统计nginx日志里每五分钟的访问量

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author:Random_lee
import time
import os
import re

def count_pv():
    logfile = 'access_log'
    if not os.path.exists(logfile):
        print('error:' + logfile + ' not existed.')
        return 0

    else:
        f=open(logfile,'r')
        num=0
        for line in f:
            expr= re.compile('^(?P<RemoteIP>.*) - - (?P<datatime>.*) (?P<request>".+") (?P<status>\d{3}) (?P<web_size>\d{1,10})')
            try:
                log_info=expr.search(line)
                log_info=log_info.groupdict()

                # 解析日志信息
                datatime = log_info["datatime"]
                # 取出日志信息中的datatime
                datatime = datatime.replace('[', '')
                datatime = datatime.replace(']', '')
                # 去掉[]
                data_time = datatime.split(' ')[0]
                # 取出日期时间
                time_zone = datatime.split(' ')[1]
                # 取出时区
                if time_zone == '+0800':
                    # print(time_zone)
                    # print(data_time)
                    ctime = time.strptime(data_time, '%d/%b/%Y:%H:%M:%S')
                    # 转换为格式化时间
                    time_stamp = time.mktime(ctime)
                    # 转换为时间戳
                    # print(time_stamp)
                    if time.time() - time_stamp <= 300:
                        num+=1
                        # print(datatime)
                    else:
                        # print("error data_time:%s"%datatime)
                        pass
                else:
                    return 0
            except:
                pass
        f.close()
        return num

a=count_pv()
a=str(a)
status_file=open('pv_info','w')
status_file.write(a)