metronome: Auto-enable/disable metronome if there's no/at least one domain configured for XMPP

hooks/conf_regen/12-metronome

@@ -74,8 +74,22 @@ do_post_regen() {
     chown -R metronome: /var/lib/metronome/
     chown -R metronome: /etc/metronome/conf.d/
 
-    [[ -z "$regen_conf_files" ]] \
-        || systemctl restart metronome
+    if [[ -z "$(ls /etc/metronome/conf.d/*.cfg.lua 2>/dev/null)" ]]
+    then
+        if systemctl is-enabled metronome &>/dev/null
+        then
+            systemctl disable metronome --now 2>/dev/null
+        fi
+    else
+        if ! systemctl is-enabled metronome &>/dev/null
+        then
+            systemctl enable metronome --now 2>/dev/null
+            sleep 3
+        fi
+
+        [[ -z "$regen_conf_files" ]] \
+            || systemctl restart metronome
+    fi
 }
 
 do_$1_regen ${@:2}

src/service.py

@@ -712,6 +712,10 @@ def _get_services():
             "category": "web",
         }
 
+    # Ignore metronome entirely if XMPP was disabled on all domains
+    if "metronome" in services and not glob("/etc/metronome/conf.d/*.cfg.lua"):
+        del services["metronome"]
+
     # Remove legacy /var/log/daemon.log and /var/log/syslog from log entries
     # because they are too general. Instead, now the journalctl log is
     # returned by default which is more relevant.