python tailf demo

python tailf demo

#!/usr/bin/env python

import re


class Tail:

    def __init__(self, file=None, regex=None):
        self.__file = file
        self.__mode = 'r'
        self.__regex = regex

    def tail(self):
        with open(self.__file, self.__mode) as fd:
            fd.seek(0, 2)
            while True:
                cur = fd.tell()
                line = fd.readline()
                if line:
                    rst = self.regex(line)
                    if rst:
                        yield rst

    def regex(self, data):
        print(self.__regex)
        r = re.compile(self.__regex)
        rst = re.match(r, data)
        if rst:
            return rst.group()


if __name__ == "__main__":
    tail_obj = Tail(file='./access.log', regex='I Love Python.')
    for i in tail_obj.tail():
        print(i)