A very simple Apache access log parser in Python

python_apache_logs.py

#!/usr/bin/env python3

import json
import re
import sys

parts = [
    r'(?P<host>\S+)',                   # host %h
    r'\S+',                             # indent %l (unused)
    r'(?P<user>\S+)',                   # user %u
    r'\[(?P<time>.+)\]',                # time %t
    r'"(?P<request>.*)"',               # request "%r"
    r'(?P<status>[0-9]+)',              # status %>s
    r'(?P<size>\S+)',                   # size %b (careful, can be '-')
    r'"(?P<referrer>.*)"',              # referrer "%{Referer}i"
    r'"(?P<agent>.*)"',                 # user agent "%{User-agent}i"
]
pattern = re.compile(r'\s+'.join(parts)+r'\s*\Z')

with open(sys.argv[1], "r") as log_file:
  for line in log_file:
    print(json.dumps(pattern.match(line).groupdict()))