Use flake8-import-order

Use the flake8 plugin flake8-import-order to check import ordering. It
can do it automatically and don't need reviewers to check it.

Change-Id: Ia3d81bbbb44b40804b3268c0e648276a36cb4805

nova/api/openstack/placement/handlers/resource_provider.py

@@ -12,8 +12,8 @@
 """Placement API handlers for resource providers."""
 
 import copy
-import jsonschema
 
+import jsonschema
 from oslo_db import exception as db_exc
 from oslo_serialization import jsonutils
 from oslo_utils import encodeutils

nova/api/openstack/placement/util.py

@@ -12,6 +12,7 @@
 """Utility methods for placement API."""
 
 import functools
+
 import jsonschema
 from oslo_middleware import request_id
 from oslo_serialization import jsonutils

nova/test.py

@@ -20,19 +20,19 @@ Allows overriding of flags for use of fakes, and some black magic for
 inline callbacks.
 
 """
-import contextlib
 
-import datetime
-import eventlet
+import eventlet  # noqa
 eventlet.monkey_patch(os=False)
 
+import contextlib
 import copy
+import datetime
 import inspect
-import mock
 import os
 import pprint
 
 import fixtures
+import mock
 from oslo_cache import core as cache
 from oslo_concurrency import lockutils
 from oslo_config import cfg

nova/tests/unit/api/openstack/placement/test_microversion.py

@@ -13,9 +13,10 @@
 """Tests for placement microversion handling."""
 
 import collections
-import mock
 import operator
 
+import mock
+
 # import the handlers to load up handler decorators
 import nova.api.openstack.placement.handler  # noqa
 from nova.api.openstack.placement import microversion

nova/tests/unit/volume/encryptors/test_cryptsetup.py

@@ -16,12 +16,12 @@
 
 import binascii
 import copy
+import uuid
 
 from castellan.common.objects import symmetric_key as key
 import mock
 from oslo_concurrency import processutils
 import six
-import uuid
 
 from nova import exception
 from nova.tests.unit.volume.encryptors import test_base

test-requirements.txt

@@ -6,6 +6,7 @@ hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
 coverage>=4.0 # Apache-2.0
 ddt>=1.0.1 # MIT
 fixtures>=3.0.0 # Apache-2.0/BSD
+flake8-import-order==0.11 # LGPLv3
 mock>=2.0 # BSD
 mox3!=0.19.0,>=0.7.0 # Apache-2.0
 psycopg2>=2.5 # LGPL/ZPL

tox.ini

@@ -157,6 +157,7 @@ commands = bash -c tools/releasenotes_tox.sh
 enable-extensions = H106,H203,H904
 ignore = E121,E122,E123,E124,E125,E126,E127,E128,E129,E131,E251,H405
 exclude =  .venv,.git,.tox,dist,doc,*lib/python*,*egg,build,tools/xenserver*,releasenotes
+import-order-style = pep8
 # To get a list of functions that are more complex than 25, set max-complexity
 # to 25 and run 'tox -epep8'.
 # 34 is currently the most complex thing we have