Upstart script to launch a nodejs application as a service

nodejs-app.conf

description "Upstart script to run a nodejs app as a service"
author "Louis Chatriot"

env NODE_BIN=/usr/local/bin/node
env APP_DIR=/path/to/app/dir
env SCRIPT_FILE="scriptfile.js"   # Entry point for the nodejs app
env LOG_FILE=/path/to/logfile.log
env RUN_AS="anyuser"        # Upstart can only be run nicely as root, need to drop privileges
env SERVER_ENV="anything"   # Usual apps can be run in different environments (development, test, production ...)
                            # I typically use the environment variable NODE_ENV (see below) 
                            # If not needed simply remove the "NODE_ENV=$SERVER_ENV" below

# Start service on startup, stop on shutdown
start on runlevel [2345]
stop on runlevel [016]

# Respawn in case of a crash, with default parameters
respawn

script
        # Make sure logfile exists and can be written by the user we drop privileges to
	touch $LOG_FILE
	chown $RUN_AS:$RUN_AS $LOG_FILE

	chdir $APP_DIR

	NODE_ENV=$SERVER_ENV su -s /bin/sh -c 'exec "$0" "$@"' $RUN_AS -- $NODE_BIN $SCRIPT_FILE >> $LOG_FILE 2>&1
end script


post-start script
	echo "===== App restarted =====" >> $LOG_FILE
end script

Pretty simple Upstart script (as with all Upstart scripts) we use to run our different nodejs applications as a service. Note that the privilege drop cannot be achieved with a sudo -u within an Upstart script (I don't remember the reason). Moreover, future versions of Upstart will support running a service directly as a specific user.

thank you