Autostart service

I'm looking for a way to configure a service to run automatically whenever it stops for some reason. Currently I have set up a cronjob that checks if the service is running every minute and restarts it if it has crashed but that seems dull. How can I do this the right way?

I have added some questionable scripts to make the service work, you can see below

x@x:~$ sudo cat /etc/init.d/my-service
#!/bin/sh
### BEGIN INIT INFO
# Provides: my-service
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Start daemon at boot time
# Description:       Enable service provided by daemon.
### END INIT INFO

dir="/var/www/html/my-service"
cmd="nodejs chat.js"
user="www-data"

name=`basename $0`
pid_file="/var/run/$name.pid"
stdout_log="/var/log/$name.log"
stderr_log="/var/log/$name.err"

get_pid() {
    cat "$pid_file"
}

is_running() {
    [ -f "$pid_file" ] && ps `get_pid` > /dev/null 2>&1
}

case "$1" in
    start)
    if is_running; then
        echo "Already started"
    else
        echo "Starting $name"
        cd "$dir"
        if [ -z "$user" ]; then
            sudo $cmd >> "$stdout_log" 2>> "$stderr_log" &
        else
            sudo -u "$user" $cmd >> "$stdout_log" 2>> "$stderr_log" &
        fi
        echo $! > "$pid_file"
        if ! is_running; then
            echo "Unable to start, see $stdout_log and $stderr_log"
            exit 1
        fi
    fi
    ;;
    stop)
    if is_running; then
        echo -n "Stopping $name.."
        kill `get_pid`
        for i in {1..10}
        do
            if ! is_running; then
                break
            fi

            echo -n "."
            sleep 1
        done
        echo

        if is_running; then
            echo "Not stopped; may still be shutting down or shutdown may have f                                                                                                                               ailed"
            exit 1
        else
            echo "Stopped"
            if [ -f "$pid_file" ]; then
                rm "$pid_file"
            fi
        fi
    else
        echo "Not running"
    fi
    ;;
    restart)
    $0 stop
    if is_running; then
        echo "Unable to stop, will not attempt to start"
        exit 1
    fi
    $0 start
    ;;
    status)
    if is_running; then
        echo "Running"
    else
        echo "Stopped"
        exit 1
    fi
    ;;
    *)
    echo "Usage: $0 {start|stop|restart|status}"
    exit 1
    ;;
esac

exit 0

And also my-service.service

x@x:~$ cat /etc/systemd/system/my-service.service
[Unit]
Description=my-service daemon

[Service]
ExecStart=/usr/bin/nodejs /var/www/html/my-service/chat.js
Type=simple
User=root
Group=root
Restart=always

[Install]
WantedBy=multi-user.target

For example when the machine reboots I get this as status

Jan 24 10:54:41 x systemd[1]: my-service.service: Service hold-off time over, scheduling restart.
Jan 24 10:54:41 x systemd[1]: Stopped my-service daemon.
Jan 24 10:54:41 x systemd[1]: my-service.service: Start request repeated too quickly.
Jan 24 10:54:41 x systemd[1]: Failed to start my-service daemon.