使用python编写脚本以验证apache状态

Question

我需要做一个脚本来检查apache2是否工作，如果是，它会给出一个确认消息，如果不是，它会启动apache2，问题是我的脚本在apache需要启动时有一个错误，但是它在apache2已经启动时工作

这是一个linux服务器，只是为了启动apache，但我在这方面是新手

    services = ['apache2']
    for service in services:
            status = subprocess.check_output("/etc/init.d/"+service+" status", shell=True)
            if ("is stopped" in status):
                    print service + "  - Stopped"
                    print service + "  - Trying to start"
                    service_start = subprocess.check_output("/etc/init.d/"+service+" start", shell=True)
            else:
                    print service + "  - Running "

错误消息是：

status = subprocess.check_output("/etc/init.d/"+service+" status", shell=True)
File "/usr/lib/python2.7/subprocess.py", line 223, in check_output
raise CalledProcessError(retcode, cmd, output=output)
subprocess.CalledProcessError: Command '/etc/init.d/apache2 status' returned non-zero exit status 3

Answer 1

check_output引发异常当进程返回值不是0时，需要用try except语句包装调用

import subprocess

services = ['apache2']
for service in services:
    try:
        status = subprocess.check_output("/etc/init.d/"+service+" status", shell=True)
    except subprocess.CalledProcessError as e:
        status = "is stopped"

        if ("is stopped" in status):
                print service + "  - Stopped"
                print service + "  - Trying to start"
                service_start = subprocess.check_output("/etc/init.d/"+service+" start", shell=True)
        else:
                print service + "  - Running "