Remove all usage of six library

Replace six with Python 3 style code.

Change-Id: I3d0c35e237484409d8410601ec482fac0dacf30d

lower-constraints.txt

@@ -38,7 +38,6 @@ requests==2.14.2
 requests-mock==1.2.0
 requestsexceptions==1.2.0
 rfc3986==0.3.1
-six==1.10.0
 stestr==2.0.0
 smmap==0.9.0
 snowballstemmer==1.2.1

oslo_policy/_checks.py

@@ -19,7 +19,6 @@ import abc
 import ast
 import inspect
 
-import six
 import stevedore
 
 if hasattr(inspect, 'getfullargspec'):
@@ -86,8 +85,7 @@ def _check(rule, target, creds, enforcer, current_rule):
     return rule(*rule_args)
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseCheck(object):
+class BaseCheck(metaclass=abc.ABCMeta):
     """Abstract base class for Check classes."""
 
     @abc.abstractmethod
@@ -316,7 +314,7 @@ class GenericCheck(Check):
         '''
 
         if len(path_segments) == 0:
-            return match == six.text_type(test_value)
+            return match == str(test_value)
         key, path_segments = path_segments[0], path_segments[1:]
         try:
             test_value = test_value[key]
@@ -341,7 +339,7 @@ class GenericCheck(Check):
         try:
             # Try to interpret self.kind as a literal
             test_value = ast.literal_eval(self.kind)
-            return match == six.text_type(test_value)
+            return match == str(test_value)
 
         except ValueError:
             pass

oslo_policy/_parser.py

@@ -18,8 +18,6 @@
 import logging
 import re
 
-import six
-
 from oslo_policy import _checks
 
 
@@ -72,8 +70,7 @@ class ParseStateMeta(type):
         return super(ParseStateMeta, mcs).__new__(mcs, name, bases, cls_dict)
 
 
-@six.add_metaclass(ParseStateMeta)
-class ParseState(object):
+class ParseState(metaclass=ParseStateMeta):
     """Implement the core of parsing the policy language.
 
     Uses a greedy reduction algorithm to reduce a sequence of tokens into
@@ -246,7 +243,7 @@ def _parse_list_rule(rule):
             continue
 
         # Handle bare strings
-        if isinstance(inner_rule, six.string_types):
+        if isinstance(inner_rule, str):
             inner_rule = [inner_rule]
 
         # Parse the inner rules into Check objects
@@ -350,6 +347,6 @@ def parse_rule(rule):
     """Parses a policy rule into a tree of :class:`.Check` objects."""
 
     # If the rule is a string, it's in the policy language
-    if isinstance(rule, six.string_types):
+    if isinstance(rule, str):
         return _parse_text_rule(rule)
     return _parse_list_rule(rule)

oslo_policy/policy.py

@@ -231,7 +231,6 @@ from oslo_config import cfg
 from oslo_context import context
 from oslo_serialization import jsonutils
 from oslo_utils import strutils
-import six
 import yaml
 
 from oslo_policy import _cache_handler
@@ -387,7 +386,7 @@ def parse_file_contents(data):
         except yaml.YAMLError as e:
             # For backwards-compatibility, convert yaml error to ValueError,
             # which is what JSON loader raised.
-            raise ValueError(six.text_type(e))
+            raise ValueError(str(e))
     return parsed or {}
 
 
@@ -456,7 +455,7 @@ class Rules(dict):
         if self.default_rule not in self:
             raise KeyError(key)
 
-        elif isinstance(self.default_rule, six.string_types):
+        elif isinstance(self.default_rule, str):
             return self[self.default_rule]
 
     def __str__(self):
@@ -1176,7 +1175,7 @@ class RuleDefault(object):
             if not isinstance(scope_types, list):
                 raise ValueError(msg)
             for scope_type in scope_types:
-                if not isinstance(scope_type, six.string_types):
+                if not isinstance(scope_type, str):
                     raise ValueError(msg)
                 if scope_types.count(scope_type) > 1:
                     raise ValueError(

oslo_policy/tests/base.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 import codecs
+import io
 import os
 import os.path
 import sys
@@ -21,7 +22,6 @@ import sys
 import fixtures
 from oslo_config import fixture as config
 from oslotest import base as test_base
-from six import moves
 
 from oslo_policy import _checks
 from oslo_policy import policy
@@ -55,7 +55,7 @@ class PolicyBaseTestCase(test_base.BaseTestCase):
             f.write(contents)
 
     def _capture_stdout(self):
-        self.useFixture(fixtures.MonkeyPatch('sys.stdout', moves.StringIO()))
+        self.useFixture(fixtures.MonkeyPatch('sys.stdout', io.StringIO()))
         return sys.stdout
 
 

oslo_policy/tests/test_external.py

@@ -18,7 +18,7 @@ from unittest import mock
 
 from oslo_serialization import jsonutils
 from requests_mock.contrib import fixture as rm_fixture
-import six.moves.urllib.parse as urlparse
+from urllib import parse as urlparse
 
 from oslo_policy import _external
 from oslo_policy import opts

oslo_policy/tests/test_parser.py

@@ -16,7 +16,6 @@
 from unittest import mock
 
 from oslotest import base as test_base
-import six
 
 from oslo_policy import _checks
 from oslo_policy import _parser
@@ -173,8 +172,7 @@ class ParseStateMetaTestCase(test_base.BaseTestCase):
         self.assertEqual([['d', 'e', 'f'], ['a', 'b', 'c']], spam.reducers)
 
     def test_parse_state_meta(self):
-        @six.add_metaclass(_parser.ParseStateMeta)
-        class FakeState(object):
+        class FakeState(metaclass=_parser.ParseStateMeta):
 
             @_parser.reducer('a', 'b', 'c')
             @_parser.reducer('d', 'e', 'f')

oslo_policy/tests/test_policy.py

@@ -23,7 +23,6 @@ from oslo_config import cfg
 from oslo_context import context
 from oslo_serialization import jsonutils
 from oslotest import base as test_base
-import six
 
 from oslo_policy import _cache_handler
 from oslo_policy import _checks
@@ -349,8 +348,7 @@ class EnforcerTest(base.PolicyBaseTestCase):
         self.enforcer.load_rules(False)
         self.assertIsNotNone(self.enforcer.rules)
 
-        old = six.next(six.itervalues(
-            self.enforcer._policy_dir_mtimes))
+        old = next(iter(self.enforcer._policy_dir_mtimes))
         self.assertEqual(1, len(self.enforcer._policy_dir_mtimes))
 
         # Touch the file
@@ -361,8 +359,7 @@ class EnforcerTest(base.PolicyBaseTestCase):
 
         self.enforcer.load_rules(False)
         self.assertEqual(1, len(self.enforcer._policy_dir_mtimes))
-        self.assertEqual(old, six.next(six.itervalues(
-            self.enforcer._policy_dir_mtimes)))
+        self.assertEqual(old, next(iter(self.enforcer._policy_dir_mtimes)))
 
         loaded_rules = jsonutils.loads(str(self.enforcer.rules))
         self.assertEqual('is_admin:True', loaded_rules['admin'])
@@ -385,14 +382,12 @@ class EnforcerTest(base.PolicyBaseTestCase):
         self.enforcer.load_rules(False)
         self.assertIsNotNone(self.enforcer.rules)
 
-        old = six.next(six.itervalues(
-            self.enforcer._policy_dir_mtimes))
+        old = next(iter(self.enforcer._policy_dir_mtimes))
         self.assertEqual(1, len(self.enforcer._policy_dir_mtimes))
 
         self.enforcer.load_rules(False)
         self.assertEqual(1, len(self.enforcer._policy_dir_mtimes))
-        self.assertEqual(old, six.next(six.itervalues(
-            self.enforcer._policy_dir_mtimes)))
+        self.assertEqual(old, next(iter(self.enforcer._policy_dir_mtimes)))
 
         loaded_rules = jsonutils.loads(str(self.enforcer.rules))
         self.assertEqual('is_admin:True', loaded_rules['admin'])

requirements.txt

@@ -8,6 +8,5 @@ oslo.context>=2.22.0 # Apache-2.0
 oslo.i18n>=3.15.3 # Apache-2.0
 oslo.serialization!=2.19.1,>=2.18.0 # Apache-2.0
 PyYAML>=5.1 # MIT
-six>=1.10.0 # MIT
 stevedore>=1.20.0 # Apache-2.0
 oslo.utils>=3.40.0 # Apache-2.0