daemonize

daemonize is a library for writing system daemons in Python. It is distributed under MIT license. Latest version can be downloaded from PyPI. Full documentation can be found at ReadTheDocs.

Dependencies

It is tested under following Python versions:

• 2.6
• 2.7
• 3.3
• 3.4
• 3.5

Installation

You can install it from Python Package Index (PyPI):

$ pip install daemonize

Usage

from time import sleep
from daemonize import Daemonize

pid = "/tmp/test.pid"


def main():
    while True:
        sleep(5)

daemon = Daemonize(app="test_app", pid=pid, action=main)
daemon.start()

File descriptors

Daemonize object's constructor understands the optional argument keep_fds which contains a list of FDs which should not be closed. For example:

import logging
from daemonize import Daemonize

pid = "/tmp/test.pid"
logger = logging.getLogger(__name__)
logger.setLevel(logging.DEBUG)
logger.propagate = False
fh = logging.FileHandler("/tmp/test.log", "w")
fh.setLevel(logging.DEBUG)
logger.addHandler(fh)
keep_fds = [fh.stream.fileno()]


def main():
    logger.debug("Test")

daemon = Daemonize(app="test_app", pid=pid, action=main, keep_fds=keep_fds)
daemon.start()