Remove six[7]

Since our code will only support py3. So remove six is necessary.

Change-Id: I3738118b1898421ee41e9e2902c255ead73f3915

tox.ini

@@ -26,7 +26,7 @@ passenv = http_proxy HTTP_PROXY https_proxy HTTPS_PROXY no_proxy NO_PROXY
 commands =
     doc8 doc/source/ CONTRIBUTING.rst HACKING.rst README.rst
     flake8
-    bandit -r watcher -x watcher/tests/* -n5 -ll -s B320
+    bandit -r watcher -x watcher/tests/* -n5 -ll -s B320,B322
 
 [testenv:venv]
 setenv = PYTHONHASHSEED=0

watcher/api/hooks.py

@@ -15,9 +15,9 @@
 # under the License.
 
 
+from http import client as http_client
 from oslo_config import cfg
 from pecan import hooks
-from six.moves import http_client
 
 from watcher.common import context
 

watcher/api/middleware/parsable_error.py

@@ -24,7 +24,6 @@ from xml import etree as et
 
 from oslo_log import log
 from oslo_serialization import jsonutils
-import six
 import webob
 
 from watcher._i18n import _
@@ -84,12 +83,10 @@ class ParsableErrorMiddleware(object):
                             '</error_message>' % state['status_code']]
                 state['headers'].append(('Content-Type', 'application/xml'))
             else:
-                if six.PY3:
-                    app_iter = [i.decode('utf-8') for i in app_iter]
+                app_iter = [i.decode('utf-8') for i in app_iter]
                 body = [jsonutils.dumps(
                     {'error_message': '\n'.join(app_iter)})]
-                if six.PY3:
-                    body = [item.encode('utf-8') for item in body]
+                body = [item.encode('utf-8') for item in body]
                 state['headers'].append(('Content-Type', 'application/json'))
             state['headers'].append(('Content-Length', str(len(body[0]))))
         else:

watcher/api/scheduling.py

@@ -20,7 +20,6 @@ import itertools
 from oslo_config import cfg
 from oslo_log import log
 from oslo_utils import timeutils
-import six
 
 from watcher.common import context as watcher_context
 from watcher.common import scheduling
@@ -83,7 +82,7 @@ class APISchedulingService(scheduling.BackgroundSchedulerService):
         service = objects.Service.get(context, service_id)
         last_heartbeat = (service.last_seen_up or service.updated_at or
                           service.created_at)
-        if isinstance(last_heartbeat, six.string_types):
+        if isinstance(last_heartbeat, str):
             # NOTE(russellb) If this service came in over rpc via
             # conductor, then the timestamp will be a string and needs to be
             # converted back to a datetime.

watcher/applier/action_plan/base.py

@@ -18,11 +18,9 @@
 #
 
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseActionPlanHandler(object):
+class BaseActionPlanHandler(object, metaclass=abc.ABCMeta):
     @abc.abstractmethod
     def execute(self):
         raise NotImplementedError()

watcher/applier/actions/base.py

@@ -19,14 +19,12 @@
 import abc
 
 import jsonschema
-import six
 
 from watcher.common import clients
 from watcher.common.loader import loadable
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseAction(loadable.Loadable):
+class BaseAction(loadable.Loadable, metaclass=abc.ABCMeta):
     # NOTE(jed): by convention we decided
     # that the attribute "resource_id" is the unique id of
     # the resource to which the Action applies to allow us to use it in the

watcher/applier/base.py

@@ -26,11 +26,9 @@ See: :doc:`../architecture` for more details on this component.
 """
 
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseApplier(object):
+class BaseApplier(object, metaclass=abc.ABCMeta):
     @abc.abstractmethod
     def execute(self, action_plan_uuid):
         raise NotImplementedError()

watcher/applier/workflow_engine/base.py

@@ -17,7 +17,6 @@
 #
 
 import abc
-import six
 import time
 
 import eventlet
@@ -40,8 +39,7 @@ CANCEL_STATE = [objects.action_plan.State.CANCELLING,
                 objects.action_plan.State.CANCELLED]
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseWorkFlowEngine(loadable.Loadable):
+class BaseWorkFlowEngine(loadable.Loadable, metaclass=abc.ABCMeta):
 
     def __init__(self, config, context=None, applier_manager=None):
         """Constructor

watcher/common/context.py

@@ -13,7 +13,6 @@
 from oslo_context import context
 from oslo_log import log
 from oslo_utils import timeutils
-import six
 
 LOG = log.getLogger(__name__)
 
@@ -69,7 +68,7 @@ class RequestContext(context.RequestContext):
         self.project_id = project_id
         if not timestamp:
             timestamp = timeutils.utcnow()
-        if isinstance(timestamp, six.string_types):
+        if isinstance(timestamp, str):
             timestamp = timeutils.parse_isotime(timestamp)
         self.timestamp = timestamp
         self.user_name = user_name

watcher/common/loader/base.py

@@ -17,11 +17,9 @@
 from __future__ import unicode_literals
 
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseLoader(object):
+class BaseLoader(object, metaclass=abc.ABCMeta):
 
     @abc.abstractmethod
     def list_available(self):

watcher/common/loader/loadable.py

@@ -16,13 +16,10 @@
 
 import abc
 
-import six
-
 from watcher.common import service
 
 
-@six.add_metaclass(abc.ABCMeta)
-class Loadable(object):
+class Loadable(object, metaclass=abc.ABCMeta):
     """Generic interface for dynamically loading a driver/entry point.
 
     This defines the contract in order to let the loader manager inject
@@ -48,8 +45,7 @@ LoadableSingletonMeta = type(
     "LoadableSingletonMeta", (abc.ABCMeta, service.Singleton), {})
 
 
-@six.add_metaclass(LoadableSingletonMeta)
-class LoadableSingleton(object):
+class LoadableSingleton(object, metaclass=LoadableSingletonMeta):
     """Generic interface for dynamically loading a driver as a singleton.
 
     This defines the contract in order to let the loader manager inject

watcher/common/service_manager.py

@@ -15,11 +15,9 @@
 # under the License.
 
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ServiceManager(object):
+class ServiceManager(object, metaclass=abc.ABCMeta):
 
     @abc.abstractproperty
     def service_name(self):

watcher/common/utils.py

@@ -28,7 +28,6 @@ from oslo_config import cfg
 from oslo_log import log
 from oslo_utils import strutils
 from oslo_utils import uuidutils
-import six
 
 from watcher.common import exception
 
@@ -82,7 +81,7 @@ def safe_rstrip(value, chars=None):
     :return: Stripped value.
 
     """
-    if not isinstance(value, six.string_types):
+    if not isinstance(value, str):
         LOG.warning(
             "Failed to remove trailing character. Returning original object."
             "Supplied object is not a string: %s,", value)
@@ -104,7 +103,7 @@ def is_hostname_safe(hostname):
 
     """
     m = r'^[a-z0-9]([a-z0-9\-]{0,61}[a-z0-9])?$'
-    return (isinstance(hostname, six.string_types) and
+    return (isinstance(hostname, str) and
             (re.match(m, hostname) is not None))
 
 

watcher/db/api.py

@@ -18,7 +18,6 @@ Base classes for storage engines
 import abc
 from oslo_config import cfg
 from oslo_db import api as db_api
-import six
 
 _BACKEND_MAPPING = {'sqlalchemy': 'watcher.db.sqlalchemy.api'}
 IMPL = db_api.DBAPI.from_config(cfg.CONF, backend_mapping=_BACKEND_MAPPING,
@@ -30,8 +29,7 @@ def get_instance():
     return IMPL
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseConnection(object):
+class BaseConnection(object, metaclass=abc.ABCMeta):
     """Base class for storage system connections."""
 
     @abc.abstractmethod

watcher/db/purge.py

@@ -25,7 +25,6 @@ import sys
 from oslo_log import log
 from oslo_utils import strutils
 import prettytable as ptable
-from six.moves import input
 
 from watcher._i18n import _
 from watcher._i18n import lazy_translation_enabled

watcher/decision_engine/audit/base.py

@@ -18,7 +18,6 @@
 # limitations under the License.
 #
 import abc
-import six
 
 from oslo_config import cfg
 from oslo_log import log
@@ -36,9 +35,11 @@ CONF = cfg.CONF
 LOG = log.getLogger(__name__)
 
 
-@six.add_metaclass(abc.ABCMeta)
-@six.add_metaclass(service.Singleton)
-class BaseAuditHandler(object):
+class BaseMetaClass(service.Singleton, abc.ABCMeta):
+    pass
+
+
+class BaseAuditHandler(object, metaclass=BaseMetaClass):
 
     @abc.abstractmethod
     def execute(self, audit, request_context):
@@ -57,8 +58,7 @@ class BaseAuditHandler(object):
         raise NotImplementedError()
 
 
-@six.add_metaclass(abc.ABCMeta)
-class AuditHandler(BaseAuditHandler):
+class AuditHandler(BaseAuditHandler, metaclass=abc.ABCMeta):
 
     def __init__(self):
         super(AuditHandler, self).__init__()

watcher/decision_engine/datasources/grafana.py

@@ -16,9 +16,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from urllib import parse as urlparse
+
 from oslo_config import cfg
 from oslo_log import log
-import six.moves.urllib.parse as urlparse
 
 from watcher.common import clients
 from watcher.common import exception

watcher/decision_engine/goal/base.py

@@ -15,13 +15,11 @@
 # limitations under the License.
 
 import abc
-import six
 
 from watcher.common.loader import loadable
 
 
-@six.add_metaclass(abc.ABCMeta)
-class Goal(loadable.Loadable):
+class Goal(loadable.Loadable, metaclass=abc.ABCMeta):
 
     def __init__(self, config):
         super(Goal, self).__init__(config)

watcher/decision_engine/goal/efficacy/base.py

@@ -27,11 +27,8 @@ import abc
 import jsonschema
 from oslo_serialization import jsonutils
 
-import six
 
-
-@six.add_metaclass(abc.ABCMeta)
-class EfficacySpecification(object):
+class EfficacySpecification(object, metaclass=abc.ABCMeta):
 
     def __init__(self):
         self._indicators_specs = self.get_indicators_specifications()

watcher/decision_engine/goal/efficacy/indicators.py

@@ -18,7 +18,6 @@ import abc
 import jsonschema
 from jsonschema import SchemaError
 from jsonschema import ValidationError
-import six
 
 from oslo_log import log
 from oslo_serialization import jsonutils
@@ -29,8 +28,7 @@ from watcher.common import exception
 LOG = log.getLogger(__name__)
 
 
-@six.add_metaclass(abc.ABCMeta)
-class IndicatorSpecification(object):
+class IndicatorSpecification(object, metaclass=abc.ABCMeta):
 
     def __init__(self, name=None, description=None, unit=None, required=True):
         self.name = name

watcher/decision_engine/model/base.py

@@ -25,11 +25,9 @@ See: :doc:`../architecture` for more details on this component.
 """
 
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class Model(object):
+class Model(object, metaclass=abc.ABCMeta):
 
     @abc.abstractmethod
     def to_string(self):

watcher/decision_engine/model/collector/base.py

@@ -110,7 +110,6 @@ import time
 
 from oslo_config import cfg
 from oslo_log import log
-import six
 
 from watcher.common import clients
 from watcher.common.loader import loadable
@@ -120,8 +119,8 @@ LOG = log.getLogger(__name__)
 CONF = cfg.CONF
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseClusterDataModelCollector(loadable.LoadableSingleton):
+class BaseClusterDataModelCollector(loadable.LoadableSingleton,
+                                    metaclass=abc.ABCMeta):
 
     STALE_MODEL = model_root.ModelRoot(stale=True)
 

watcher/decision_engine/model/collector/cinder.py

@@ -13,8 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import six
-
 from oslo_log import log
 
 from watcher.common import cinder_helper
@@ -286,7 +284,7 @@ class CinderModelBuilder(base.BaseModelBuilder):
         :param instance: Cinder Volume object.
         :return: A volume node for the graph.
         """
-        attachments = [{k: v for k, v in six.iteritems(d) if k in (
+        attachments = [{k: v for k, v in iter(d.items()) if k in (
             'server_id', 'attachment_id')} for d in volume.attachments]
 
         volume_attributes = {

watcher/decision_engine/model/element/baremetal_resource.py

@@ -16,14 +16,12 @@
 
 import abc
 
-import six
 
 from watcher.decision_engine.model.element import base
 from watcher.objects import fields as wfields
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaremetalResource(base.Element):
+class BaremetalResource(base.Element, metaclass=abc.ABCMeta):
 
     VERSION = '1.0'
 

watcher/decision_engine/model/element/base.py

@@ -21,7 +21,6 @@ import collections
 
 from lxml import etree
 from oslo_log import log
-import six
 
 from watcher.objects import base
 from watcher.objects import fields as wfields
@@ -29,9 +28,8 @@ from watcher.objects import fields as wfields
 LOG = log.getLogger(__name__)
 
 
-@six.add_metaclass(abc.ABCMeta)
 class Element(base.WatcherObject, base.WatcherObjectDictCompat,
-              base.WatcherComparableObject):
+              base.WatcherComparableObject, metaclass=abc.ABCMeta):
 
     # Initial version
     VERSION = '1.0'

watcher/decision_engine/model/element/compute_resource.py

@@ -16,14 +16,12 @@
 
 import abc
 
-import six
 
 from watcher.decision_engine.model.element import base
 from watcher.objects import fields as wfields
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ComputeResource(base.Element):
+class ComputeResource(base.Element, metaclass=abc.ABCMeta):
 
     VERSION = '1.0'
 

watcher/decision_engine/model/element/storage_resource.py

@@ -16,14 +16,12 @@
 
 import abc
 
-import six
 
 from watcher.decision_engine.model.element import base
 from watcher.objects import fields as wfields
 
 
-@six.add_metaclass(abc.ABCMeta)
-class StorageResource(base.Element):
+class StorageResource(base.Element, metaclass=abc.ABCMeta):
 
     VERSION = '1.0'
 

watcher/decision_engine/model/model_root.py

@@ -21,7 +21,6 @@ from lxml import etree
 import networkx as nx
 from oslo_concurrency import lockutils
 from oslo_log import log
-import six
 
 from watcher._i18n import _
 from watcher.common import exception
@@ -93,9 +92,9 @@ class ModelRoot(nx.DiGraph, base.Model):
         :param node: :py:class:`~.node.ComputeNode` object or node UUID
         :type node: str or :py:class:`~.instance.Instance`
         """
-        if isinstance(instance, six.string_types):
+        if isinstance(instance, str):
             instance = self.get_instance_by_uuid(instance)
-        if isinstance(node, six.string_types):
+        if isinstance(node, str):
             node = self.get_node_by_uuid(node)
         self.assert_node(node)
         self.assert_instance(instance)
@@ -104,9 +103,9 @@ class ModelRoot(nx.DiGraph, base.Model):
 
     @lockutils.synchronized("model_root")
     def unmap_instance(self, instance, node):
-        if isinstance(instance, six.string_types):
+        if isinstance(instance, str):
             instance = self.get_instance_by_uuid(instance)
-        if isinstance(node, six.string_types):
+        if isinstance(node, str):
             node = self.get_node_by_uuid(node)
 
         self.remove_edge(instance.uuid, node.uuid)
@@ -367,9 +366,9 @@ class StorageModelRoot(nx.DiGraph, base.Model):
         :param pool: :py:class:`~.node.Pool` object or pool name
         :param node: :py:class:`~.node.StorageNode` object or node host
         """
-        if isinstance(pool, six.string_types):
+        if isinstance(pool, str):
             pool = self.get_pool_by_pool_name(pool)
-        if isinstance(node, six.string_types):
+        if isinstance(node, str):
             node = self.get_node_by_name(node)
         self.assert_node(node)
         self.assert_pool(pool)
@@ -383,9 +382,9 @@ class StorageModelRoot(nx.DiGraph, base.Model):
         :param pool: :py:class:`~.node.Pool` object or pool name
         :param node: :py:class:`~.node.StorageNode` object or node name
         """
-        if isinstance(pool, six.string_types):
+        if isinstance(pool, str):
             pool = self.get_pool_by_pool_name(pool)
-        if isinstance(node, six.string_types):
+        if isinstance(node, str):
             node = self.get_node_by_name(node)
 
         self.remove_edge(pool.name, node.host)
@@ -411,9 +410,9 @@ class StorageModelRoot(nx.DiGraph, base.Model):
         :param volume: :py:class:`~.volume.Volume` object or volume UUID
         :param pool: :py:class:`~.node.Pool` object or pool name
         """
-        if isinstance(volume, six.string_types):
+        if isinstance(volume, str):
             volume = self.get_volume_by_uuid(volume)
-        if isinstance(pool, six.string_types):
+        if isinstance(pool, str):
             pool = self.get_pool_by_pool_name(pool)
         self.assert_pool(pool)
         self.assert_volume(volume)
@@ -427,9 +426,9 @@ class StorageModelRoot(nx.DiGraph, base.Model):
         :param volume: :py:class:`~.volume.Volume` object or volume UUID
         :param pool: :py:class:`~.node.Pool` object or pool name
         """
-        if isinstance(volume, six.string_types):
+        if isinstance(volume, str):
             volume = self.get_volume_by_uuid(volume)
-        if isinstance(pool, six.string_types):
+        if isinstance(pool, str):
             pool = self.get_pool_by_pool_name(pool)
 
         self.remove_edge(volume.uuid, pool.name)

watcher/decision_engine/model/notification/base.py

@@ -17,11 +17,9 @@
 # limitations under the License.
 
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class NotificationEndpoint(object):
+class NotificationEndpoint(object, metaclass=abc.ABCMeta):
 
     def __init__(self, collector):
         super(NotificationEndpoint, self).__init__()

watcher/decision_engine/model/notification/cinder.py

@@ -14,8 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import six
-
 from oslo_log import log
 from watcher.common import cinder_helper
 from watcher.common import exception
@@ -161,7 +159,7 @@ class CinderNotification(base.NotificationEndpoint):
                 return 'attachment_id'
 
         attachments = [
-            {_keyReplace(k): v for k, v in six.iteritems(d)
+            {_keyReplace(k): v for k, v in iter(d.items())
                 if k in ('instance_uuid', 'id')}
             for d in data['volume_attachment']
         ]

watcher/decision_engine/model/notification/filtering.py

@@ -19,7 +19,6 @@
 import re
 
 import oslo_messaging as om
-import six
 
 
 class NotificationFilter(om.NotificationFilter):
@@ -81,7 +80,7 @@ class NotificationFilter(om.NotificationFilter):
         elif regex is not None and data is None:
             return True
         elif (regex is not None and
-              isinstance(data, six.string_types) and
+              isinstance(data, str) and
               not regex.match(data)):
             return True
 

watcher/decision_engine/planner/base.py

@@ -45,13 +45,11 @@ See :doc:`../architecture` for more details on this component.
 """
 
 import abc
-import six
 
 from watcher.common.loader import loadable
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BasePlanner(loadable.Loadable):
+class BasePlanner(loadable.Loadable, metaclass=abc.ABCMeta):
 
     @classmethod
     def get_config_opts(cls):

watcher/decision_engine/scope/base.py

@@ -16,13 +16,11 @@
 #
 
 import abc
-import six
 
 from watcher.common import context
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseScope(object):
+class BaseScope(object, metaclass=abc.ABCMeta):
     """A base class for Scope mechanism
 
     Child of this class is called when audit launches strategy. This strategy

watcher/decision_engine/scoring/base.py

@@ -17,13 +17,11 @@
 # limitations under the License.
 
 import abc
-import six
 
 from watcher.common.loader import loadable
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ScoringEngine(loadable.Loadable):
+class ScoringEngine(loadable.Loadable, metaclass=abc.ABCMeta):
     """A base class for all the Scoring Engines.
 
     A Scoring Engine is an instance of a data model, to which the learning
@@ -97,8 +95,7 @@ class ScoringEngine(loadable.Loadable):
         return []
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ScoringEngineContainer(loadable.Loadable):
+class ScoringEngineContainer(loadable.Loadable, metaclass=abc.ABCMeta):
     """A base class for all the Scoring Engines Containers.
 
     A Scoring Engine Container is an abstraction which allows to plugin

watcher/decision_engine/solution/base.py

@@ -56,13 +56,11 @@ Two approaches to dealing with this can be envisaged:
 """
 
 import abc
-import six
 
 from watcher.decision_engine.solution import efficacy
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseSolution(object):
+class BaseSolution(object, metaclass=abc.ABCMeta):
     def __init__(self, goal, strategy):
         """Base Solution constructor
 

watcher/decision_engine/solution/solution_comparator.py

@@ -17,11 +17,9 @@
 # limitations under the License.
 #
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseSolutionComparator(object):
+class BaseSolutionComparator(object, metaclass=abc.ABCMeta):
     @abc.abstractmethod
     def compare(self, sol1, sol2):
         raise NotImplementedError()

watcher/decision_engine/solution/solution_evaluator.py

@@ -17,11 +17,9 @@
 # limitations under the License.
 #
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseSolutionEvaluator(object):
+class BaseSolutionEvaluator(object, metaclass=abc.ABCMeta):
     @abc.abstractmethod
     def evaluate(self, solution):
         raise NotImplementedError()

watcher/decision_engine/strategy/context/base.py

@@ -18,14 +18,12 @@
 # limitations under the License.
 
 import abc
-import six
 
 from watcher import notifications
 from watcher.objects import fields
 
 
-@six.add_metaclass(abc.ABCMeta)
-class StrategyContext(object):
+class StrategyContext(object, metaclass=abc.ABCMeta):
 
     def execute_strategy(self, audit, request_context):
         """Execute the strategy for the given an audit

watcher/decision_engine/strategy/selection/base.py

@@ -17,11 +17,9 @@
 # limitations under the License.
 #
 import abc
-import six
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseSelector(object):
+class BaseSelector(object, metaclass=abc.ABCMeta):
 
     @abc.abstractmethod
     def select(self):

watcher/decision_engine/strategy/strategies/base.py

@@ -37,7 +37,6 @@ which are dynamically loaded by Watcher at launch time.
 """
 
 import abc
-import six
 
 from oslo_config import cfg
 from oslo_log import log
@@ -121,8 +120,7 @@ class StrategyEndpoint(object):
         return [available_datasource, available_metrics, available_cdm]
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseStrategy(loadable.Loadable):
+class BaseStrategy(loadable.Loadable, metaclass=abc.ABCMeta):
     """A base class for all the strategies
 
     A Strategy is an algorithm implementation which is able to find a
@@ -471,8 +469,7 @@ class BaseStrategy(loadable.Loadable):
                                  input_parameters=parameters)
 
 
-@six.add_metaclass(abc.ABCMeta)
-class DummyBaseStrategy(BaseStrategy):
+class DummyBaseStrategy(BaseStrategy, metaclass=abc.ABCMeta):
 
     @classmethod
     def get_goal_name(cls):
@@ -485,8 +482,7 @@ class DummyBaseStrategy(BaseStrategy):
         return []
 
 
-@six.add_metaclass(abc.ABCMeta)
-class UnclassifiedStrategy(BaseStrategy):
+class UnclassifiedStrategy(BaseStrategy, metaclass=abc.ABCMeta):
     """This base class is used to ease the development of new strategies
 
     The goal defined within this strategy can be used to simplify the
@@ -500,8 +496,7 @@ class UnclassifiedStrategy(BaseStrategy):
         return "unclassified"
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ServerConsolidationBaseStrategy(BaseStrategy):
+class ServerConsolidationBaseStrategy(BaseStrategy, metaclass=abc.ABCMeta):
 
     REASON_FOR_DISABLE = 'watcher_disabled'
 
@@ -510,16 +505,14 @@ class ServerConsolidationBaseStrategy(BaseStrategy):
         return "server_consolidation"
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ThermalOptimizationBaseStrategy(BaseStrategy):
+class ThermalOptimizationBaseStrategy(BaseStrategy, metaclass=abc.ABCMeta):
 
     @classmethod
     def get_goal_name(cls):
         return "thermal_optimization"
 
 
-@six.add_metaclass(abc.ABCMeta)
-class WorkloadStabilizationBaseStrategy(BaseStrategy):
+class WorkloadStabilizationBaseStrategy(BaseStrategy, metaclass=abc.ABCMeta):
 
     def __init__(self, *args, **kwargs):
         super(WorkloadStabilizationBaseStrategy, self
@@ -531,16 +524,14 @@ class WorkloadStabilizationBaseStrategy(BaseStrategy):
         return "workload_balancing"
 
 
-@six.add_metaclass(abc.ABCMeta)
-class NoisyNeighborBaseStrategy(BaseStrategy):
+class NoisyNeighborBaseStrategy(BaseStrategy, metaclass=abc.ABCMeta):
 
     @classmethod
     def get_goal_name(cls):
         return "noisy_neighbor"
 
 
-@six.add_metaclass(abc.ABCMeta)
-class SavingEnergyBaseStrategy(BaseStrategy):
+class SavingEnergyBaseStrategy(BaseStrategy, metaclass=abc.ABCMeta):
 
     @classmethod
     def get_goal_name(cls):
@@ -553,8 +544,7 @@ class SavingEnergyBaseStrategy(BaseStrategy):
         return []
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ZoneMigrationBaseStrategy(BaseStrategy):
+class ZoneMigrationBaseStrategy(BaseStrategy, metaclass=abc.ABCMeta):
 
     @classmethod
     def get_goal_name(cls):
@@ -567,8 +557,7 @@ class ZoneMigrationBaseStrategy(BaseStrategy):
         return []
 
 
-@six.add_metaclass(abc.ABCMeta)
-class HostMaintenanceBaseStrategy(BaseStrategy):
+class HostMaintenanceBaseStrategy(BaseStrategy, metaclass=abc.ABCMeta):
 
     REASON_FOR_MAINTAINING = 'watcher_maintaining'
 

watcher/decision_engine/strategy/strategies/vm_workload_consolidation.py

@@ -19,7 +19,6 @@
 #
 
 from oslo_log import log
-import six
 
 from watcher._i18n import _
 from watcher.common import exception
@@ -132,7 +131,7 @@ class VMWorkloadConsolidation(base.ServerConsolidationBaseStrategy):
 
         :param instance:
         """
-        if isinstance(instance.state, six.string_types):
+        if isinstance(instance.state, str):
             return instance.state
         elif isinstance(instance.state, element.InstanceState):
             return instance.state.value
@@ -148,7 +147,7 @@ class VMWorkloadConsolidation(base.ServerConsolidationBaseStrategy):
 
         :param node:
         """
-        if isinstance(node.status, six.string_types):
+        if isinstance(node.status, str):
             return node.status
         elif isinstance(node.status, element.ServiceState):
             return node.status.value

watcher/decision_engine/strategy/strategies/zone_migration.py

@@ -13,7 +13,6 @@
 #
 
 from dateutil.parser import parse
-import six
 
 from oslo_log import log
 
@@ -282,7 +281,7 @@ class ZoneMigration(base.ZoneMigrationBaseStrategy):
         action_counter = ActionCounter(total_limit,
                                        per_pool_limit, per_node_limit)
 
-        for k, targets in six.iteritems(filtered_targets):
+        for k, targets in iter(filtered_targets.items()):
             if k == VOLUME:
                 self.volumes_migration(targets, action_counter)
             elif k == INSTANCE:
@@ -580,7 +579,7 @@ class ZoneMigration(base.ZoneMigrationBaseStrategy):
         filter_list = []
         priority_filter_map = self.get_priority_filter_map()
 
-        for k, v in six.iteritems(self.priority):
+        for k, v in iter(self.priority.items()):
             if k in priority_filter_map:
                 filter_list.append(priority_filter_map[k](v))
 
@@ -710,7 +709,7 @@ class BaseFilter(object):
             return {}
 
         for cond in list(reversed(self.condition)):
-            for k, v in six.iteritems(targets):
+            for k, v in iter(targets.items()):
                 if not self.is_allowed(k):
                     continue
                 LOG.debug("filter:%s with the key: %s", cond, k)

watcher/decision_engine/threading.py

@@ -19,7 +19,6 @@
 import copy
 import futurist
 from futurist import waiters
-import six
 
 from oslo_config import cfg
 from oslo_log import log
@@ -29,8 +28,7 @@ CONF = cfg.CONF
 LOG = log.getLogger(__name__)
 
 
-@six.add_metaclass(service.Singleton)
-class DecisionEngineThreadPool(object):
+class DecisionEngineThreadPool(object, metaclass=service.Singleton):
     """Singleton threadpool to submit general tasks to"""
 
     def __init__(self):

watcher/objects/fields.py

@@ -15,7 +15,6 @@
 """Utility methods for objects"""
 
 import ast
-import six
 
 from oslo_serialization import jsonutils
 from oslo_versionedobjects import fields
@@ -67,7 +66,7 @@ class ListOfUUIDsField(fields.AutoTypedField):
 class FlexibleDict(fields.FieldType):
     @staticmethod
     def coerce(obj, attr, value):
-        if isinstance(value, six.string_types):
+        if isinstance(value, str):
             value = ast.literal_eval(value)
         return dict(value)
 
@@ -87,7 +86,7 @@ class FlexibleDictField(fields.AutoTypedField):
 class FlexibleListOfDict(fields.FieldType):
     @staticmethod
     def coerce(obj, attr, value):
-        if isinstance(value, six.string_types):
+        if isinstance(value, str):
             value = ast.literal_eval(value)
         return list(value)
 
@@ -106,7 +105,7 @@ class FlexibleListOfDictField(fields.AutoTypedField):
 
 class Json(fields.FieldType):
     def coerce(self, obj, attr, value):
-        if isinstance(value, six.string_types):
+        if isinstance(value, str):
             loaded = jsonutils.loads(value)
             return loaded
         return value

watcher/tests/api/base.py

@@ -24,11 +24,11 @@
 
 import copy
 import mock
+from urllib import parse as urlparse
 
 from oslo_config import cfg
 import pecan
 import pecan.testing
-from six.moves.urllib import parse as urlparse
 
 from watcher.api import hooks
 from watcher.common import context as watcher_context

watcher/tests/api/v1/test_audit_templates.py

@@ -13,12 +13,12 @@
 import datetime
 import itertools
 import mock
+from urllib import parse as urlparse
 from webtest.app import AppError
 
 from oslo_config import cfg
 from oslo_serialization import jsonutils
 from oslo_utils import timeutils
-from six.moves.urllib import parse as urlparse
 from wsme import types as wtypes
 
 from watcher.api.controllers.v1 import audit_template as api_audit_template

watcher/tests/api/v1/test_audits.py

@@ -14,13 +14,13 @@ import datetime
 from dateutil import tz
 import itertools
 import mock
+from urllib import parse as urlparse
 
 from oslo_config import cfg
 from oslo_serialization import jsonutils
 from oslo_utils import timeutils
 from wsme import types as wtypes
 
-from six.moves.urllib import parse as urlparse
 from watcher.api.controllers.v1 import audit as api_audit
 from watcher.common import utils
 from watcher.db import api as db_api

watcher/tests/api/v1/test_goals.py

@@ -12,7 +12,7 @@
 
 from oslo_config import cfg
 from oslo_serialization import jsonutils
-from six.moves.urllib import parse as urlparse
+from urllib import parse as urlparse
 
 from watcher.common import utils
 from watcher.tests.api import base as api_base

watcher/tests/api/v1/test_services.py

@@ -12,7 +12,7 @@
 
 from oslo_config import cfg
 from oslo_serialization import jsonutils
-from six.moves.urllib import parse as urlparse
+from urllib import parse as urlparse
 
 from watcher.tests.api import base as api_base
 from watcher.tests.objects import utils as obj_utils

watcher/tests/api/v1/test_strategies.py

@@ -11,10 +11,10 @@
 #    limitations under the License.
 
 import mock
+from urllib import parse as urlparse
 
 from oslo_config import cfg
 from oslo_serialization import jsonutils
-from six.moves.urllib import parse as urlparse
 
 from watcher.common import utils
 from watcher.decision_engine import rpcapi as deapi

watcher/tests/applier/workflow_engine/test_default_workflow_engine.py

@@ -19,8 +19,6 @@
 import abc
 import mock
 
-import six
-
 from watcher.applier.actions import base as abase
 from watcher.applier.actions import factory
 from watcher.applier.workflow_engine import default as tflow
@@ -36,8 +34,7 @@ class ExpectedException(Exception):
     pass
 
 
-@six.add_metaclass(abc.ABCMeta)
-class FakeAction(abase.BaseAction):
+class FakeAction(abase.BaseAction, metaclass=abc.ABCMeta):
     def schema(self):
         pass