Switch the charm to support py3

Some major changes:
* the charm has been rebased (from a Python perspective) to be rooted in
  the charm directory.  This is a single root.
* Imports have been changed so that the don't add lots of imports to the
  namespace of the module doing the import.
* The code that used to run at module import time has been made lazy
  such that it only has to run if the relevant functions are called.
  This includes restart_on_change parameters, the harden function and
  the parameters to the guard_map.  Appropriate changes will be
  submitted to charm-helpers.
* Several tests had to be re-written as (incorrect) mocking meant that
  text fixtures didn't actually match what the code was doing.  Thus,
  the tests were meaningless.
* This has had a net positive impact on the unit tests wrt to importing
  modules and mocking.

Change-Id: Id07d9d1caaa9b29453a63c2e49ba831071e9457f

actions/actions.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python3
 #
 # Copyright 2016 Canonical Ltd
 #
@@ -17,40 +17,39 @@
 import os
 import sys
 
-sys.path.append('hooks/')
+_path = os.path.dirname(os.path.realpath(__file__))
+_root = os.path.abspath(os.path.join(_path, '..'))
 
-from charmhelpers.core.hookenv import (
-    action_fail,
-    action_get,
-    action_set,
-)
-from nova_cc_utils import (
-    pause_unit_helper,
-    resume_unit_helper,
-    register_configs,
-    archive_deleted_rows,
-)
+
+def _add_path(path):
+    if path not in sys.path:
+        sys.path.insert(1, path)
+
+_add_path(_root)
+
+import charmhelpers.core.hookenv as hookenv
+import hooks.nova_cc_utils as utils
 
 
 def pause(args):
     """Pause the Ceilometer services.
     @raises Exception should the service fail to stop.
     """
-    pause_unit_helper(register_configs())
+    utils.pause_unit_helper(utils.register_configs())
 
 
 def resume(args):
     """Resume the Ceilometer services.
     @raises Exception should the service fail to start."""
-    resume_unit_helper(register_configs())
+    utils.resume_unit_helper(utils.register_configs())
 
 
 def archive_data(args):
     """Run data archival process
     @raises Exception should the archival fail"""
-    action_set({
-        'archive-deleted-rows': archive_deleted_rows(
-            max_rows=action_get('batch-size'))})
+    hookenv.action_set({
+        'archive-deleted-rows': utils.archive_deleted_rows(
+            max_rows=hookenv.action_get('batch-size'))})
 
 
 # A dictionary of all the defined actions to callables (which take
@@ -71,7 +70,7 @@ def main(args):
         try:
             action(args)
         except Exception as e:
-            action_fail(str(e))
+            hookenv.action_fail(str(e))
 
 
 if __name__ == "__main__":

actions/openstack_upgrade.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python3
 #
 # Copyright 2016 Canonical Ltd
 #
@@ -14,28 +14,23 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import os
 import sys
 
-sys.path.append('hooks/')
+_path = os.path.dirname(os.path.realpath(__file__))
+_root = os.path.abspath(os.path.join(_path, '..'))
 
-from charmhelpers.contrib.openstack.utils import (
-    do_action_openstack_upgrade,
-)
 
-from charmhelpers.core.hookenv import (
-    relation_ids,
-)
+def _add_path(path):
+    if path not in sys.path:
+        sys.path.insert(1, path)
 
-from nova_cc_utils import (
-    do_openstack_upgrade,
-)
+_add_path(_root)
 
-from nova_cc_hooks import (
-    config_changed,
-    CONFIGS,
-    neutron_api_relation_joined,
-    db_joined,
-)
+import charmhelpers.contrib.openstack.utils as ch_utils
+import charmhelpers.core.hookenv as hookenv
+import hooks.nova_cc_utils as utils
+import hooks.nova_cc_hooks as hooks
 
 
 def openstack_upgrade():
@@ -46,16 +41,17 @@ def openstack_upgrade():
     code to run, otherwise a full service level upgrade will fire
     on config-changed."""
 
-    if (do_action_openstack_upgrade('nova-common',
-                                    do_openstack_upgrade,
-                                    CONFIGS)):
-        [neutron_api_relation_joined(rid=rid, remote_restart=True)
-            for rid in relation_ids('neutron-api')]
+    if (ch_utils.do_action_openstack_upgrade('nova-common',
+                                             utils.do_openstack_upgrade,
+                                             hooks.CONFIGS)):
+        for rid in hookenv.relation_ids('neutron-api'):
+            hooks.neutron_api_relation_joined(rid=rid, remote_restart=True)
         # NOTE(thedac): Force re-fire of shared-db joined hook
         # to ensure that nova_api database is setup if required.
-        [db_joined(relation_id=r_id)
-            for r_id in relation_ids('shared-db')]
-        config_changed()
+        for r_id in hookenv.relation_ids('shared-db'):
+            hooks.db_joined(relation_id=r_id)
+        hooks.config_changed()
 
 if __name__ == '__main__':
+    hooks.resolve_CONFIGS()
     openstack_upgrade()

charm-helpers-hooks.yaml

@@ -1,5 +1,5 @@
 repo: https://github.com/juju/charm-helpers
-destination: hooks/charmhelpers
+destination: charmhelpers
 include:
     - core
     - osplatform

charmhelpers/contrib/hardening/harden.py

@@ -27,6 +27,8 @@ from charmhelpers.contrib.hardening.ssh.checks import run_ssh_checks
 from charmhelpers.contrib.hardening.mysql.checks import run_mysql_checks
 from charmhelpers.contrib.hardening.apache.checks import run_apache_checks
 
+_DISABLE_HARDENING_FOR_UNIT_TEST = False
+
 
 def harden(overrides=None):
     """Hardening decorator.
@@ -48,9 +50,18 @@ def harden(overrides=None):
     :returns: Returns value returned by decorated function once executed.
     """
     def _harden_inner1(f):
-        log("Hardening function '%s'" % (f.__name__), level=DEBUG)
+        # As this has to be py2.7 compat, we can't use nonlocal.  Use a trick
+        # to capture the dictionary that can then be updated.
+        _logged = {'done': False}
 
         def _harden_inner2(*args, **kwargs):
+            # knock out hardening via a config var; normally it won't get
+            # disabled.
+            if _DISABLE_HARDENING_FOR_UNIT_TEST:
+                return f(*args, **kwargs)
+            if not _logged['done']:
+                log("Hardening function '%s'" % (f.__name__), level=DEBUG)
+                _logged['done'] = True
             RUN_CATALOG = OrderedDict([('os', run_os_checks),
                                        ('ssh', run_ssh_checks),
                                        ('mysql', run_mysql_checks),