Python 脚本作为 linux 服务/守护进程 [英] Python script as linux service/daemon

问题描述

你好，

我试图让 python 脚本作为服务(守护进程)在 (ubuntu) linux 上运行.

I'm trying to let a python script run as service (daemon) on (ubuntu) linux.

在网络上有几种解决方案，例如:

On the web there exist several solutions like:

http://pypi.python.org/pypi/python-daemon/

一个行为良好的 Unix 守护进程很难做到正确，但每个守护程序所需的步骤都大同小异.DaemonContext 实例保存程序的行为和配置的进程环境；将该实例用作上下文管理器以进入守护程序状态.

A well-behaved Unix daemon process is tricky to get right, but the required steps are much the same for every daemon program. A DaemonContext instance holds the behaviour and configured process environment for the program; use the instance as a context manager to enter a daemon state.

http://www.jejik.com/articles/2007/02/a_simple_unix_linux_daemon_in_python/

但是，因为我想将我的 python 脚本专门与 ubuntu linux 集成，所以我的解决方案是与 init.d 脚本相结合

However as I want to integrate my python script specifically with ubuntu linux my solution is a combination with an init.d script

#!/bin/bash

WORK_DIR="/var/lib/foo"
DAEMON="/usr/bin/python"
ARGS="/opt/foo/linux_service.py"
PIDFILE="/var/run/foo.pid"
USER="foo"

case "$1" in
  start)
    echo "Starting server"
    mkdir -p "$WORK_DIR"
    /sbin/start-stop-daemon --start --pidfile $PIDFILE 
        --user $USER --group $USER 
        -b --make-pidfile 
        --chuid $USER 
        --exec $DAEMON $ARGS
    ;;
  stop)
    echo "Stopping server"
    /sbin/start-stop-daemon --stop --pidfile $PIDFILE --verbose
    ;;
  *)
    echo "Usage: /etc/init.d/$USER {start|stop}"
    exit 1
    ;;
esac

exit 0

在 python 中:

and in python:

import signal
import time
import multiprocessing

stop_event = multiprocessing.Event()

def stop(signum, frame):
    stop_event.set()

signal.signal(signal.SIGTERM, stop)

if __name__ == '__main__':
    while not stop_event.is_set():
        time.sleep(3)

我现在的问题是这种方法是否正确.我是否必须处理任何额外的信号?它会是一个行为良好的 Unix 守护进程"吗?

My question now is if this approach is correct. Do I have to handle any additional signals? Will it be a "well-behaved Unix daemon process"?

推荐答案

假设你的守护进程有某种持续运行的方式(一些事件循环、扭曲等等)，你可以尝试使用 upstart.

Assuming your daemon has some way of continually running (some event loop, twisted, whatever), you can try to use upstart.

这是一个假设的 Python 服务的示例 upstart 配置:

Here's an example upstart config for a hypothetical Python service:

description "My service"
author  "Some Dude <[e-mail]>"

start on runlevel [234]
stop on runlevel [0156]

chdir /some/dir
exec /some/dir/script.py
respawn

如果你把它保存为 script.conf 到 /etc/init 你就简单地做一次

If you save this as script.conf to /etc/init you simple do a one-time

$ sudo initctl reload-configuration
$ sudo start script

您可以使用 stop script 停止它.上面的 upstart conf 说的是在重启时启动这个服务，如果它死了也重启它.

You can stop it with stop script. What the above upstart conf says is to start this service on reboots and also restart it if it dies.

至于信号处理 - 您的进程应该自然地响应 SIGTERM.默认情况下，除非您专门安装了自己的信号处理程序，否则应处理此问题.

As for signal handling - your process should naturally respond to SIGTERM. By default this should be handled unless you've specifically installed your own signal handler.

这篇关于Python 脚本作为 linux 服务/守护进程的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！