Wrapper script for running a Yesod app (xmlittre) as a daemon. start-stop-daemon starts the process, fork it in the background, and creates the PID file.

littre-daemon.sh

#! /bin/sh

DAEMON=xmlittre
NAME=xmlittre-web
DESC=xmlittre-web

MAINDIR=$(readlink -f `dirname "$0"`)
PIDPATH="$MAINDIR/tmp/run"
START_OPTS="--make-pidfile --background --no-close --chdir $MAINDIR"
DAEMON_OPTS="production --port 3000"

LOGPATH="$MAINDIR/tmp/log"
LOG="$LOGPATH/access.log"
LOG_ERR="$LOGPATH/error.log"

DAEMON="$MAINDIR/$DAEMON"
test -e $DAEMON || DAEMON="$MAINDIR/dist/build/xmlittre/xmlittre"
test -x $DAEMON || exit 0

test -e $LOGPATH || mkdir -p $LOGPATH || exit 1
test -e $PIDPATH || mkdir -p $PIDPATH || exit 1

set -e

. /lib/lsb/init-functions

daemon_start () {
	start-stop-daemon --start --pidfile $PIDPATH/$NAME.pid \
		--exec $DAEMON $START_OPTS -- $DAEMON_OPTS >> $LOG 2>> $LOG_ERR || true
}

daemon_stop () {
	start-stop-daemon --stop --pidfile $PIDPATH/$NAME.pid \
		--exec $DAEMON && rm "$PIDPATH/$NAME.pid"
}


case "$1" in
  start)
	echo -n "Starting $DESC: "
	echo -n "Starting $DESC: " >> $LOG
	daemon_start
	echo "$NAME."
	;;
  stop)
	echo -n "Stopping $DESC: "
	echo -n "Stopping $DESC: " >> $LOG
	daemon_stop
	echo "$NAME."
	;;
  restart|force-reload)
	echo -n "Restarting $DESC: "
	echo -n "Restarting $DESC: " >> $LOG
	daemon_stop
	sleep 1
	daemon_start
	echo "$NAME."
	;;
  status)
	status_of_proc -p $PIDPATH/$NAME.pid "$DAEMON" xmlittre && exit 0 || exit $?
	;;
  *)
	echo "Usage: $NAME {start|stop|restart|status}" >&2
	exit 1
	;;
esac

exit 0