Question

我想编写一个Python脚本，它将每分钟检查Linux机器上是否仍在运行某些预定义的进程，以及该进程在崩溃的时间是否未打印时间戳。我编写了一个脚本，该脚本正是这样做的，但是不幸的是，它仅通过一个进程即可正常工作。

这是我的代码：

import subprocess
import shlex
import time
from datetime import datetime

proc_def = "top"
grep_cmd = "pgrep -a " + proc_def
try:
    proc_run = subprocess.check_output(shlex.split(grep_cmd)).decode('utf-8')
    proc_run = proc_run.strip().split('\n')
    '''
    Creating a dictionary with key the PID of the process and value
    the command line
    '''
    proc_dict = dict(zip([i.split(' ', 1)[0] for i in proc_run],
                         [i.split(' ', 1)[1] for i in proc_run]))

    check_run = "ps -o pid= -p "

    for key, value in proc_dict.items():
        check_run_cmd = check_run + key
        try:
            # While the output of check_run_cmd isn't empty line do
            while subprocess.check_output(
                                          shlex.split(check_run_cmd)
                                          ).decode('utf-8').strip():
                # This print statement is for debugging purposes only
                print("Running")
                time.sleep(3)
        '''
        If the check_run_cmd is returning an error, it shows us the time
        and date of the crash as well as the PID and the command line
        '''
        except subprocess.CalledProcessError as e:
            print(f"PID: {key} of command: \"{value}\" stopped
                  at {datetime.now().strftime('%d-%m-%Y %T')}")
            exit(1)
# Check if the proc_def is actually running on the machine
except subprocess.CalledProcessError as e:
    print(f"The \"{proc_def}\" command isn't running on this machine")

例如，如果有两个top进程，它将仅向我显示有关这些进程之一的崩溃时间的信息，并且它将退出。只要有另一个进程在运行，我就想保持活动状态，并且仅在两个进程都被杀死时才退出。当每个进程崩溃时，它应该提供信息。

它也不应仅限于两个proc，并支持使用同一proc_def命令启动的多个进程。

Answer 1

必须稍微改变一下逻辑，但基本上，您需要一个无限循环来交替检查所有进程-而不是一遍又一遍地检查同一进程：

import subprocess
import shlex
import time
from datetime import datetime

proc_def = "top"
grep_cmd = "pgrep -a " + proc_def
try:
    proc_run = subprocess.check_output(shlex.split(grep_cmd)).decode('utf-8')
    proc_run = proc_run.strip().split('\n')
    '''
    Creating a dictionary with key the PID of the process and value
    the command line
    '''
    proc_dict = dict(zip([i.split(' ', 1)[0] for i in proc_run],
                         [i.split(' ', 1)[1] for i in proc_run]))

    check_run = "ps -o pid= -p "
    while proc_dict:
        for key, value in proc_dict.items():
            check_run_cmd = check_run + key
            try:
                # While the output of check_run_cmd isn't empty line do
                subprocess.check_output(shlex.split(check_run_cmd)).decode('utf-8').strip()
                # This print statement is for debugging purposes only
                print("Running")
                time.sleep(3)
            except subprocess.CalledProcessError as e:
                print(f"PID: {key} of command: \"{value}\" stopped at {datetime.now().strftime('%d-%m-%Y %T')}")
                del proc_dict[key]
                break
# Check if the proc_def is actually running on the machine
except subprocess.CalledProcessError as e:
    print(f"The \"{proc_def}\" command isn't running on this machine")

这在原始代码中也遇到了同样的问题，即时间分辨率为3秒，并且如果在此脚本中运行了新进程，则不会对其进行ping操作（尽管这可能是理想的）。

第一个问题可以通过根据需要减少睡眠时间来解决，第二个问题可以通过运行在proc_dict中创建while True的初始行来解决。

Python脚本检查特定的Linux命令是否仍在运行

1 个答案: