Merge ~hloeung/charm-telegraf:master into charm-telegraf:master

[Haw Loeung]

Add showing charm source version/commit in juju status output

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

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

[Joe Guo (guoqiao)]

LGTM, +1.

review: Approve

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

Change successfully merged at revision dabf651354e26000f980d63f4ffb1bf2e4f71d81

diff --git a/src/reactive/telegraf.py b/src/reactive/telegraf.py
index c139276..017ad67 100644
--- a/src/reactive/telegraf.py
+++ b/src/reactive/telegraf.py
@@ -1415,7 +1415,17 @@ def start_or_restart():
         time.sleep(0.1)
 
     if host.service_running(service):
-        hookenv.status_set("active", "Monitoring {}".format(get_remote_unit_name()))
+        revision = ''
+        if os.path.exists('version'):
+            with open('version') as f:
+                line = f.readline().strip()
+            # We only want the first 8 characters, that's enough to tell
+            # which version of the charm we're using.
+            if len(line) > 8:
+                revision = ' (source version/commit {}…)'.format(line[:8])
+            else:
+                revision = ' (source version/commit {})'.format(line)
+        hookenv.status_set("active", "Monitoring {}{}".format(get_remote_unit_name(), revision))
         clear_flag("telegraf.needs_reload")
     else:
         hookenv.status_set("blocked", "Telegraf failed to start. Check config.")