Upstart script for restarting Node.js app when it exits unexpectedly

sitdown.conf

description "SitDown server running on node.js"

start on startup
stop on shutdown

# respawn (restart) automatically -- try only 10 times
respawn
respawn limit 10 10

script
    echo $$ > /var/run/sitdown.pid
    exec /usr/local/bin/node /usr/local/sitdown-installed-here/app.js >> /var/log/sitdown.log 2>&1
end script

pre-start script
    echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (sys) Starting" >> /var/log/sitdown.sys.log
    echo "SitDown service (re)started at `date +"%F %T.%N"`" | mail -s "SitDown Service Started" name@example.com
end script

pre-stop script
    rm /var/run/sitdown.pid
    echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (sys) Stopping" >> /var/log/sitdown.sys.log
    echo "SitDown service stopped at `date +"%F %T.%N"`" | mail -s "SitDown Service Stopped" name@example.com
end script

Thanks to http://howtonode.org/deploying-node-upstart-monit and http://kvz.io/blog/2009/12/15/run-nodejs-as-a-service-on-ubuntu-karmic/ and answers to questions on ServerFault: http://serverfault.com/questions/236925/how-can-i-receive-an-email-when-an-upstart-monitored-script-respawns?rq=1