An example of python dynamically monitoring log content

Log files are generally generated on a daily basis, then by determining the date and current time of file generation in the program, replace the monitored log files
The program is just a simple example of monitoring test1.log for 10 seconds and then moving on to monitoring test2.log

Program monitoring USES the Linux command tail-f to dynamically monitor newly appended logs

#!/usr/bin/python
# encoding=utf-8
# Filename: monitorLog.py
import os
import signal
import subprocess
import time

logFile1 = "test1.log"
logFile2 = 'test2.log'
# Log files are generally generated on a daily basis, then by determining the date and current time of file generation in the program, replace the monitored log files 
# The program is just a simple example of monitoring test1.log 10 Seconds, turn to monitor test2.log
def monitorLog(logFile):
    print ' Monitored log files   is %s' % logFile
    #  The program runs 10 Second, monitor another log 
    stoptime = time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(time.time() + 10))
    popen = subprocess.Popen('tail -f ' + logFile, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)
    pid = popen.pid
    print('Popen.pid:' + str(pid))
    while True:
        line = popen.stdout.readline().strip()
        #  Determine if the content is empty 
        if line:
            print(line)
        #  The current time 
        thistime = time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(time.time()))
        if thistime >= stoptime:
            #  Terminate child process 
            popen.kill()
            print ' kill subprocess'
            break
    time.sleep(2)
    monitorLog(logFile2)
if __name__ == '__main__':
    monitorLog(logFile1)