Use systemd-run(1) in restart.sh

systemd-run(1) runs `systemctl restart` in an isolated systemd unit
that is not subject to process termination as jellyfin.service is shut
down. We adjust the sudoers configuration for this new usage, removing
the old config, since restart.sh is the only user of the sudoers
policy.

Additionally we change `systemctl start` to `systemctl restart` since
there was a race condition where jellyfin.service was not fully
stopped by the time this ran, so `systemctl start` became a noop.
`systemctl restart` on the other hand works whether jellyfin.service is
stopped or not.

The at(1) hack (and the usage of `start` instead of `restart`) is left
in for other init systems since I cannot test on those systems, and
because I don't know of any systemd-run(1) equivalent (although it may
be a non-issue since alternate init systems do not keep track of daemon
children nearly as aggressively as systemd does).

debian/bin/restart.sh

@@ -43,7 +43,8 @@ fi
 echo "Detected service control platform '$cmd'; using it to restart Jellyfin..."
 case $cmd in
     'systemctl')
-        echo "sleep 0.5; $sudo_command systemctl start jellyfin" | at now
+        # Without systemd-run here, `jellyfin.service`'s shutdown terminates this process too
+        $sudo_command systemd-run --scope systemctl restart jellyfin
         ;;
     'service')
         echo "sleep 0.5; $sudo_command service jellyfin start" | at now

debian/conf/jellyfin-sudoers

@@ -2,9 +2,9 @@
 Cmnd_Alias RESTARTSERVER_SYSV = /sbin/service jellyfin restart, /usr/sbin/service jellyfin restart
 Cmnd_Alias STARTSERVER_SYSV = /sbin/service jellyfin start, /usr/sbin/service jellyfin start
 Cmnd_Alias STOPSERVER_SYSV = /sbin/service jellyfin stop, /usr/sbin/service jellyfin stop
-Cmnd_Alias RESTARTSERVER_SYSTEMD = /usr/bin/systemctl restart jellyfin, /bin/systemctl restart jellyfin
-Cmnd_Alias STARTSERVER_SYSTEMD = /usr/bin/systemctl start jellyfin, /bin/systemctl start jellyfin
-Cmnd_Alias STOPSERVER_SYSTEMD = /usr/bin/systemctl stop jellyfin, /bin/systemctl stop jellyfin
+Cmnd_Alias RESTARTSERVER_SYSTEMD = /usr/bin/systemd-run --scope systemctl restart jellyfin
+Cmnd_Alias STARTSERVER_SYSTEMD = /usr/bin/systemd-run --scope systemctl start jellyfin
+Cmnd_Alias STOPSERVER_SYSTEMD = /usr/bin/systemd-run --scope systemctl stop jellyfin
 Cmnd_Alias RESTARTSERVER_INITD = /etc/init.d/jellyfin restart
 Cmnd_Alias STARTSERVER_INITD = /etc/init.d/jellyfin start
 Cmnd_Alias STOPSERVER_INITD = /etc/init.d/jellyfin stop

fedora/jellyfin.sudoers

@@ -1,8 +1,7 @@
 # Allow jellyfin group to start, stop and restart itself
-Cmnd_Alias RESTARTSERVER_SYSTEMD = /usr/bin/systemctl restart jellyfin, /bin/systemctl restart jellyfin
-Cmnd_Alias STARTSERVER_SYSTEMD = /usr/bin/systemctl start jellyfin, /bin/systemctl start jellyfin
-Cmnd_Alias STOPSERVER_SYSTEMD = /usr/bin/systemctl stop jellyfin, /bin/systemctl stop jellyfin
-
+Cmnd_Alias RESTARTSERVER_SYSTEMD = /usr/bin/systemd-run --scope systemctl restart jellyfin
+Cmnd_Alias STARTSERVER_SYSTEMD = /usr/bin/systemd-run --scope systemctl start jellyfin
+Cmnd_Alias STOPSERVER_SYSTEMD = /usr/bin/systemd-run --scope systemctl stop jellyfin
 
 jellyfin ALL=(ALL) NOPASSWD: RESTARTSERVER_SYSTEMD
 jellyfin ALL=(ALL) NOPASSWD: STARTSERVER_SYSTEMD

fedora/restart.sh

@@ -43,7 +43,8 @@ fi
 echo "Detected service control platform '$cmd'; using it to restart Jellyfin..."
 case $cmd in
     'systemctl')
-        echo "sleep 0.5; $sudo_command systemctl start jellyfin" | at now
+        # Without systemd-run here, `jellyfin.service`'s shutdown terminates this process too
+        $sudo_command systemd-run --scope systemctl restart jellyfin
         ;;
     'service')
         echo "sleep 0.5; $sudo_command service jellyfin start" | at now