我如何将GAE作为后台服务运行

Question

I found a init.d script template -- filled in the blanks and tried to invoke GAE using something like:

start-stop-daemon -S --background python
/opt/google_appengine/dev_appserver.py --host=0.0.0.0
--admin_host=0.0.0.0 --php_executable_path=/usr/bin/php-cgi /var/www

This doesn't work...but if I run from the command line works fine but hangs the input...

How do I invoke this command at startup using init.d and change to the user "gae" -- similar to Apache runs as www-data

Answer 1

I also (briefly) tried to use start-stop-daemon to control Google App Engine (without any luck), so I ended up using /etc/rc.local to launch the daemon.

Add the following to /etc/rc.local (before any exit command):

sudo -i -u gae python /opt/google_appengine/dev_appserver.py --host=0.0.0.0 \
        --storage_path /var/cache/appengine/gae \
        --admin_host=0.0.0.0 --php_executable_path=/usr/bin/php-cgi /var/www > /dev/null 2> /dev/null &

Note , I included a storage_path in the launch options. Make sure you do the following:

sudo mkdir -p /var/cache/appengine/gae
sudo chown gae: /var/cache/appengine/gae

To restart the process (after an update), I just kill python and manually execute rc.local:

sudo killall -9 python
sudo /etc/rc.local

Answer 2

I have finally figured out how and why the start-stop-daemon was not working...it all boiled down to some simple syntactical errors and a (still?) misunderstanding on my behalf:

https://unix.stackexchange.com/questions/154692/start-stop-daemon-wont-start-my-python-script-as-service

In brief, when I use this init.d script and register it accordingly, GAE starts and stops accordingly:

#!/bin/sh
### BEGIN INIT INFO
# Provides:          Google App Engine daemon management
# Required-Start:    
# Required-Stop:     
# Default-Start:     
# Default-Stop:      
# Short-Description: Google App Engine initscript
# Description:       Start/stop appengine web server

### END INIT INFO

# Author: Alex Barylski <alex.barylski@gmail.com>

. /lib/lsb/init-functions

#
# Initialize variables
#

name=appengine
desc="Google App Engine"

bind=0.0.0.0

docroot=/var/www
phpexec=/usr/bin/php-cgi

pidfile=/var/run/$name.pid

args="--host=$bind --admin_host=$bind --php_executable_path=$phpexec"
prog='/usr/bin/python /opt/google_appengine/dev_appserver.py'

#
# TODO: Figure out how to switch user (ie: --chuid www-data)
#

case "${1}" in
   start)
      echo "Starting...$desc"
      start-stop-daemon --start --make-pidfile --background --oknodo \
                        --pidfile $pidfile \
                        --name $name \
                        --exec $prog \
                        -- $args $docroot 
      ;;

   stop)
      echo "Stopping...$desc"
      start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $prog
      ;;

   restart)
      ${0} stop
      sleep 1
      ${0} start
      ;;

   *)
      echo "Usage: ${0} {start|stop|restart}"
      exit 1
      ;;
esac

exit 0

I cannot figure out how to start the service as www-data and I am sure I could make this script more robust but for development purposes it is sufficient and runs as a daemon.

Hope this helps someone in the future, Alex