Summarise exim4 email failures

email_failures.py

#!/usr/bin/python

import glob
import gzip
import datetime

logfiles = glob.glob("/var/log/exim4/mainlog*")
time_format = "%Y-%m-%d %H:%M:%S"

def all_lines():
    for filename in logfiles:
        if ".gz" in filename:
            f = gzip.open(filename)
        else:
            f = open(filename)

        for line in f:
            yield line

        f.close()

days = {}

for line in all_lines():
    split = line.split()
    when = " ".join(split[0:2])

    if len(split) > 3 and split[3] == '**':
        day = datetime.datetime.strptime(when, time_format).date()
        if day not in days:
            days[day] = {}
        failures = days[day]

        local_part, domain = split[4].split("@")
        if domain not in failures:
            failures[domain] = 0

        failures[domain] += 1

print "Outgoing email hard failure summary"
print

for day, failures in sorted(days.items()):
    print day
    for domain, times in sorted(failures.items(), key=lambda (d, t): -t):
        print "  ", str(times).rjust(5), domain