reloads mutable config values on SIGHUP

This changes the ironic (ironic-api and ironic-conductor)
services so that when a SIGHUP signal is issued, the
service reloads (and uses) the values of mutable configuration
options.

The mutable configuration options (set by oslo.config Opts' mutable=True)
are:
- [DEFAULT]/pin_release_version
- [DEFAULT]/debug
- [DEFAULT]/log_config_append
and are indicated as such in ironic's sample config
(https://docs.openstack.org/ironic/latest/configuration/sample-config.html)
by "# Note: This option can be changed without restarting.".

Configuration options are mutable if their oslo.config Opt's mutable=True
is set. This mutable setting is respected when the oslo method
mutate_config_files is called instead of reload_config_files.
Icec3e664f3fe72614e373b2938e8dee53cf8bc5e allows services to tell
oslo.service they want mutate_config_files to be called by specifying the
'restart_method=mutate' parameter, which this patch does.

Change-Id: I0df46bb21dda035b25daad17737dbfedb861e868
Closes-Bug: #1585595

1 files changed, 1 insertions, 1 deletions

diff --git a/ironic/common/service.py b/ironic/common/service.py
index a077889bb..e0a8f1852 100644
--- a/ironic/common/service.py
+++ b/ironic/common/service.py
@@ -36,4 +36,4 @@ def prepare_service(argv=None):
 
 
 def process_launcher():
-    return service.ProcessLauncher(CONF)
+    return service.ProcessLauncher(CONF, restart_method='mutate')