Add pause/resume actions and sync charm-helpers

Adds pause and resume unit to the charm such that the
charm stays paused during maintenance operations.

Change-Id: I0b7185b5f865167b30b5c56ba4e133e049f7233d
Partial-Bug: 1558642

actions/actions.py

@@ -0,0 +1,48 @@
+#!/usr/bin/python
+
+import os
+import sys
+
+sys.path.append('hooks/')
+
+from charmhelpers.core.hookenv import action_fail
+from horizon_utils import (
+    pause_unit_helper,
+    resume_unit_helper,
+    register_configs,
+)
+
+
+def pause(args):
+    """Pause the Ceilometer services.
+    @raises Exception should the service fail to stop.
+    """
+    pause_unit_helper(register_configs())
+
+
+def resume(args):
+    """Resume the Ceilometer services.
+    @raises Exception should the service fail to start."""
+    resume_unit_helper(register_configs())
+
+
+# A dictionary of all the defined actions to callables (which take
+# parsed arguments).
+ACTIONS = {"pause": pause, "resume": resume}
+
+
+def main(args):
+    action_name = os.path.basename(args[0])
+    try:
+        action = ACTIONS[action_name]
+    except KeyError:
+        return "Action %s undefined" % action_name
+    else:
+        try:
+            action(args)
+        except Exception as e:
+            action_fail(str(e))
+
+
+if __name__ == "__main__":
+    sys.exit(main(sys.argv))

actions/pause

@@ -0,0 +1 @@
+actions.py

actions/resume

@@ -0,0 +1 @@
+actions.py