python监控tomcat日志，内存溢出错误

#!/usr/bin/python 
#-*- coding:utf-8 -*-
#
import os
from os.path import getsize
from sys import exit
from re import compile, IGNORECASE
import sys, getpass
import smtplib
from email.mime.text import MIMEText

tomcat_log = '/data/server/tomcats/'
# 匹配的错误信息关键字的正则表达式
pattern = compile('outofmemoryerror', IGNORECASE)

#定义发送邮件函数
def mail(content):
  email_host = 'smmprd@smm-app02.wisers.com'
  maillist ='wanglisheng@wisers.com,yangxuejun@wisers.com,taosijun@wisers.com,tanxin@wisers.com,kyleli@wisers.com'
  #maillist='tanxin@wisers.com'
  me = email_host

  msg = MIMEText(content)
  msg['Subject'] = 'tomcat OutOfMemory Appear'
  msg['From'] = me
  msg['To'] = maillist

  try:
    smtp = smtplib.SMTP('localhost')
    smtp.sendmail(me, maillist.split(','), msg.as_string())
    smtp.quit()
    print ('email send success.')
  except smtplib.SMTPException:
    print "Error: 无法发送邮件"
#读取上一次日志文件的读取位置
def get_last_position(file):
  try:
    data = open(file, 'r')
    last_position = data.readline()
    if last_position:
      last_position = int(last_position)
    else:
      last_position = 0
  except:
      last_position = 0
  return last_position

#写入本次日志文件的读取到的本次位置
def write_this_position(file, last_position):
  try:
    data = open(file, 'w')
    data.write(str(last_position))
    data.write('\n' + "Don't Delete This File,It is Very important for Looking Tomcat Error Log !! \n")
    data.close()
  except:
    print "Can't Create File !" + file
    exit()

#分析文件找出Outofmemory
def analysis_log(file):
  #error_list = []
  #try:
  #  data = open(file, 'r')
  #except:
  #  exit()
  for logname in os.listdir(file):  #循环多个tomcat的路径
    L = os.path.join(tomcat_log, logname)
    if os.path.isdir(L):
      last_position_logfile = ''.join([L,'/error_last_position.txt']) #拼接记录读取位置路径
      last_position = get_last_position(last_position_logfile)
      dir_log = ''.join([L,'/logs','/catalina.out'])
      if os.path.exists(dir_log):
        #print (dir_log)
        this_position = getsize(dir_log)
        try:
          data = open(dir_log, 'r')
        except:
          continue
        if this_position < last_position: #log文件小于上次读取的大小，从log文件开始位置读取（日志重新生成了的情况）
          data.seek(0)
        elif this_position == last_position: #log文件大小=上次读取大小， （日志没变化） 
          exit()
        elif this_position > last_position:  #log 文件大于上次读取的大小，从上次大小位置增量读取
          data.seek(last_position) #移动文件读取指针到指定位置
        error_list = []
        for line in data:
          if pattern.search(line):
            error_list.append(line)
        write_this_position(last_position_logfile, data.tell()) #data.tell()返回文件指针的当前位置, 将位置写入保存文件中
        data.close()
        #print(error_list)
        if len(error_list) != 0:
          error_info = str(error_list)
          mail(''.join([logname,': ', error_info]))   # 调用发送邮件函数发送邮件
      #return ''.join(error_list)
analysis_log(tomcat_log)