Fully use futurist code-base to abstract concurrent.futures away

Change-Id: Iafa789f20d1ac365fe9da2ede2b2fa03a3b8720f

oslo_messaging/_executors/impl_pooledexecutor.py

@@ -15,10 +15,9 @@
 #    under the License.
 
 import collections
-import functools
 import threading
 
-from concurrent import futures
+from futurist import waiters
 from oslo_config import cfg
 from oslo_utils import excutils
 
@@ -54,8 +53,7 @@ class PooledExecutor(base.ExecutorBase):
     _executor_cls = None
 
     # Blocking function that should wait for all provided futures to finish.
-    _wait_for_all = functools.partial(futures.wait,
-                                      return_when=futures.ALL_COMPLETED)
+    _wait_for_all = staticmethod(waiters.wait_for_all)
 
     def __init__(self, conf, listener, dispatcher):
         super(PooledExecutor, self).__init__(conf, listener, dispatcher)

requirements.txt

@@ -37,18 +37,6 @@ kombu>=3.0.7
 # middleware
 oslo.middleware>=2.4.0 # Apache-2.0
 
-# FIXME: concurrent.futures is part of the Python stdlib since Python 3.2,
-# but the requirements is still needed because of a bug in tox:
-# https://bitbucket.org/hpk42/tox/issue/236/tox-must-create-the-source-distribution
-#
-# Tox builds a source distribution with "python setup.py sdist" which uses
-# requirements.txt even if tox wants to build the py34 virtual environment.
-# As a consequence, oslo.messaging.egg_info/requires.txt contains futures
-# and oslo_messaging.tests.test_opts.OptsTestCase.test_entry_point fails.
-#
-# for the futures based executor
-futures>=3.0;python_version=='2.7' or python_version=='2.6'
-
 # needed by the aioeventlet executor
 aioeventlet>=0.4
 trollius>=1.0