Merge lp:~cjwatson/turku/turku-agent-fix-rsyncd-interaction into lp:turku/turku-agent

[Colin Watson]

On Upstart, check if turku-agent-rsyncd is already running before starting it.

This should fix the problem described in the history of https://code.launchpad.net/~cjwatson/turku/turku-agent-fix-rsyncd-interaction/+merge/367418.

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

[Haw Loeung (hloeung)]

LGTM, +1

review: Approve

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Change successfully merged at revision 51

=== modified file 'turku_agent/update_config.py'
--- turku_agent/update_config.py	2019-05-14 14:53:36 +0000
+++ turku_agent/update_config.py	2019-05-23 14:19:32 +0000
@@ -89,11 +89,30 @@
         f.write(built_rsyncd_secrets)
 
 
+def init_is_upstart():
+    try:
+        return 'upstart' in subprocess.check_output(
+            ['initctl', 'version'],
+            stderr=subprocess.DEVNULL, universal_newlines=True)
+    except (FileNotFoundError, subprocess.CalledProcessError):
+        return False
+
+
 def start_services():
     # Start rsyncd if it isn't already running.
     # Note that we do *not* need to reload rsyncd when changing rsyncd.conf,
     # as it rereads it on every client connection; but we may need to start
     # it as it won't start if its configuration file doesn't exist.
+    if init_is_upstart():
+        # With Upstart, start will fail if the service is already running,
+        # so we need to check for that first.
+        try:
+            if 'start/running' in subprocess.check_output(
+                    ['status', 'turku-agent-rsyncd'],
+                    stderr=subprocess.STDOUT, universal_newlines=True):
+                return
+        except subprocess.CalledProcessError:
+            pass
     subprocess.check_call(['service', 'turku-agent-rsyncd', 'start'])