Upstart is a ridiculously easy way to turn your scripts into daemons. Take this python script:
/home/myuser/ez_daemon.py
:
import time
while 1:
print("I'm a daemon!")
time.sleep(1)
We’re going to turn it into a daemon with a single line:
/etc/init/ez_daemon.conf
:
exec python /home/myuser/ez_daemon.py
And that’s it!
sudo start ez_daemon
sudo tail -f /var/log/upstart/ez_daemon.log
sudo stop ez_daemon
You can do this for any program, and it’s how Ubuntu and Fedora start most daemons.
Here’s a more complete example:
author "Graham King <graham@gkgk.org>"
description "uwsgi server for example.com"
start on (static-network-up and started mysql)
stop on shutdown
console log
respawn
respawn limit 10 5
setuid www-data
setgid www-data
env PYTHONPATH=/srv/example/src/example/
exec /srv/example/bin/uwsgi \
--virtualenv=/srv/example/ \
--module=example.django_wsgi \
--http=127.0.0.1:8001
Each line is called a stanza, and they are documented in the Upstart cookbook.
It’s clear, it’s easy, and it works. And that makes me happy.