Apply six for metaclass

__metaclass__ cannot be used in python3.
six be used in general for python 3 compatibility.

Change-Id: Ib0d71b9676dc01390679396443575c05975d3b58
Closes-Bug: #1236648

neutron/agent/firewall.py

@@ -18,7 +18,10 @@
 import abc
 import contextlib
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class FirewallDriver(object):
     """Firewall Driver base class.
 
@@ -52,8 +55,6 @@ class FirewallDriver(object):
       remote_group_id will also remaining membership update management
     """
 
-    __metaclass__ = abc.ABCMeta
-
     def prepare_port_filter(self, port):
         """Prepare filters for the port.
 

neutron/agent/l2population_rpc.py

@@ -20,12 +20,13 @@
 import abc
 
 from oslo.config import cfg
+import six
 
 from neutron.common import log
 
 
+@six.add_metaclass(abc.ABCMeta)
 class L2populationRpcCallBackMixin(object):
-    __metaclass__ = abc.ABCMeta
 
     @log.log
     def add_fdb_entries(self, context, fdb_entries, host=None):

neutron/agent/linux/dhcp.py

@@ -26,6 +26,7 @@ import uuid
 
 import netaddr
 from oslo.config import cfg
+import six
 
 from neutron.agent.linux import ip_lib
 from neutron.agent.linux import utils
@@ -101,8 +102,8 @@ class NetModel(DictModel):
         return self._ns_name
 
 
+@six.add_metaclass(abc.ABCMeta)
 class DhcpBase(object):
-    __metaclass__ = abc.ABCMeta
 
     def __init__(self, conf, network, root_helper='sudo',
                  version=None, plugin=None):

neutron/agent/linux/interface.py

@@ -19,6 +19,7 @@ import abc
 
 import netaddr
 from oslo.config import cfg
+import six
 
 from neutron.agent.common import config
 from neutron.agent.linux import ip_lib
@@ -59,8 +60,8 @@ OPTS = [
 ]
 
 
+@six.add_metaclass(abc.ABCMeta)
 class LinuxInterfaceDriver(object):
-    __metaclass__ = abc.ABCMeta
 
     # from linux IF_NAMESIZE
     DEV_NAME_LEN = 14

neutron/api/extensions.py

@@ -22,6 +22,7 @@ import os
 
 from oslo.config import cfg
 import routes
+import six
 import webob.dec
 import webob.exc
 
@@ -36,8 +37,8 @@ from neutron import wsgi
 LOG = logging.getLogger(__name__)
 
 
+@six.add_metaclass(ABCMeta)
 class PluginInterface(object):
-    __metaclass__ = ABCMeta
 
     @classmethod
     def __subclasshook__(cls, klass):

neutron/extensions/firewall.py

@@ -20,6 +20,7 @@
 import abc
 
 from oslo.config import cfg
+import six
 
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
@@ -376,8 +377,8 @@ class Firewall(extensions.ExtensionDescriptor):
             return {}
 
 
+@six.add_metaclass(abc.ABCMeta)
 class FirewallPluginBase(ServicePluginBase):
-    __metaclass__ = abc.ABCMeta
 
     def get_plugin_name(self):
         return constants.FIREWALL

neutron/extensions/loadbalancer.py

@@ -18,6 +18,7 @@
 import abc
 
 from oslo.config import cfg
+import six
 
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
@@ -376,8 +377,8 @@ class Loadbalancer(extensions.ExtensionDescriptor):
             return {}
 
 
+@six.add_metaclass(abc.ABCMeta)
 class LoadBalancerPluginBase(ServicePluginBase):
-    __metaclass__ = abc.ABCMeta
 
     def get_plugin_name(self):
         return constants.LOADBALANCER

neutron/extensions/metering.py

@@ -16,6 +16,8 @@
 
 import abc
 
+import six
+
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
 from neutron.api.v2 import base
@@ -147,8 +149,8 @@ class Metering(extensions.ExtensionDescriptor):
             return {}
 
 
+@six.add_metaclass(abc.ABCMeta)
 class MeteringPluginBase(service_base.ServicePluginBase):
-    __metaclass__ = abc.ABCMeta
 
     def get_plugin_name(self):
         return constants.METERING

neutron/extensions/securitygroup.py

@@ -19,6 +19,7 @@ from abc import ABCMeta
 from abc import abstractmethod
 
 from oslo.config import cfg
+import six
 
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
@@ -291,8 +292,8 @@ class Securitygroup(extensions.ExtensionDescriptor):
             return {}
 
 
+@six.add_metaclass(ABCMeta)
 class SecurityGroupPluginBase(object):
-    __metaclass__ = ABCMeta
 
     @abstractmethod
     def create_security_group(self, context, security_group):

neutron/extensions/vpnaas.py

@@ -20,6 +20,7 @@
 import abc
 
 from oslo.config import cfg
+import six
 
 from neutron.api import extensions
 from neutron.api.v2 import attributes as attr
@@ -405,8 +406,8 @@ class Vpnaas(extensions.ExtensionDescriptor):
             return {}
 
 
+@six.add_metaclass(abc.ABCMeta)
 class VPNPluginBase(ServicePluginBase):
-    __metaclass__ = abc.ABCMeta
 
     def get_plugin_name(self):
         return constants.VPN

neutron/neutron_plugin_base_v2.py

@@ -23,11 +23,12 @@ methods that needs to be implemented by a v2 Neutron Plug-in.
 
 from abc import ABCMeta, abstractmethod
 
+import six
 
+
+@six.add_metaclass(ABCMeta)
 class NeutronPluginBaseV2(object):
 
-    __metaclass__ = ABCMeta
-
     @abstractmethod
     def create_subnet(self, context, subnet):
         """Create a subnet.

neutron/plugins/cisco/l2device_plugin_base.py

@@ -19,7 +19,10 @@
 from abc import ABCMeta, abstractmethod
 import inspect
 
+import six
 
+
+@six.add_metaclass(ABCMeta)
 class L2DevicePluginBase(object):
     """Base class for a device-specific plugin.
 
@@ -28,8 +31,6 @@ class L2DevicePluginBase(object):
     the configuration on each device.
     """
 
-    __metaclass__ = ABCMeta
-
     @abstractmethod
     def get_all_networks(self, tenant_id, **kwargs):
         """Get newtorks.

neutron/plugins/embrane/l2base/support_base.py

@@ -19,7 +19,10 @@
 
 import abc
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class SupportBase(object):
     """abstract support class.
 
@@ -27,7 +30,6 @@ class SupportBase(object):
     the L2 base for Embrane plugin.
 
     """
-    __metaclass__ = abc.ABCMeta
 
     @abc.abstractmethod
     def __init__(self):

neutron/plugins/ml2/driver_api.py

@@ -15,6 +15,8 @@
 
 from abc import ABCMeta, abstractmethod, abstractproperty
 
+import six
+
 # The following keys are used in the segment dictionaries passed via
 # the driver API. These are defined separately from similar keys in
 # neutron.extensions.providernet so that drivers don't need to change
@@ -26,6 +28,7 @@ PHYSICAL_NETWORK = 'physical_network'
 SEGMENTATION_ID = 'segmentation_id'
 
 
+@six.add_metaclass(ABCMeta)
 class TypeDriver(object):
     """Define stable abstract interface for ML2 type drivers.
 
@@ -43,8 +46,6 @@ class TypeDriver(object):
     either be excluded or stored as None.
     """
 
-    __metaclass__ = ABCMeta
-
     @abstractmethod
     def get_type(self):
         """Get driver's network type.
@@ -128,6 +129,7 @@ class TypeDriver(object):
         pass
 
 
+@six.add_metaclass(ABCMeta)
 class NetworkContext(object):
     """Context passed to MechanismDrivers for changes to network resources.
 
@@ -137,8 +139,6 @@ class NetworkContext(object):
     MechanismDrivers can freely access the same information.
     """
 
-    __metaclass__ = ABCMeta
-
     @abstractproperty
     def current(self):
         """Return the current state of the network.
@@ -165,6 +165,7 @@ class NetworkContext(object):
         pass
 
 
+@six.add_metaclass(ABCMeta)
 class SubnetContext(object):
     """Context passed to MechanismDrivers for changes to subnet resources.
 
@@ -174,8 +175,6 @@ class SubnetContext(object):
     MechanismDrivers can freely access the same information.
     """
 
-    __metaclass__ = ABCMeta
-
     @abstractproperty
     def current(self):
         """Return the current state of the subnet.
@@ -197,6 +196,7 @@ class SubnetContext(object):
         pass
 
 
+@six.add_metaclass(ABCMeta)
 class PortContext(object):
     """Context passed to MechanismDrivers for changes to port resources.
 
@@ -206,8 +206,6 @@ class PortContext(object):
     freely access the same information.
     """
 
-    __metaclass__ = ABCMeta
-
     @abstractproperty
     def current(self):
         """Return the current state of the port.
@@ -262,6 +260,7 @@ class PortContext(object):
         pass
 
 
+@six.add_metaclass(ABCMeta)
 class MechanismDriver(object):
     """Define stable abstract interface for ML2 mechanism drivers.
 
@@ -283,8 +282,6 @@ class MechanismDriver(object):
     methods that are part of the database transaction.
     """
 
-    __metaclass__ = ABCMeta
-
     @abstractmethod
     def initialize(self):
         """Perform driver initialization.

neutron/plugins/ml2/drivers/mech_agent.py

@@ -15,12 +15,15 @@
 
 from abc import ABCMeta, abstractmethod
 
+import six
+
 from neutron.openstack.common import log
 from neutron.plugins.ml2 import driver_api as api
 
 LOG = log.getLogger(__name__)
 
 
+@six.add_metaclass(ABCMeta)
 class AgentMechanismDriverBase(api.MechanismDriver):
     """Base class for drivers that attach to networks using an L2 agent.
 
@@ -35,8 +38,6 @@ class AgentMechanismDriverBase(api.MechanismDriver):
     check_segment_for_agent().
     """
 
-    __metaclass__ = ABCMeta
-
     def __init__(self, agent_type, vif_type, cap_port_filter):
         """Initialize base class for specific L2 agent type.
 

neutron/plugins/ml2/drivers/type_tunnel.py

@@ -14,6 +14,8 @@
 #    under the License.
 from abc import ABCMeta, abstractmethod
 
+import six
+
 from neutron.common import exceptions as exc
 from neutron.common import topics
 from neutron.openstack.common import log
@@ -24,6 +26,7 @@ LOG = log.getLogger(__name__)
 TUNNEL = 'tunnel'
 
 
+@six.add_metaclass(ABCMeta)
 class TunnelTypeDriver(api.TypeDriver):
     """Define stable abstract interface for ML2 type drivers.
 
@@ -31,8 +34,6 @@ class TunnelTypeDriver(api.TypeDriver):
     methods to manage these endpoints.
     """
 
-    __metaclass__ = ABCMeta
-
     @abstractmethod
     def add_endpoint(self, ip):
         """Register the endpoint in the type_driver database.

neutron/plugins/nec/ofc_driver_base.py

@@ -18,7 +18,10 @@
 
 from abc import ABCMeta, abstractmethod
 
+import six
 
+
+@six.add_metaclass(ABCMeta)
 class OFCDriverBase(object):
     """OpenFlow Controller (OFC) Driver Specification.
 
@@ -26,8 +29,6 @@ class OFCDriverBase(object):
     It would be better that other methods like update_* are implemented.
     """
 
-    __metaclass__ = ABCMeta
-
     @abstractmethod
     def create_tenant(self, description, tenant_id=None):
         """Create a new tenant at OpenFlow Controller.

neutron/plugins/nec/router_drivers.py

@@ -19,6 +19,8 @@
 import abc
 import httplib
 
+import six
+
 from neutron.common import log as call_log
 from neutron.common import utils
 from neutron.openstack.common import excutils
@@ -31,10 +33,9 @@ LOG = logging.getLogger(__name__)
 PROVIDER_OPENFLOW = nconst.ROUTER_PROVIDER_OPENFLOW
 
 
+@six.add_metaclass(abc.ABCMeta)
 class RouterDriverBase(object):
 
-    __metaclass__ = abc.ABCMeta
-
     def __init__(self, plugin, ofc_manager):
         self.plugin = plugin
         self.ofc = ofc_manager

neutron/plugins/nicira/api_client/client.py

@@ -24,6 +24,7 @@ import httplib
 import logging
 import time
 
+import six
 
 from neutron.plugins.nicira.api_client.common import (
     _conn_str)
@@ -37,6 +38,7 @@ DEFAULT_CONCURRENT_CONNECTIONS = 3
 DEFAULT_CONNECT_TIMEOUT = 5
 
 
+@six.add_metaclass(ABCMeta)
 class NvpApiClient(object):
     '''An abstract baseclass for all NvpApiClient implementations.
 
@@ -44,8 +46,6 @@ class NvpApiClient(object):
     coroutine-based classes.
     '''
 
-    __metaclass__ = ABCMeta
-
     CONN_IDLE_TIMEOUT = 60 * 15
 
     def _create_connection(self, host, port, is_ssl):

neutron/plugins/nicira/api_client/request.py

@@ -26,6 +26,8 @@ import logging
 import time
 import urlparse
 
+import six
+
 from neutron.openstack.common import excutils
 from neutron.plugins.nicira.api_client.common import (
     _conn_str)
@@ -45,6 +47,7 @@ DOWNLOAD_TIMEOUT = 180  # The UI code has a coorespoind 190 sec timeout
                         # for downloads, see: django/nvp_console/views.py
 
 
+@six.add_metaclass(ABCMeta)
 class NvpApiRequest(object):
     '''An abstract baseclass for all ApiRequest implementations.
 
@@ -52,8 +55,6 @@ class NvpApiRequest(object):
     gevent-based ApiRequest classes.
     '''
 
-    __metaclass__ = ABCMeta
-
     # List of allowed status codes.
     ALLOWED_STATUS_CODES = [
         httplib.OK,

neutron/services/firewall/drivers/fwaas_base.py

@@ -19,7 +19,10 @@
 
 import abc
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class FwaasDriverBase(object):
     """Firewall as a Service Driver base class.
 
@@ -60,8 +63,6 @@ class FwaasDriverBase(object):
     application of rules.
     """
 
-    __metaclass__ = abc.ABCMeta
-
     @abc.abstractmethod
     def create_firewall(self, apply_list, firewall):
         """Create the Firewall with default (drop all) policy.

neutron/services/loadbalancer/drivers/abstract_driver.py

@@ -18,7 +18,10 @@
 
 import abc
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class LoadBalancerAbstractDriver(object):
     """Abstract lbaas driver that expose ~same API as lbaas plugin.
 
@@ -27,7 +30,6 @@ class LoadBalancerAbstractDriver(object):
     Get operations are not part of the API - it will be handled
     by the lbaas plugin.
     """
-    __metaclass__ = abc.ABCMeta
 
     @abc.abstractmethod
     def create_vip(self, context, vip):

neutron/services/metering/drivers/abstract_driver.py

@@ -16,10 +16,12 @@
 
 import abc
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class MeteringAbstractDriver(object):
     """Abstract Metering driver."""
-    __metaclass__ = abc.ABCMeta
 
     def __init__(self, plugin, conf):
         pass

neutron/services/service_base.py

@@ -17,6 +17,8 @@
 
 import abc
 
+import six
+
 from neutron.api import extensions
 from neutron.db import servicetype_db as sdb
 from neutron.openstack.common import importutils
@@ -26,9 +28,9 @@ from neutron.services import provider_configuration as pconf
 LOG = logging.getLogger(__name__)
 
 
+@six.add_metaclass(abc.ABCMeta)
 class ServicePluginBase(extensions.PluginInterface):
     """Define base interface for any Advanced Service plugin."""
-    __metaclass__ = abc.ABCMeta
     supported_extension_aliases = []
 
     @abc.abstractmethod

neutron/services/vpn/device_drivers/__init__.py

@@ -16,9 +16,11 @@
 #    under the License.
 import abc
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class DeviceDriver(object):
-    __metaclass__ = abc.ABCMeta
 
     def __init__(self, agent, host):
         pass

neutron/services/vpn/device_drivers/ipsec.py

@@ -23,6 +23,7 @@ import shutil
 import jinja2
 import netaddr
 from oslo.config import cfg
+import six
 
 from neutron.agent.linux import ip_lib
 from neutron.agent.linux import utils
@@ -85,13 +86,13 @@ def _get_template(template_file):
     return JINJA_ENV.get_template(template_file)
 
 
+@six.add_metaclass(abc.ABCMeta)
 class BaseSwanProcess():
     """Swan Family Process Manager
 
     This class manages start/restart/stop ipsec process.
     This class create/delete config template
     """
-    __metaclass__ = abc.ABCMeta
 
     binary = "ipsec"
     CONFIG_DIRS = [
@@ -465,6 +466,7 @@ class IPsecVpnDriverApi(proxy.RpcProxy):
                          topic=self.topic)
 
 
+@six.add_metaclass(abc.ABCMeta)
 class IPsecDriver(device_drivers.DeviceDriver):
     """VPN Device Driver for IPSec.
 
@@ -478,7 +480,6 @@ class IPsecDriver(device_drivers.DeviceDriver):
     #   1.0 Initial version
 
     RPC_API_VERSION = '1.0'
-    __metaclass__ = abc.ABCMeta
 
     def __init__(self, agent, host):
         self.agent = agent

neutron/services/vpn/service_drivers/__init__.py

@@ -17,9 +17,11 @@
 
 import abc
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class VpnDriver(object):
-    __metaclass__ = abc.ABCMeta
 
     @property
     def service_type(self):