notify calling process we are ready to serve

Fixes bug 980037 again

Systemd notification should be sent in-process, otherwise systemd might
miss the subprocess sending notification.
See systemd bug https://bugzilla.redhat.com/show_bug.cgi?id=820448

Change-Id: Iccc51cf77af5598ee6b4c3cd69a12a7ee9fc2eb5

1 files changed, 8 insertions, 3 deletions

diff --git a/bin/keystone-all b/bin/keystone-all
index fc499967..c7734cf2 100755
--- a/bin/keystone-all
+++ b/bin/keystone-all
@@ -22,6 +22,7 @@ from paste import deploy
 from keystone import config
 from keystone.common import wsgi
 from keystone.common import utils
+from keystone.openstack.common import importutils
 
 
 CONF = config.CONF
@@ -54,9 +55,13 @@ def serve(*servers):
     # notify calling process we are ready to serve
     if CONF.onready:
         try:
-            utils.check_output(CONF.onready.split())
-        except Exception:
-            logging.exception('Failed to execute onready command')
+            notifier = importutils.import_module(CONF.onready)
+            notifier.notify()
+        except ImportError:
+            try:
+                utils.check_output(CONF.onready.split())
+            except Exception:
+                logging.exception('Failed to execute onready command')
 
     for server in servers:
         try: