Remove use of six

nodepool is python3 only now, so there is no need to continue to use the
six library. Remove its use and shift to just using python3 versions of
things.

Change-Id: Ic1d1b4b736deba1b8325adf0b446e2121eaa6b20

nodepool/driver/__init__.py

@@ -25,8 +25,6 @@ import os
 import time
 import threading
 
-import six
-
 from kazoo import exceptions as kze
 
 from nodepool import zk
@@ -107,8 +105,7 @@ class Drivers:
             raise RuntimeError("%s: unknown driver" % name)
 
 
-@six.add_metaclass(abc.ABCMeta)
-class Provider(object):
+class Provider(object, metaclass=abc.ABCMeta):
     """The Provider interface
 
     The class or instance attribute **name** must be provided as a string.
@@ -147,8 +144,7 @@ class Provider(object):
         pass
 
 
-@six.add_metaclass(abc.ABCMeta)
-class NodeRequestHandler(object):
+class NodeRequestHandler(object, metaclass=abc.ABCMeta):
     '''
     Class to process a single nodeset request.
 
@@ -707,8 +703,7 @@ class Driver(ConfigValue):
     pass
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ProviderConfig(ConfigValue):
+class ProviderConfig(ConfigValue, metaclass=abc.ABCMeta):
     """The Provider config interface
 
     The class or instance attribute **name** must be provided as a string.

nodepool/task_manager.py

@@ -18,9 +18,8 @@
 
 import sys
 import threading
-import six
-from six.moves import queue as Queue
 import logging
+import queue
 import time
 import requests.exceptions
 
@@ -51,7 +50,7 @@ class Task(object):
     def wait(self):
         self._wait_event.wait()
         if self._exception:
-            six.reraise(self._exception, None, self._traceback)
+            raise self._exception.with_traceback(self._traceback)
         return self._result
 
     def run(self, client):
@@ -69,7 +68,7 @@ class TaskManager(threading.Thread):
     def __init__(self, client, name, rate):
         super(TaskManager, self).__init__(name=name)
         self.daemon = True
-        self.queue = Queue.Queue()
+        self.queue = queue.Queue()
         self._running = True
         self.name = name
         self.rate = float(rate)

nodepool/tests/test_webapp.py

@@ -16,7 +16,7 @@
 import json
 import logging
 import yaml
-from six.moves.urllib import request
+from urllib import request
 
 from nodepool import tests
 from nodepool import zk

nodepool/zk.py

@@ -17,7 +17,6 @@ from copy import copy
 import abc
 import json
 import logging
-import six
 import time
 from kazoo.client import KazooClient, KazooState
 from kazoo import exceptions as kze
@@ -204,7 +203,7 @@ class BaseModel(Serializable):
 
     @id.setter
     def id(self, value):
-        if not isinstance(value, six.string_types):
+        if not isinstance(value, str):
             raise TypeError("'id' attribute must be a string type")
         self._id = value
 

requirements.txt

@@ -7,8 +7,6 @@ extras
 statsd>=3.0
 sqlalchemy>=0.8.2,<1.1.0
 PrettyTable>=0.6,<0.8
-# shade has a looser requirement on six than nodepool, so install six first
-six>=1.7.0
 os-client-config>=1.2.0
 shade>=1.21.0
 diskimage-builder>=2.0.0