eventlet workaround to avoid import cycle issue

Do get_hub() before monkey_patch() to workaround issue with
import cycles in eventlet < 0.22.0;
Based on the worked-around in eventlet with patch
b756447bab

Also reverts the test skipping that was done because of the issue.

Revert "temporarily skip local haht test under py27"
This reverts commit de2e4f1cfc.

Closes-Bug: 1746136
Closes-Bug: 1745112

Change-Id: I72c349e81dfc02136b22637c707ad4908c9f269e

congress/cfg_validator/agent/__init__.py

@@ -1,3 +1,9 @@
 # NOTE(ekcs): monkey_patch upfront to ensure all imports get patched modules
 import eventlet
+# NOTE(ekcs): get_hub() before monkey_patch() to workaround issue with
+# import cycles in eventlet < 0.22.0;
+# Based on the worked-around in eventlet with patch
+# https://github.com/eventlet/eventlet/commit/b756447bab51046dfc6f1e0e299cc997ab343701
+# For details please check https://bugs.launchpad.net/congress/+bug/1746136
+eventlet.hubs.get_hub()
 eventlet.monkey_patch()

congress/server/__init__.py

@@ -1,3 +1,9 @@
 # NOTE(ekcs): monkey_patch upfront to ensure all imports get patched modules
 import eventlet
+# NOTE(ekcs): get_hub() before monkey_patch() to workaround issue with
+# import cycles in eventlet < 0.22.0;
+# Based on the worked-around in eventlet with patch
+# https://github.com/eventlet/eventlet/commit/b756447bab51046dfc6f1e0e299cc997ab343701
+# For details please check https://bugs.launchpad.net/congress/+bug/1746136
+eventlet.hubs.get_hub()
 eventlet.monkey_patch()

congress/tests/__init__.py

@@ -1,3 +1,9 @@
 # NOTE(boden): patch upfront to ensure all imports get patched modules
 import eventlet
+# NOTE(ekcs): get_hub() before monkey_patch() to workaround issue with
+# import cycles in eventlet < 0.22.0;
+# Based on the worked-around in eventlet with patch
+# https://github.com/eventlet/eventlet/commit/b756447bab51046dfc6f1e0e299cc997ab343701
+# For details please check https://bugs.launchpad.net/congress/+bug/1746136
+eventlet.hubs.get_hub()
 eventlet.monkey_patch()

congress/tests/haht/test_congress_haht.py

@@ -31,7 +31,6 @@ import time
 
 from oslo_log import log as logging
 import requests
-import six
 import tenacity
 
 from congress.db import api as db
@@ -71,10 +70,6 @@ class TestCongressHAHT(base.SqlTestCase):
             return x
 
     def setUp(self):
-        # FIXME(ekcs): fix test and unskip
-        if six.PY2:
-            self.skipTest("Temporarily skip under python 2 while "
-                          "failure is being resolved.")
         super(TestCongressHAHT, self).setUp()
         assert sys.executable is not None,\
             'test cannot proceed when sys.executable is None'