = _get_create_db_method('port')
             with mock.patch.object(plugin, method_to_patch) as patched_plugin:
@@ -2443,7 +2443,7 @@ fixed_ips=ip_address%%3D%s&fixed_ips=ip_address%%3D%s&fixed_ips=subnet_id%%3D%s
                                  res.status_int)
 
     def test_delete_ports_by_device_id(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.get_admin_context()
         with self.subnet() as subnet:
             with self.port(subnet=subnet, device_id='owner1') as p1,\
@@ -2486,7 +2486,7 @@ fixed_ips=ip_address%%3D%s&fixed_ips=ip_address%%3D%s&fixed_ips=subnet_id%%3D%s
                            expected_code=webob.exc.HTTPOk.code)
 
     def test_delete_ports_by_device_id_second_call_failure(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         self._test_delete_ports_by_device_id_second_call_failure(plugin)
 
     def _test_delete_ports_ignores_port_not_found(self, plugin):
@@ -2509,7 +2509,7 @@ fixed_ips=ip_address%%3D%s&fixed_ips=ip_address%%3D%s&fixed_ips=subnet_id%%3D%s
                               "deleting some of the same ports.")
 
     def test_delete_ports_ignores_port_not_found(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         self._test_delete_ports_ignores_port_not_found(plugin)
 
 
@@ -2597,7 +2597,7 @@ class TestNetworksV2(NeutronDbPluginV2TestCase):
                 # must query db to see whether subnet's shared attribute
                 # has been updated or not
                 ctx = context.Context('', '', is_admin=True)
-                subnet_db = manager.NeutronManager.get_plugin().get_subnet(
+                subnet_db = directory.get_plugin().get_subnet(
                     ctx, subnet['subnet']['id'])
                 self.assertTrue(subnet_db['shared'])
 
@@ -2774,12 +2774,12 @@ class TestNetworksV2(NeutronDbPluginV2TestCase):
                 return False
             return real_has_attr(item, attr)
 
-        orig = manager.NeutronManager.get_plugin().create_network
+        orig = directory.get_plugin().create_network
         #ensures the API choose the emulation code path
         with mock.patch('six.moves.builtins.hasattr',
                         new=fakehasattr):
             method_to_patch = _get_create_db_method('network')
-            with mock.patch.object(manager.NeutronManager.get_plugin(),
+            with mock.patch.object(directory.get_plugin(),
                                    method_to_patch) as patched_plugin:
 
                 def side_effect(*args, **kwargs):
@@ -2796,9 +2796,9 @@ class TestNetworksV2(NeutronDbPluginV2TestCase):
     def test_create_networks_bulk_native_plugin_failure(self):
         if self._skip_native_bulk:
             self.skipTest("Plugin does not support native bulk network create")
-        orig = manager.NeutronManager.get_plugin().create_network
+        orig = directory.get_plugin().create_network
         method_to_patch = _get_create_db_method('network')
-        with mock.patch.object(manager.NeutronManager.get_plugin(),
+        with mock.patch.object(directory.get_plugin(),
                                method_to_patch) as patched_plugin:
 
             def side_effect(*args, **kwargs):
@@ -3249,9 +3249,9 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
 
         with mock.patch('six.moves.builtins.hasattr',
                         new=fakehasattr):
-            orig = manager.NeutronManager.get_plugin().create_subnet
+            orig = directory.get_plugin().create_subnet
             method_to_patch = _get_create_db_method('subnet')
-            with mock.patch.object(manager.NeutronManager.get_plugin(),
+            with mock.patch.object(directory.get_plugin(),
                                    method_to_patch) as patched_plugin:
 
                 def side_effect(*args, **kwargs):
@@ -3272,7 +3272,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
     def test_create_subnets_bulk_native_plugin_failure(self):
         if self._skip_native_bulk:
             self.skipTest("Plugin does not support native bulk subnet create")
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         orig = plugin.create_subnet
         method_to_patch = _get_create_db_method('subnet')
         with mock.patch.object(plugin, method_to_patch) as patched_plugin:
@@ -4043,7 +4043,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
 
     def _test_validate_subnet_ipv6_modes(self, cur_subnet=None,
                                          expect_success=True, **modes):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.get_admin_context()
         new_subnet = {'ip_version': 6,
                       'cidr': 'fe80::/64',
@@ -4060,7 +4060,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
 
     def _test_validate_subnet_ipv6_pd_modes(self, cur_subnet=None,
                                          expect_success=True, **modes):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.get_admin_context()
         new_subnet = {'ip_version': 6,
                       'cidr': n_const.PROVISIONAL_IPV6_PD_PREFIX,
@@ -4252,7 +4252,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
                                   '_get_subnet',
                                   return_value=v6_subnet).start()
             # Add an IPv6 auto-address subnet to the network
-            with mock.patch.object(manager.NeutronManager.get_plugin(),
+            with mock.patch.object(directory.get_plugin(),
                                    'update_port') as mock_updated_port:
                 v6_subnet = self._make_subnet(self.fmt, network, 'fe80::1',
                                               'fe80::/64', ip_version=6,
@@ -4945,7 +4945,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
                       'ip_version': 4,
                       'enable_dhcp': True,
                       'tenant_id': network['network']['tenant_id']}
-            plugin = manager.NeutronManager.get_plugin()
+            plugin = directory.get_plugin()
             if hasattr(plugin, '_validate_subnet'):
                 self.assertRaises(lib_exc.InvalidInput,
                                   plugin._validate_subnet,
@@ -5274,7 +5274,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
                       'dns_nameservers': ['8.8.8.8'],
                       'host_routes': [{'destination': '135.207.0.0/16',
                                        'nexthop': '1.2.3.4'}]}
-            plugin = manager.NeutronManager.get_plugin()
+            plugin = directory.get_plugin()
             e = self.assertRaises(exception,
                                   plugin._validate_subnet,
                                   context.get_admin_context(),
@@ -6355,7 +6355,7 @@ class NeutronDbPluginV2AsMixinTestCase(NeutronDbPluginV2TestCase,
         self.assertEqual(net['status'], 'BUILD')
 
     def test_get_user_allocation_for_dhcp_port_returns_none(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         with self.network() as net, self.network() as net1:
             with self.subnet(network=net, cidr='10.0.0.0/24') as subnet,\
                     self.subnet(network=net1, cidr='10.0.1.0/24') as subnet1:
@@ -6409,7 +6409,7 @@ class TestNetworks(testlib_api.SqlTestCase):
     def _test_update_shared_net_used(self,
                                      device_owner,
                                      expected_exception=None):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.get_admin_context()
         network, net_id = self._create_network(plugin, ctx)
 

neutron/tests/unit/db/test_dvr_mac_db.py

@@ -15,6 +15,7 @@
 
 import mock
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 
 from neutron.callbacks import events
 from neutron.callbacks import registry
@@ -24,7 +25,6 @@ from neutron.db import dvr_mac_db
 from neutron.db.models import dvr as dvr_models
 from neutron.extensions import dvr
 from neutron.extensions import portbindings
-from neutron import manager
 from neutron.tests.unit.plugins.ml2 import test_plugin
 
 
@@ -77,7 +77,7 @@ class DvrDbMixinTestCase(test_plugin.Ml2PluginV2TestCase):
                               self.ctx, "foo_host_2")
 
     def test_mac_not_cleared_on_agent_delete_event_with_remaining_agents(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         self._create_dvr_mac_entry('host_1', 'mac_1')
         self._create_dvr_mac_entry('host_2', 'mac_2')
         agent1 = {'host': 'host_1', 'id': 'a1'}
@@ -91,7 +91,7 @@ class DvrDbMixinTestCase(test_plugin.Ml2PluginV2TestCase):
         self.assertFalse(notifier.dvr_mac_address_update.called)
 
     def test_mac_cleared_on_agent_delete_event(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         self._create_dvr_mac_entry('host_1', 'mac_1')
         self._create_dvr_mac_entry('host_2', 'mac_2')
         agent = {'host': 'host_1', 'id': 'a1'}

neutron/tests/unit/db/test_l3_db.py

@@ -16,6 +16,7 @@
 import mock
 from neutron_lib import constants as n_const
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 import testtools
 
 from neutron.callbacks import events
@@ -24,7 +25,6 @@ from neutron.callbacks import resources
 from neutron.db import l3_db
 from neutron.db.models import l3 as l3_models
 from neutron.extensions import l3
-from neutron import manager
 from neutron.tests import base
 
 
@@ -49,7 +49,7 @@ class TestL3_NAT_dbonly_mixin(base.BaseTestCase):
     def test__get_subnets_by_network_no_query(self):
         """Basic test that no query is performed if no Ports are passed"""
         context = mock.Mock()
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as get_p:
+        with mock.patch.object(directory, 'get_plugin') as get_p:
             self.db._get_subnets_by_network_list(context, [])
         self.assertFalse(context.session.query.called)
         self.assertFalse(get_p.called)
@@ -61,7 +61,7 @@ class TestL3_NAT_dbonly_mixin(base.BaseTestCase):
         query.__iter__.return_value = [(mock.sentinel.subnet_db,
                                         mock.sentinel.address_scope_id)]
 
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as get_p:
+        with mock.patch.object(directory, 'get_plugin') as get_p:
             get_p()._make_subnet_dict.return_value = {
                 'network_id': mock.sentinel.network_id}
             subnets = self.db._get_subnets_by_network_list(
@@ -74,7 +74,7 @@ class TestL3_NAT_dbonly_mixin(base.BaseTestCase):
     def test__populate_ports_for_subnets_none(self):
         """Basic test that the method runs correctly with no ports"""
         ports = []
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as get_p:
+        with mock.patch.object(directory, 'get_plugin') as get_p:
             get_p().get_networks.return_value = []
             self.db._populate_mtu_and_subnets_for_ports(mock.sentinel.context,
                                                         ports)
@@ -96,7 +96,7 @@ class TestL3_NAT_dbonly_mixin(base.BaseTestCase):
         ports = [{'network_id': 'net_id',
                   'id': 'port_id',
                   'fixed_ips': [{'subnet_id': mock.sentinel.subnet_id}]}]
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as get_p:
+        with mock.patch.object(directory, 'get_plugin') as get_p:
             get_p().get_networks.return_value = [{'id': 'net_id', 'mtu': 1446}]
             self.db._populate_mtu_and_subnets_for_ports(mock.sentinel.context,
                                                         ports)
@@ -147,19 +147,19 @@ class TestL3_NAT_dbonly_mixin(base.BaseTestCase):
                           ({'id': 'id2'}, 'scope2'),
                           ({'id': 'id3'}, 'scope3')], result)
 
-    @mock.patch.object(manager.NeutronManager, 'get_plugin')
+    @mock.patch.object(directory, 'get_plugin')
     def test_prevent_l3_port_deletion_port_not_found(self, gp):
         # port not found doesn't prevent
         gp.return_value.get_port.side_effect = n_exc.PortNotFound(port_id='1')
         self.db.prevent_l3_port_deletion(None, None)
 
-    @mock.patch.object(manager.NeutronManager, 'get_plugin')
+    @mock.patch.object(directory, 'get_plugin')
     def test_prevent_l3_port_device_owner_not_router(self, gp):
         # ignores other device owners
         gp.return_value.get_port.return_value = {'device_owner': 'cat'}
         self.db.prevent_l3_port_deletion(None, None)
 
-    @mock.patch.object(manager.NeutronManager, 'get_plugin')
+    @mock.patch.object(directory, 'get_plugin')
     def test_prevent_l3_port_no_fixed_ips(self, gp):
         # without fixed IPs is allowed
         gp.return_value.get_port.return_value = {
@@ -168,7 +168,7 @@ class TestL3_NAT_dbonly_mixin(base.BaseTestCase):
         }
         self.db.prevent_l3_port_deletion(None, None)
 
-    @mock.patch.object(manager.NeutronManager, 'get_plugin')
+    @mock.patch.object(directory, 'get_plugin')
     def test_prevent_l3_port_no_router(self, gp):
         # without router is allowed
         gp.return_value.get_port.return_value = {
@@ -179,7 +179,7 @@ class TestL3_NAT_dbonly_mixin(base.BaseTestCase):
         self.db.get_router.side_effect = l3.RouterNotFound(router_id='44')
         self.db.prevent_l3_port_deletion(mock.Mock(), None)
 
-    @mock.patch.object(manager.NeutronManager, 'get_plugin')
+    @mock.patch.object(directory, 'get_plugin')
     def test_prevent_l3_port_existing_router(self, gp):
         gp.return_value.get_port.return_value = {
             'device_owner': n_const.DEVICE_OWNER_ROUTER_INTF,
@@ -189,7 +189,7 @@ class TestL3_NAT_dbonly_mixin(base.BaseTestCase):
         with testtools.ExpectedException(n_exc.ServicePortInUse):
             self.db.prevent_l3_port_deletion(mock.Mock(), None)
 
-    @mock.patch.object(manager.NeutronManager, 'get_plugin')
+    @mock.patch.object(directory, 'get_plugin')
     def test_prevent_l3_port_existing_floating_ip(self, gp):
         gp.return_value.get_port.return_value = {
             'device_owner': n_const.DEVICE_OWNER_FLOATINGIP,

neutron/tests/unit/db/test_l3_dvr_db.py

@@ -14,8 +14,9 @@
 # limitations under the License.
 
 import mock
-from neutron_lib import constants as l3_const
+from neutron_lib import constants as const
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_utils import uuidutils
 import testtools
 
@@ -29,8 +30,6 @@ from neutron.db import common_db_mixin
 from neutron.db import l3_agentschedulers_db
 from neutron.db import l3_dvr_db
 from neutron.extensions import portbindings
-from neutron import manager
-from neutron.plugins.common import constants as plugin_const
 from neutron.tests.unit.db import test_db_base_plugin_v2
 
 _uuid = uuidutils.generate_uuid
@@ -47,7 +46,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
 
     def setUp(self):
         super(L3DvrTestCase, self).setUp(plugin='ml2')
-        self.core_plugin = manager.NeutronManager.get_plugin()
+        self.core_plugin = directory.get_plugin()
         self.ctx = context.get_admin_context()
         self.mixin = FakeL3Plugin()
 
@@ -125,7 +124,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
                          self.mixin._update_distributed_attr.call_count)
 
     def _test_get_device_owner(self, is_distributed=False,
-                               expected=l3_const.DEVICE_OWNER_ROUTER_INTF,
+                               expected=const.DEVICE_OWNER_ROUTER_INTF,
                                pass_router_id=True):
         router = {
             'name': 'foo_router',
@@ -148,7 +147,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
     def test__get_device_owner_distributed(self):
         self._test_get_device_owner(
             is_distributed=True,
-            expected=l3_const.DEVICE_OWNER_DVR_INTERFACE,
+            expected=const.DEVICE_OWNER_DVR_INTERFACE,
             pass_router_id=False)
 
     def _test__is_distributed_router(self, router, expected):
@@ -173,34 +172,32 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
         self._test__is_distributed_router(router, True)
 
     def test__get_agent_gw_ports_exist_for_network(self):
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as gp:
+        plugin = mock.Mock()
-            plugin = mock.Mock()
+        directory.add_plugin(const.CORE, plugin)
-            gp.return_value = plugin
+        plugin.get_ports.return_value = []
-            plugin.get_ports.return_value = []
+        self.mixin._get_agent_gw_ports_exist_for_network(
-            self.mixin._get_agent_gw_ports_exist_for_network(
+            self.ctx, 'network_id', 'host', 'agent_id')
-                self.ctx, 'network_id', 'host', 'agent_id')
         plugin.get_ports.assert_called_with(self.ctx, {
             'network_id': ['network_id'],
             'device_id': ['agent_id'],
-            'device_owner': [l3_const.DEVICE_OWNER_AGENT_GW]})
+            'device_owner': [const.DEVICE_OWNER_AGENT_GW]})
 
     def _test_prepare_direct_delete_dvr_internal_ports(self, port):
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as gp:
+        plugin = mock.Mock()
-            plugin = mock.Mock()
+        directory.add_plugin(const.CORE, plugin)
-            gp.return_value = plugin
+        plugin.get_port.return_value = port
-            plugin.get_port.return_value = port
+        self.mixin._router_exists = mock.Mock(return_value=True)
-            self.mixin._router_exists = mock.Mock(return_value=True)
+        self.assertRaises(exceptions.ServicePortInUse,
-            self.assertRaises(exceptions.ServicePortInUse,
+                          self.mixin.prevent_l3_port_deletion,
-                              self.mixin.prevent_l3_port_deletion,
+                          self.ctx,
-                              self.ctx,
+                          port['id'])
-                              port['id'])
 
     def test_prevent_delete_floatingip_agent_gateway_port(self):
         port = {
             'id': 'my_port_id',
             'fixed_ips': mock.ANY,
             'device_id': 'r_id',
-            'device_owner': l3_const.DEVICE_OWNER_AGENT_GW
+            'device_owner': const.DEVICE_OWNER_AGENT_GW
         }
         self._test_prepare_direct_delete_dvr_internal_ports(port)
 
@@ -209,7 +206,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
             'id': 'my_port_id',
             'fixed_ips': mock.ANY,
             'device_id': 'r_id',
-            'device_owner': l3_const.DEVICE_OWNER_ROUTER_SNAT
+            'device_owner': const.DEVICE_OWNER_ROUTER_SNAT
         }
         self._test_prepare_direct_delete_dvr_internal_ports(port)
 
@@ -248,7 +245,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
     def test__port_has_ipv6_address_for_dvr_snat_port(self):
         port = {
             'id': 'my_port_id',
-            'device_owner': l3_const.DEVICE_OWNER_ROUTER_SNAT,
+            'device_owner': const.DEVICE_OWNER_ROUTER_SNAT,
         }
         result, pv6 = self.setup_port_has_ipv6_address(port)
         self.assertFalse(result)
@@ -257,7 +254,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
     def test__port_has_ipv6_address_for_non_snat_ports(self):
         port = {
             'id': 'my_port_id',
-            'device_owner': l3_const.DEVICE_OWNER_DVR_INTERFACE,
+            'device_owner': const.DEVICE_OWNER_DVR_INTERFACE,
         }
         result, pv6 = self.setup_port_has_ipv6_address(port)
         self.assertTrue(result)
@@ -268,23 +265,22 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
             'id': 'my_port_id',
             portbindings.HOST_ID: 'foo_host',
             'network_id': 'ext_network_id',
-            'device_owner': l3_const.DEVICE_OWNER_ROUTER_GW
+            'device_owner': const.DEVICE_OWNER_ROUTER_GW
         },
                 {
             'id': 'my_new_port_id',
             portbindings.HOST_ID: 'my_foo_host',
             'network_id': 'ext_network_id',
-            'device_owner': l3_const.DEVICE_OWNER_ROUTER_GW
+            'device_owner': const.DEVICE_OWNER_ROUTER_GW
         }]
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as gp:
+        plugin = mock.Mock()
-            plugin = mock.Mock()
+        directory.add_plugin(const.CORE, plugin)
-            gp.return_value = plugin
+        plugin.get_ports.return_value = ports
-            plugin.get_ports.return_value = ports
+        self.mixin.delete_floatingip_agent_gateway_port(
-            self.mixin.delete_floatingip_agent_gateway_port(
+            self.ctx, port_host, 'ext_network_id')
-                self.ctx, port_host, 'ext_network_id')
         plugin.get_ports.assert_called_with(self.ctx, filters={
             'network_id': ['ext_network_id'],
-            'device_owner': [l3_const.DEVICE_OWNER_AGENT_GW]})
+            'device_owner': [const.DEVICE_OWNER_AGENT_GW]})
         if port_host:
             plugin.ipam.delete_port.assert_called_once_with(
                 self.ctx, 'my_port_id')
@@ -307,15 +303,16 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
             gw_port_db = {
                 'id': 'my_gw_id',
                 'network_id': 'ext_net_id',
-                'device_owner': l3_const.DEVICE_OWNER_ROUTER_GW
+                'device_owner': const.DEVICE_OWNER_ROUTER_GW
             }
             router.gw_port = gw_port_db
         else:
             router.gw_port = None
 
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as gp,\
+        plugin = mock.Mock()
-            mock.patch.object(l3_dvr_db.l3_db.L3_NAT_db_mixin,
+        directory.add_plugin(const.CORE, plugin)
-                              '_delete_current_gw_port'),\
+        with mock.patch.object(l3_dvr_db.l3_db.L3_NAT_db_mixin,
+                               '_delete_current_gw_port'),\
             mock.patch.object(
                 self.mixin,
                 '_get_router') as grtr,\
@@ -328,8 +325,6 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
             mock.patch.object(
                 self.mixin.l3_rpc_notifier,
                 'delete_fipnamespace_for_ext_net') as del_fip:
-            plugin = mock.Mock()
-            gp.return_value = plugin
             plugin.get_ports.return_value = port
             grtr.return_value = router
             self.mixin._delete_current_gw_port(
@@ -351,12 +346,12 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
         port = [{
             'id': 'my_port_id',
             'network_id': 'ext_net_id',
-            'device_owner': l3_const.DEVICE_OWNER_ROUTER_GW
+            'device_owner': const.DEVICE_OWNER_ROUTER_GW
         },
                 {
             'id': 'my_new_port_id',
             'network_id': 'ext_net_id',
-            'device_owner': l3_const.DEVICE_OWNER_ROUTER_GW
+            'device_owner': const.DEVICE_OWNER_ROUTER_GW
         }]
         rtr, plugin, d_csnat_port, d_agent_gw_port, del_fip = (
             self._setup_delete_current_gw_port_deletes_fip_agent_gw_port(
@@ -411,7 +406,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
     def test_floatingip_on_port_not_host(self):
         router, fip = self._floatingip_on_port_test_setup(None)
 
-        self.assertNotIn(l3_const.FLOATINGIP_KEY, router)
+        self.assertNotIn(const.FLOATINGIP_KEY, router)
         self.assertNotIn(n_const.FLOATINGIP_AGENT_INTF_KEY, router)
 
     def test_floatingip_on_port_with_host(self):
@@ -419,9 +414,9 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
 
         self.assertTrue(self.mixin._get_fip_sync_interfaces.called)
 
-        self.assertIn(l3_const.FLOATINGIP_KEY, router)
+        self.assertIn(const.FLOATINGIP_KEY, router)
         self.assertIn(n_const.FLOATINGIP_AGENT_INTF_KEY, router)
-        self.assertIn(fip, router[l3_const.FLOATINGIP_KEY])
+        self.assertIn(fip, router[const.FLOATINGIP_KEY])
         self.assertIn('fip_interface',
             router[n_const.FLOATINGIP_AGENT_INTF_KEY])
 
@@ -509,24 +504,20 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
                 {'subnet_id': subnet2['subnet']['id']})
 
             csnat_filters = {'device_owner':
-                             [l3_const.DEVICE_OWNER_ROUTER_SNAT]}
+                             [const.DEVICE_OWNER_ROUTER_SNAT]}
             csnat_ports = self.core_plugin.get_ports(
                 self.ctx, filters=csnat_filters)
             self.assertEqual(2, len(csnat_ports))
 
             dvr_filters = {'device_owner':
-                           [l3_const.DEVICE_OWNER_DVR_INTERFACE]}
+                           [const.DEVICE_OWNER_DVR_INTERFACE]}
             dvr_ports = self.core_plugin.get_ports(
                 self.ctx, filters=dvr_filters)
             self.assertEqual(2, len(dvr_ports))
 
-            with mock.patch.object(manager.NeutronManager,
+            directory.add_plugin(const.L3, plugin)
-                                  'get_service_plugins') as get_svc_plugin:
+            self.mixin.remove_router_interface(
-                get_svc_plugin.return_value = {
+                self.ctx, router['id'], {'port_id': dvr_ports[0]['id']})
-                    plugin_const.L3_ROUTER_NAT: plugin}
-                self.mixin.manager = manager
-                self.mixin.remove_router_interface(
-                    self.ctx, router['id'], {'port_id': dvr_ports[0]['id']})
 
             csnat_ports = self.core_plugin.get_ports(
                 self.ctx, filters=csnat_filters)
@@ -561,11 +552,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
                     {'subnet_id': subnet_v4['subnet']['id']})
                 self.mixin.add_router_interface(self.ctx, router['id'],
                     {'subnet_id': subnet_v6['subnet']['id']})
-                get_svc_plugin = mock.patch.object(
+                directory.add_plugin(const.L3, plugin)
-                    manager.NeutronManager, 'get_service_plugins').start()
-                get_svc_plugin.return_value = {
-                    plugin_const.L3_ROUTER_NAT: plugin}
-                self.mixin.manager = manager
                 return router, subnet_v4, subnet_v6
 
     def test_undo_router_interface_change_on_csnat_error(self):
@@ -610,12 +597,12 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
     def test_remove_router_interface_csnat_ports_removal_with_ipv6(self):
         router, subnet_v4, subnet_v6 = self._setup_router_with_v4_and_v6()
         csnat_filters = {'device_owner':
-                         [l3_const.DEVICE_OWNER_ROUTER_SNAT]}
+                         [const.DEVICE_OWNER_ROUTER_SNAT]}
         csnat_ports = self.core_plugin.get_ports(
             self.ctx, filters=csnat_filters)
         self.assertEqual(2, len(csnat_ports))
         dvr_filters = {'device_owner':
-                       [l3_const.DEVICE_OWNER_DVR_INTERFACE]}
+                       [const.DEVICE_OWNER_DVR_INTERFACE]}
         dvr_ports = self.core_plugin.get_ports(
             self.ctx, filters=dvr_filters)
         self.assertEqual(2, len(dvr_ports))
@@ -642,7 +629,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
             self.ctx, router['id'],
             {'subnet_id': subnet_v4['subnet']['id']})
         csnat_filters = {'device_owner':
-                         [l3_const.DEVICE_OWNER_ROUTER_SNAT]}
+                         [const.DEVICE_OWNER_ROUTER_SNAT]}
         csnat_ports = self.core_plugin.get_ports(
             self.ctx, filters=csnat_filters)
         self.core_plugin.update_port(self.ctx, csnat_ports[0]['id'],
@@ -697,46 +684,45 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
         router_dict = {'name': 'test_router', 'admin_state_up': True,
                        'distributed': True}
         router = self._create_router(router_dict)
-        with mock.patch.object(manager.NeutronManager, 'get_plugin') as gp:
+        plugin = mock.Mock()
-            plugin = mock.Mock()
+        directory.add_plugin(const.CORE, plugin)
-            l3_notify = self.mixin.l3_rpc_notifier = mock.Mock()
+        l3_notify = self.mixin.l3_rpc_notifier = mock.Mock()
-            gp.return_value = plugin
+        port = {
-            port = {
+            'id': 'my_port_id',
-                'id': 'my_port_id',
+            'fixed_ips': [
-                'fixed_ips': [
+                {'subnet_id': '51edc9e0-24f9-47f2-8e1e-2a41cb691323',
-                    {'subnet_id': '51edc9e0-24f9-47f2-8e1e-2a41cb691323',
+                 'ip_address': '10.0.0.11'},
-                     'ip_address': '10.0.0.11'},
+                {'subnet_id': '2b7c8a07-6f8e-4937-8701-f1d5da1a807c',
-                    {'subnet_id': '2b7c8a07-6f8e-4937-8701-f1d5da1a807c',
+                 'ip_address': '10.0.0.21'},
-                     'ip_address': '10.0.0.21'},
+                {'subnet_id': '48534187-f077-4e81-93ff-81ec4cc0ad3b',
-                    {'subnet_id': '48534187-f077-4e81-93ff-81ec4cc0ad3b',
+                 'ip_address': 'fd45:1515:7e0:0:f816:3eff:fe1a:1111'}],
-                     'ip_address': 'fd45:1515:7e0:0:f816:3eff:fe1a:1111'}],
+            'mac_address': 'my_mac',
-                'mac_address': 'my_mac',
+            'device_owner': device_owner
-                'device_owner': device_owner
+        }
-            }
+        dvr_port = {
-            dvr_port = {
+            'id': 'dvr_port_id',
-                'id': 'dvr_port_id',
+            'fixed_ips': mock.ANY,
-                'fixed_ips': mock.ANY,
+            'device_owner': const.DEVICE_OWNER_DVR_INTERFACE,
-                'device_owner': l3_const.DEVICE_OWNER_DVR_INTERFACE,
+            'device_id': router['id']
-                'device_id': router['id']
+        }
-            }
+        plugin.get_ports.return_value = [dvr_port]
-            plugin.get_ports.return_value = [dvr_port]
+        if action == 'add':
-            if action == 'add':
+            self.mixin.update_arp_entry_for_dvr_service_port(
-                self.mixin.update_arp_entry_for_dvr_service_port(
+                self.ctx, port)
-                    self.ctx, port)
+            self.assertEqual(3, l3_notify.add_arp_entry.call_count)
-                self.assertEqual(3, l3_notify.add_arp_entry.call_count)
+        elif action == 'del':
-            elif action == 'del':
+            self.mixin.delete_arp_entry_for_dvr_service_port(
-                self.mixin.delete_arp_entry_for_dvr_service_port(
+                self.ctx, port)
-                    self.ctx, port)
+            self.assertEqual(3, l3_notify.del_arp_entry.call_count)
-                self.assertEqual(3, l3_notify.del_arp_entry.call_count)
 
     def test_update_arp_entry_for_dvr_service_port_added(self):
         action = 'add'
-        device_owner = l3_const.DEVICE_OWNER_LOADBALANCER
+        device_owner = const.DEVICE_OWNER_LOADBALANCER
         self._test_update_arp_entry_for_dvr_service_port(device_owner, action)
 
     def test_update_arp_entry_for_dvr_service_port_deleted(self):
         action = 'del'
-        device_owner = l3_const.DEVICE_OWNER_LOADBALANCER
+        device_owner = const.DEVICE_OWNER_LOADBALANCER
         self._test_update_arp_entry_for_dvr_service_port(device_owner, action)
 
     def test_add_router_interface_csnat_ports_failure(self):
@@ -766,7 +752,7 @@ class L3DvrTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
                 }
                 router_ports = self.core_plugin.get_ports(self.ctx, filters)
                 self.assertEqual(1, len(router_ports))
-                self.assertEqual(l3_const.DEVICE_OWNER_ROUTER_GW,
+                self.assertEqual(const.DEVICE_OWNER_ROUTER_GW,
                                  router_ports[0]['device_owner'])
 
     def test_add_router_interface_by_port_failure(self):

neutron/tests/unit/db/test_l3_hamode_db.py

@@ -15,6 +15,7 @@
 import mock
 from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_utils import uuidutils
@@ -36,7 +37,6 @@ from neutron.extensions import l3
 from neutron.extensions import l3_ext_ha_mode
 from neutron.extensions import portbindings
 from neutron.extensions import providernet
-from neutron import manager
 from neutron.scheduler import l3_agent_scheduler
 from neutron.tests.common import helpers
 from neutron.tests.unit import testlib_api
@@ -57,13 +57,14 @@ class L3HATestFramework(testlib_api.SqlTestCase):
 
         self.admin_ctx = context.get_admin_context()
         self.setup_coreplugin('ml2')
-        self.core_plugin = manager.NeutronManager.get_plugin()
+        self.core_plugin = directory.get_plugin()
         notif_p = mock.patch.object(l3_hamode_db.L3_HA_NAT_db_mixin,
                                     '_notify_ha_interfaces_updated')
         self.notif_m = notif_p.start()
         cfg.CONF.set_override('allow_overlapping_ips', True)
 
         self.plugin = FakeL3PluginWithAgents()
+        directory.add_plugin(constants.L3, self.plugin)
         self.plugin.router_scheduler = l3_agent_scheduler.ChanceScheduler()
         self.agent1 = helpers.register_l3_agent()
         self.agent2 = helpers.register_l3_agent(
@@ -412,14 +413,10 @@ class L3HATestCase(L3HATestFramework):
             self.admin_ctx, [router['id']])
         self.assertEqual(2, len(bound_agents))
 
-        with mock.patch.object(manager.NeutronManager,
+        self.plugin._unbind_ha_router(self.admin_ctx, router['id'])
-                               'get_service_plugins') as mock_manager:
-            self.plugin._unbind_ha_router(self.admin_ctx, router['id'])
-
         bound_agents = self.plugin.get_l3_agents_hosting_routers(
             self.admin_ctx, [router['id']])
         self.assertEqual(0, len(bound_agents))
-        self.assertEqual(2, mock_manager.call_count)
 
     def test_get_ha_sync_data_for_host_with_non_dvr_agent(self):
         with mock.patch.object(self.plugin,

neutron/tests/unit/dummy_plugin.py

@@ -14,13 +14,13 @@
 #    under the License.
 
 from neutron_lib import exceptions
+from neutron_lib.plugins import directory
 from oslo_utils import uuidutils
 
 from neutron.api import extensions
 from neutron.api.v2 import base
 from neutron.db import servicetype_db
 from neutron.extensions import servicetype
-from neutron import manager
 from neutron.plugins.common import constants
 from neutron.services import service_base
 
@@ -70,8 +70,7 @@ class Dummy(object):
     @classmethod
     def get_resources(cls):
         """Returns Extended Resource for dummy management."""
-        n_mgr = manager.NeutronManager.get_instance()
+        dummy_inst = directory.get_plugin('DUMMY')
-        dummy_inst = n_mgr.get_service_plugins()['DUMMY']
         controller = base.create_resource(
             COLLECTION_NAME, RESOURCE_NAME, dummy_inst,
             RESOURCE_ATTRIBUTE_MAP[COLLECTION_NAME])

neutron/tests/unit/extensions/base.py

@@ -25,6 +25,7 @@ import webtest
 
 from neutron.api import extensions
 from neutron.api.v2 import attributes
+from neutron import manager
 from neutron import quota
 from neutron.tests import tools
 from neutron.tests.unit.api import test_extensions
@@ -55,8 +56,8 @@ class ExtensionTestCase(testlib_api.WebTestCase):
         # Create the default configurations
         self.config_parse()
 
-        #just stubbing core plugin with plugin
+        # just stubbing core plugin with plugin
-        self.setup_coreplugin(plugin)
+        self.setup_coreplugin(plugin, load_plugins=False)
         cfg.CONF.set_override('core_plugin', plugin)
         if service_type:
             cfg.CONF.set_override('service_plugins', [plugin])
@@ -66,6 +67,8 @@ class ExtensionTestCase(testlib_api.WebTestCase):
         instance = self.plugin.return_value
         if service_type:
             instance.get_plugin_type.return_value = service_type
+        manager.init()
+
         if supported_extension_aliases is not None:
             instance.supported_extension_aliases = supported_extension_aliases
         if allow_pagination:

neutron/tests/unit/extensions/extensionattribute.py

@@ -15,9 +15,10 @@
 
 import abc
 
+from neutron_lib.plugins import directory
+
 from neutron.api import extensions
 from neutron.api.v2 import base
-from neutron import manager
 from neutron.quota import resource_registry
 
 
@@ -64,7 +65,7 @@ class Extensionattribute(extensions.ExtensionDescriptor):
     def get_resources(cls):
         """Returns Ext Resources."""
         exts = []
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         resource_name = 'ext_test_resource'
         collection_name = resource_name + "s"
         params = RESOURCE_ATTRIBUTE_MAP.get(collection_name, dict())

neutron/tests/unit/extensions/test_dns.py

@@ -16,13 +16,13 @@ import math
 
 import netaddr
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 
 from neutron.common import utils
 from neutron import context
 from neutron.db import db_base_plugin_v2
 from neutron.extensions import dns
-from neutron import manager
 from neutron.plugins.ml2 import config
 from neutron.tests.unit.db import test_db_base_plugin_v2
 from neutron.tests.unit.plugins.ml2 import test_plugin
@@ -125,7 +125,7 @@ class DnsExtensionTestCase(test_plugin.Ml2PluginV2TestCase):
             self.assertIn('mac_address', port['port'])
             ips = port['port']['fixed_ips']
             self.assertEqual(1, len(ips))
-            subnet_db = manager.NeutronManager.get_plugin().get_subnet(
+            subnet_db = directory.get_plugin().get_subnet(
                     context.get_admin_context(), ips[0]['subnet_id'])
             self.assertIn(netaddr.IPAddress(ips[0]['ip_address']),
                           netaddr.IPSet(netaddr.IPNetwork(subnet_db['cidr'])))

neutron/tests/unit/extensions/test_external_net.py

@@ -15,6 +15,7 @@
 
 import mock
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_utils import uuidutils
 import testtools
 from webob import exc
@@ -22,7 +23,6 @@ from webob import exc
 from neutron import context
 from neutron.db import models_v2
 from neutron.extensions import external_net as external_net
-from neutron import manager
 from neutron.tests.unit.api.v2 import test_base
 from neutron.tests.unit.db import test_db_base_plugin_v2
 
@@ -96,7 +96,7 @@ class ExtNetDBTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
                     query_params='router:external=False')
 
     def test_get_network_succeeds_without_filter(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.Context(None, None, is_admin=True)
         result = plugin.get_networks(ctx, filters=None)
         self.assertEqual([], result)
@@ -126,19 +126,19 @@ class ExtNetDBTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
             res = req.get_response(self.api)
             self.assertEqual(exc.HTTPOk.code, res.status_int)
             ctx = context.Context(None, None, is_admin=True)
-            plugin = manager.NeutronManager.get_plugin()
+            plugin = directory.get_plugin()
             result = plugin.get_networks(ctx)
             self.assertFalse(result[0]['shared'])
 
     def test_network_filter_hook_admin_context(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.Context(None, None, is_admin=True)
         model = models_v2.Network
         conditions = plugin._network_filter_hook(ctx, model, [])
         self.assertEqual([], conditions)
 
     def test_network_filter_hook_nonadmin_context(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         ctx = context.Context('edinson', 'cavani')
         model = models_v2.Network
         txt = ("networkrbacs.action = :action_1 AND "
@@ -184,13 +184,11 @@ class ExtNetDBTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase):
             self.assertTrue(ext_net['network'][external_net.EXTERNAL])
 
     def test_delete_network_check_disassociated_floatingips(self):
-        with mock.patch.object(manager.NeutronManager,
+        l3_mock = mock.Mock()
-                               'get_service_plugins') as srv_plugins:
+        directory.add_plugin('L3_ROUTER_NAT', l3_mock)
-            l3_mock = mock.Mock()
+        with self.network() as net:
-            srv_plugins.return_value = {'L3_ROUTER_NAT': l3_mock}
+            req = self.new_delete_request('networks', net['network']['id'])
-            with self.network() as net:
+            res = req.get_response(self.api)
-                req = self.new_delete_request('networks', net['network']['id'])
+            self.assertEqual(exc.HTTPNoContent.code, res.status_int)
-                res = req.get_response(self.api)
+            (l3_mock.delete_disassociated_floatingips
-                self.assertEqual(exc.HTTPNoContent.code, res.status_int)
+             .assert_called_once_with(mock.ANY, net['network']['id']))
-                (l3_mock.delete_disassociated_floatingips
-                 .assert_called_once_with(mock.ANY, net['network']['id']))

neutron/tests/unit/extensions/test_l3.py

@@ -21,6 +21,7 @@ import mock
 import netaddr
 from neutron_lib import constants as lib_constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_utils import importutils
 from oslo_utils import uuidutils
@@ -49,7 +50,6 @@ from neutron.db import models_v2
 from neutron.extensions import external_net
 from neutron.extensions import l3
 from neutron.extensions import portbindings
-from neutron import manager
 from neutron.plugins.common import constants as service_constants
 from neutron.tests import base
 from neutron.tests.common import helpers
@@ -93,9 +93,9 @@ class L3NatExtensionTestCase(test_extensions_base.ExtensionTestCase):
     def setUp(self):
         super(L3NatExtensionTestCase, self).setUp()
         self._setUpExtension(
-            'neutron.extensions.l3.RouterPluginBase', None,
+            'neutron.services.l3_router.l3_router_plugin.L3RouterPlugin',
-            l3.RESOURCE_ATTRIBUTE_MAP, l3.L3, '',
+            lib_constants.L3, l3.RESOURCE_ATTRIBUTE_MAP,
-            allow_pagination=True, allow_sorting=True,
+            l3.L3, '', allow_pagination=True, allow_sorting=True,
             supported_extension_aliases=['router'],
             use_quota=True)
 
@@ -257,8 +257,7 @@ class TestL3NatBasePlugin(db_base_plugin_v2.NeutronDbPluginV2,
             super(TestL3NatBasePlugin, self).delete_network(context, id)
 
     def delete_port(self, context, id, l3_port_check=True):
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT)
         if plugin:
             if l3_port_check:
                 plugin.prevent_l3_port_deletion(context, id)
@@ -1244,7 +1243,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
 
     def test_router_add_interface_delete_port_after_failure(self):
         with self.router() as r, self.subnet(enable_dhcp=False) as s:
-            plugin = manager.NeutronManager.get_plugin()
+            plugin = directory.get_plugin()
             # inject a failure in the update port that happens at the end
             # to ensure the port gets deleted
             with mock.patch.object(
@@ -2045,8 +2044,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
             self.assertIsNotNone(body['floatingip']['router_id'])
 
     def test_create_floatingip_non_admin_context_agent_notification(self):
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
         if not hasattr(plugin, 'l3_rpc_notifier'):
             self.skipTest("Plugin does not support l3_rpc_notifier")
 
@@ -2848,8 +2846,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
     def test_floatingip_via_router_interface_returns_201(self):
         # Override get_router_for_floatingip, as
         # networking-midonet's L3 service plugin would do.
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
         with mock.patch.object(plugin, "get_router_for_floatingip",
             self._get_router_for_floatingip_without_device_owner_check):
             self._test_floatingip_via_router_interface(exc.HTTPCreated.code)
@@ -2989,8 +2986,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
             self.assertEqual(exc.HTTPConflict.code, res.status_int)
 
     def test_router_specify_id_backend(self):
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-                    service_constants.L3_ROUTER_NAT]
         router_req = {'router': {'id': _uuid(), 'name': 'router',
                                  'tenant_id': 'foo',
                                  'admin_state_up': True}}
@@ -3045,8 +3041,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
 
     def test_create_router_gateway_fails_nested(self):
         # Force _update_router_gw_info failure
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
         if not isinstance(plugin, l3_db.L3_NAT_dbonly_mixin):
             self.skipTest("Plugin is not L3_NAT_dbonly_mixin")
         ctx = context.Context('', 'foo')
@@ -3077,8 +3072,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
 
     def test_create_router_gateway_fails_nested_delete_router_failed(self):
         # Force _update_router_gw_info failure
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
         if not isinstance(plugin, l3_db.L3_NAT_dbonly_mixin):
             self.skipTest("Plugin is not L3_NAT_dbonly_mixin")
         ctx = context.Context('', 'foo')
@@ -3115,8 +3109,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
 
     def test_router_add_interface_by_port_fails_nested(self):
         # Force _validate_router_port_info failure
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
         if not isinstance(plugin, l3_db.L3_NAT_dbonly_mixin):
             self.skipTest("Plugin is not L3_NAT_dbonly_mixin")
         orig_update_port = self.plugin.update_port
@@ -3169,8 +3162,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
         """Test to make sure notification to routers occurs when the gateway
             ip address of a subnet of the external network is changed.
         """
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
         if not hasattr(plugin, 'l3_rpc_notifier'):
             self.skipTest("Plugin does not support l3_rpc_notifier")
         # make sure the callback is registered.
@@ -3201,8 +3193,7 @@ class L3NatTestCaseBase(L3NatTestCaseMixin):
                                                       ['fake_device'], None)
 
     def test__notify_subnetpool_address_scope_update(self):
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
 
         tenant_id = _uuid()
         with mock.patch.object(
@@ -3349,8 +3340,7 @@ class L3AgentDbTestCaseBase(L3NatTestCaseMixin):
         l3_rpc_agent_api_str = (
             'neutron.api.rpc.agentnotifiers.l3_rpc_agent_api.L3AgentNotifyAPI')
         with mock.patch(l3_rpc_agent_api_str):
-            plugin = manager.NeutronManager.get_service_plugins()[
+            plugin = directory.get_plugin(lib_constants.L3)
-                service_constants.L3_ROUTER_NAT]
             notifyApi = plugin.l3_rpc_notifier
             kargs = [item for item in args]
             kargs.append(notifyApi)
@@ -3518,8 +3508,7 @@ class L3NatDBIntAgentSchedulingTestCase(L3BaseForIntTests,
         self.adminContext = context.get_admin_context()
 
     def _assert_router_on_agent(self, router_id, agent_host):
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT)
         agents = plugin.list_l3_agents_hosting_router(
             self.adminContext, router_id)['agents']
         self.assertEqual(1, len(agents))
@@ -3576,8 +3565,7 @@ class L3NatDBIntAgentSchedulingTestCase(L3BaseForIntTests,
             self._assert_router_on_agent(r['router']['id'], 'host2')
 
     def test_router_update_gateway_scheduling_not_supported(self):
-        plugin = manager.NeutronManager.get_service_plugins().get(
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT)
         mock.patch.object(plugin, 'router_supports_scheduling',
                           return_value=False).start()
         with self.router() as r:
@@ -3716,8 +3704,7 @@ class L3NatDBTestCaseMixin(object):
 
     def setUp(self):
         super(L3NatDBTestCaseMixin, self).setUp()
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
         if not isinstance(plugin, l3_db.L3_NAT_dbonly_mixin):
             self.skipTest("Plugin is not L3_NAT_dbonly_mixin")
 
@@ -3726,8 +3713,7 @@ class L3NatDBTestCaseMixin(object):
         the exception is propagated.
         """
 
-        plugin = manager.NeutronManager.get_service_plugins()[
+        plugin = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT]
         ctx = context.Context('', 'foo')
 
         class MyException(Exception):
@@ -3760,8 +3746,7 @@ class L3NatDBSepTestCase(L3BaseForSepTests, L3NatTestCaseBase,
     """Unit tests for a separate L3 routing service plugin."""
 
     def test_port_deletion_prevention_handles_missing_port(self):
-        pl = manager.NeutronManager.get_service_plugins().get(
+        pl = directory.get_plugin(lib_constants.L3)
-            service_constants.L3_ROUTER_NAT)
         self.assertIsNone(
             pl.prevent_l3_port_deletion(context.get_admin_context(), 'fakeid')
         )

neutron/tests/unit/extensions/test_l3_ext_gw_mode.py

@@ -17,6 +17,7 @@
 import mock
 import netaddr
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_serialization import jsonutils
@@ -34,7 +35,6 @@ from neutron.db.models import l3 as l3_models
 from neutron.db import models_v2
 from neutron.extensions import l3
 from neutron.extensions import l3_ext_gw_mode
-from neutron import manager
 from neutron.objects import network as net_obj
 from neutron.objects import subnet as subnet_obj
 from neutron.tests import base
@@ -400,7 +400,7 @@ class ExtGwModeIntTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase,
         with self.router() as r, self.subnet() as s:
             ext_net_id = s['subnet']['network_id']
             self._set_net_external(ext_net_id)
-            plugin = manager.NeutronManager.get_plugin()
+            plugin = directory.get_plugin()
             with mock.patch.object(plugin, '_get_port',
                                    side_effect=ValueError()):
                 self._set_router_external_gateway(r['router']['id'],

neutron/tests/unit/extensions/test_portsecurity.py

@@ -14,6 +14,7 @@
 # limitations under the License.
 
 from neutron_lib.api import validators
+from neutron_lib.plugins import directory
 from webob import exc
 
 from neutron import context
@@ -23,7 +24,6 @@ from neutron.db import portsecurity_db
 from neutron.db import securitygroups_db
 from neutron.extensions import portsecurity as psec
 from neutron.extensions import securitygroup as ext_sg
-from neutron import manager
 from neutron.tests.unit.db import test_db_base_plugin_v2
 from neutron.tests.unit.extensions import test_securitygroup
 
@@ -41,7 +41,7 @@ class PortSecurityTestCase(
         super(PortSecurityTestCase, self).setUp(plugin=plugin, ext_mgr=ext_mgr)
 
         # Check if a plugin supports security groups
-        plugin_obj = manager.NeutronManager.get_plugin()
+        plugin_obj = directory.get_plugin()
         self._skip_security_group = ('security-group' not in
                                      plugin_obj.supported_extension_aliases)
 

neutron/tests/unit/extensions/test_providernet.py

@@ -14,6 +14,8 @@
 #    under the License.
 
 import mock
+from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_utils import uuidutils
 from webob import exc as web_exc
@@ -23,7 +25,6 @@ from neutron.api import extensions
 from neutron.api.v2 import router
 from neutron import context
 from neutron.extensions import providernet as pnet
-from neutron import manager
 from neutron import quota
 from neutron.tests import tools
 from neutron.tests.unit.api import test_extensions
@@ -60,7 +61,7 @@ class ProvidernetExtensionTestCase(testlib_api.WebTestCase):
         self.useFixture(tools.AttributeMapMemento())
 
         # Update the plugin and extensions path
-        self.setup_coreplugin(plugin)
+        self.setup_coreplugin(plugin, load_plugins=False)
         cfg.CONF.set_override('allow_pagination', True)
         cfg.CONF.set_override('allow_sorting', True)
         self._plugin_patcher = mock.patch(plugin, autospec=True)
@@ -68,9 +69,9 @@ class ProvidernetExtensionTestCase(testlib_api.WebTestCase):
         # Ensure Quota checks never fail because of mock
         instance = self.plugin.return_value
         instance.get_networks_count.return_value = 1
-        # Instantiate mock plugin and enable the 'provider' extension
+        # Register mock plugin and enable the 'provider' extension
-        manager.NeutronManager.get_plugin().supported_extension_aliases = (
+        instance.supported_extension_aliases = ["provider"]
-            ["provider"])
+        directory.add_plugin(constants.CORE, instance)
         ext_mgr = ProviderExtensionManager()
         self.ext_mdw = test_extensions.setup_extensions_middleware(ext_mgr)
         self.addCleanup(self._plugin_patcher.stop)

neutron/tests/unit/extensions/test_securitygroup.py

@@ -18,6 +18,7 @@ import contextlib
 import mock
 from neutron_lib.api import validators
 from neutron_lib import constants as const
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 import oslo_db.exception as exc
 import six
@@ -31,7 +32,6 @@ from neutron.db import db_base_plugin_v2
 from neutron.db import securitygroups_db
 from neutron.extensions import securitygroup as ext_sg
 from neutron.extensions import standardattrdescription
-from neutron import manager
 from neutron.tests import base
 from neutron.tests.unit.db import test_db_base_plugin_v2
 
@@ -589,7 +589,7 @@ class TestSecurityGroups(SecurityGroupDBTestCase):
                     self.assertEqual(sg_rule[0][k], v)
 
     def test_get_security_group_on_port_from_wrong_tenant(self):
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         if not hasattr(plugin, '_get_security_groups_on_port'):
             self.skipTest("plugin doesn't use the mixin with this method")
         neutron_context = context.get_admin_context()

neutron/tests/unit/extensions/test_timestamp.py

@@ -16,6 +16,7 @@ import datetime
 import six
 
 import mock
+from neutron_lib.plugins import directory
 from oslo_utils import timeutils
 
 from neutron import context
@@ -55,15 +56,15 @@ class TimeStampChangedsinceTestCase(test_db_base_plugin_v2.
         ext_mgr = TimeStampExtensionManager()
         super(TimeStampChangedsinceTestCase, self).setUp(plugin=self.plugin,
                                                          ext_mgr=ext_mgr)
-        self.addCleanup(manager.NeutronManager.
+        self.addCleanup(
-                        get_service_plugins()['timestamp'].
+            directory.get_plugin('timestamp').unregister_db_events)
-                        unregister_db_events)
         self.addCleanup(manager.NeutronManager.clear_instance)
 
-    def setup_coreplugin(self, core_plugin=None):
+    def setup_coreplugin(self, core_plugin=None, load_plugins=True):
         super(TimeStampChangedsinceTestCase, self).setup_coreplugin(
-            self.plugin)
+            self.plugin, load_plugins=False)
         self.patched_default_svc_plugins.return_value = ['timestamp']
+        manager.init()
 
     def _get_resp_with_changed_since(self, resource_type, changed_since):
         query_params = 'changed_since=%s' % changed_since
@@ -227,7 +228,7 @@ class TimeStampChangedsinceTestCase(test_db_base_plugin_v2.
     def test_timestamp_fields_ignored_in_update(self):
         ctx = context.get_admin_context()
         with self.port() as port:
-            plugin = manager.NeutronManager.get_plugin()
+            plugin = directory.get_plugin()
             port = plugin.get_port(ctx, port['port']['id'])
             port['name'] = 'updated'
             port['created_at'] = '2011-04-06T14:34:23'

neutron/tests/unit/ipam/drivers/neutrondb_ipam/test_driver.py

@@ -17,6 +17,7 @@ import mock
 import netaddr
 from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 
 from neutron.common import constants as n_const
 from neutron import context
@@ -24,7 +25,6 @@ from neutron.ipam.drivers.neutrondb_ipam import db_models
 from neutron.ipam.drivers.neutrondb_ipam import driver
 from neutron.ipam import exceptions as ipam_exc
 from neutron.ipam import requests as ipam_req
-from neutron import manager
 from neutron.tests.unit.db import test_db_base_plugin_v2 as test_db_plugin
 from neutron.tests.unit import testlib_api
 
@@ -73,7 +73,7 @@ class TestNeutronDbIpamPool(testlib_api.SqlTestCase,
         self.setup_coreplugin(test_db_plugin.DB_PLUGIN_KLASS)
 
         # Prepare environment for tests
-        self.plugin = manager.NeutronManager.get_plugin()
+        self.plugin = directory.get_plugin()
         self.ctx = context.get_admin_context()
         self.network, self.net_id = self._create_network(self.plugin,
                                                          self.ctx)
@@ -264,7 +264,7 @@ class TestNeutronDbIpamSubnet(testlib_api.SqlTestCase,
         self.setup_coreplugin(test_db_plugin.DB_PLUGIN_KLASS)
 
         # Prepare environment for tests
-        self.plugin = manager.NeutronManager.get_plugin()
+        self.plugin = directory.get_plugin()
         self.ctx = context.get_admin_context()
         self.network, self.net_id = self._create_network(self.plugin,
                                                          self.ctx)

neutron/tests/unit/ipam/test_subnet_alloc.py

@@ -16,6 +16,7 @@
 import mock
 import netaddr
 from neutron_lib import constants
+from neutron_lib.plugins import directory
 from oslo_config import cfg
 from oslo_db import exception as db_exc
 from oslo_utils import uuidutils
@@ -24,7 +25,6 @@ from neutron.common import exceptions as n_exc
 from neutron import context
 from neutron.ipam import requests as ipam_req
 from neutron.ipam import subnet_alloc
-from neutron import manager
 from neutron.tests.unit.db import test_db_base_plugin_v2
 from neutron.tests.unit import testlib_api
 
@@ -35,7 +35,7 @@ class TestSubnetAllocation(testlib_api.SqlTestCase):
         super(TestSubnetAllocation, self).setUp()
         self._tenant_id = 'test-tenant'
         self.setup_coreplugin(test_db_base_plugin_v2.DB_PLUGIN_KLASS)
-        self.plugin = manager.NeutronManager.get_plugin()
+        self.plugin = directory.get_plugin()
         self.ctx = context.get_admin_context()
         cfg.CONF.set_override('allow_overlapping_ips', True)
 

neutron/tests/unit/notifiers/test_nova.py

@@ -17,6 +17,7 @@
 import mock
 from neutron_lib import constants as n_const
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 from novaclient import exceptions as nova_exceptions
 from oslo_config import cfg
 from oslo_utils import uuidutils
@@ -41,7 +42,7 @@ class TestNovaNotify(base.BaseTestCase):
                         'device_owner': DEVICE_OWNER_COMPUTE}
 
         self.nova_notifier = nova.Notifier()
-        self.nova_notifier._plugin_ref = FakePlugin()
+        directory.add_plugin(n_const.CORE, FakePlugin())
 
     def test_notify_port_status_all_values(self):
         states = [n_const.PORT_STATUS_ACTIVE, n_const.PORT_STATUS_DOWN,
@@ -180,7 +181,7 @@ class TestNovaNotify(base.BaseTestCase):
     def test_delete_floatingip_deleted_port_no_notify(self):
         port_id = 'bee50827-bcee-4cc8-91c1-a27b0ce54222'
         with mock.patch.object(
-            self.nova_notifier._plugin_ref, 'get_port',
+            directory.get_plugin(), 'get_port',
             side_effect=n_exc.PortNotFound(port_id=port_id)):
             returned_obj = {'floatingip':
                             {'port_id': port_id}}

neutron/tests/unit/objects/db/test_api.py

@@ -12,10 +12,10 @@
 
 import mock
 from neutron_lib import exceptions as n_exc
+from neutron_lib.plugins import directory
 
 from neutron import context
 from neutron.db import models_v2
-from neutron import manager
 from neutron.objects import base
 from neutron.objects.db import api
 from neutron.tests import base as test_base
@@ -40,7 +40,7 @@ class GetObjectsTestCase(test_base.BaseTestCase):
         limit = mock.sentinel.limit
         pager = base.Pager(marker=marker, limit=limit)
 
-        plugin = manager.NeutronManager.get_plugin()
+        plugin = directory.get_plugin()
         with mock.patch.object(plugin, '_get_collection') as get_collection:
             with mock.patch.object(api, 'get_object') as get_object:
                 api.get_objects(ctxt, model, _pager=pager)

neutron/tests/unit/objects/qos/test_rule_type.py

@@ -14,8 +14,8 @@
 # class on the common base class for all objects
 
 import mock
+from neutron_lib.plugins import directory
 
-from neutron import manager
 from neutron.objects.qos import rule_type
 from neutron.services.qos import qos_consts
 from neutron.tests import base as test_base
@@ -27,12 +27,12 @@ DB_PLUGIN_KLASS = 'neutron.db.db_base_plugin_v2.NeutronDbPluginV2'
 class QosRuleTypeObjectTestCase(test_base.BaseTestCase):
 
     def setUp(self):
+        super(QosRuleTypeObjectTestCase, self).setUp()
         self.config_parse()
         self.setup_coreplugin(DB_PLUGIN_KLASS)
-        super(QosRuleTypeObjectTestCase, self).setUp()
 
     def test_get_objects(self):
-        core_plugin = manager.NeutronManager.get_plugin()
+        core_plugin = directory.get_plugin()
         rule_types_mock = mock.PropertyMock(
             return_value=qos_consts.VALID_RULE_TYPES)
         with mock.patch.object(core_plugin, 'supported_qos_rule_types',

neutron/tests/unit/plugins/ml2/base.py

@@ -12,8 +12,9 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from neutron import manager
+from neutron_lib import constants
-from neutron.plugins.common import constants as plugin_constants
+from neutron_lib.plugins import directory
+
 from neutron.tests.unit.plugins.ml2 import test_plugin
 
 
@@ -30,9 +31,8 @@ class ML2TestFramework(test_plugin.Ml2PluginV2TestCase):
 
     def setUp(self):
         super(ML2TestFramework, self).setUp()
-        self.core_plugin = manager.NeutronManager.get_instance().get_plugin()
+        self.core_plugin = directory.get_plugin()
-        self.l3_plugin = manager.NeutronManager.get_service_plugins().get(
+        self.l3_plugin = directory.get_plugin(constants.L3)
-            plugin_constants.L3_ROUTER_NAT)
 
     def _create_router(self, distributed=False, ha=False):
         return self.l3_plugin.create_router(