Merging and sorting log files in Python

Question

I am completely new to python and I have a serious problem which I cannot solve.

I have a few log files with identical structure:

[timestamp] [level] [source] message

For example:

[Wed Oct 11 14:32:52 2000] [error] [client 127.0.0.1] error message

I need to write a program in pure Python which should merge these log files into one file and then sort the merged file by timestamp. After this operation I wish to print this result (the contents of the merged file) to STDOUT (console).

I don't understand how to do this would like help. Is this possible?

Answer 1

You can do this

import fileinput
import re
from time import strptime

f_names = ['1.log', '2.log'] # names of log files
lines = list(fileinput.input(f_names))
t_fmt = '%a %b %d %H:%M:%S %Y' # format of time stamps
t_pat = re.compile(r'\[(.+?)\]') # pattern to extract timestamp
for l in sorted(lines, key=lambda l: strptime(t_pat.search(l).group(1), t_fmt)):
    print l,