t3_mail.pl

#!/usr/bin/perl 
#
# Script to parse mail.log from postfix
# and send information to a .csv file.
# Information is sender, recipient, date,
# size and status of message.
#
# Author: Anton Lindström
# me@antonlindstrom.com
#
use strict;
use warnings;

my $maillog = "/var/log/mail.log";
my $csvfile = "logmail.csv";

# Open maillog.
open(LOG, $maillog);
my @mailentries = <LOG>;
close(LOG);

# Define some global variables.
my (%from, %size, %to, %status, $postscsv);

foreach (@mailentries) {
  # Next if the row does not contain a mailadress.
  next if ($_ !~ /[\w\-\_\.]+\@[\w\-\_\.]+\.[a-z]+/);

  # Collect data from log.
  $_ =~ m/(\w+\s\d+\s\d+\:\d+\:\d+)\s.+\[[0-9]+\]\:\s([\w]+)\:(\s(from\=\<(.+)\>\,\ssize\=([0-9]+),)|(\sto\=\<([\w\-\_\.]+\@[\w\-\_\.]+\.[a-z]+)\>.+status\=(.+\))))/gi;

  # Assign variables, $mailid is identifier for mail, therefor it can be used as key in hash.
  # All posts are assigned to a hash with the $mailid as key.
  my ($date, $rid)  = ($1, $2); 
  ($from{$rid}, $size{$rid})    = ($5, $6) if ($5 && $6);
  ($to{$rid}, $status{$rid})    = ($8, $9) if ($8 && $9);
  
  # Formated csv-string, this is global!
  $postscsv .= "$from{$rid},$to{$rid},$date,$size{$rid},$status{$rid}\n" 
  if ( $date && $rid && exists($from{$rid}) && exists($size{$rid}) && exists($to{$rid}) && exists($status{$rid}) );
}

# Write to $csvfile. 
open(CSV, "> $csvfile");
print CSV $postscsv;
close(CSV);