#!/usr/bin/perl -w
#
# byprojects_inout_bandwidth
#
# Perl script to monitor in/out bandwidth *byprojects* (e.g. vhost) from multiple files and/or regex.
#
# Danny Fullerton <northox@mantor.org> 
# Mantor Organization <www.mantor.org>
#
# You need logtail (https://www.fourmilab.ch/webtools/logtail/) and 
#
# Apache:
# mod_logio apache module (https://httpd.apache.org/docs/2.0/mod/mod_logio.html).
# Your logformat should look like this "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\" %I %O"
# where %I is input and %O is output.
#
# Log can be gather from multiple sources by simply specifying multiple log filename and/or an array with two
# elements: log filename and a regex.
#   - 'prod' => array('/home/prod/log/access.log'),
#     Prod graph will be using everything in /home/prod/log/access.log
#   - 'test' => array(array('/var/log/httpd/access.log', '"[A-Z]+ /test/'), '/home/test/log/access.log')
#     Test graph will be using eveything in /home/test/log/access.log and stuff that match '"[A-Z] /test/' in 
#     /var/log/httpd/access.log such as '"GET /test/'

$server = 'Apache';

$statepath = '/usr/local/var/munin/plugin-state'; # directory where logtail will save the state
$logtail = '/usr/local/bin/logtail';

%logs = (
'prod' => ('/home/prod/log/access.log'),
'test' => (
            ('/var/log/httpd/access.log', '"[A-Z]+ /test/'),
            '/home/test/log/access.log'
          )
);

###########

if(defined($ARGV[0])) {
  if ($ARGV[0] eq 'autoconf') {
    print "yes\n";
    exit(0);
  } elsif ($ARGV[0] eq 'config') {
    print "graph_title $server in/out bandwidth byprojects\n";
    print "graph_args --base 1000\n";
    print "graph_vlabel bits per \${graph_period} in (-) / out (+)\n";
    print "graph_category $server\n";
    print "graph_info This graph show $server in/out bandwidth used by various projects.\n";
    while (($client, $files) = each(%logs)) {
      print "i".$client.".label $client\n";
      print "i".$client.".type GAUGE\n";
      print "i".$client.".graph no\n";
      print "i".$client.".cdef i".$client.",8,*\n";
      print "o".$client.".label $client\n";
      print "o".$client.".type GAUGE\n";
      print "o".$client.".negative i".$client."\n";
      print "o".$client.".cdef o".$client.",8,*\n";
    }
    exit(0);
  }
}

while (($client, $files) = each(%logs)) {
  $i = $o = $x = 0;
  foreach $file ($files) {
    $regex = '';
    $state = $statepath.'/'.$client.$x.'_inoutbandwidth.state';
    if(ref($file) eq 'ARRAY') { ($file, $regex) = @file }
    open(my $lt, "$logtail -f $file -o $state |") or die "Can't open $logtail : $!";
    while (<$lt>) {
      $buf = $_;
      if($buf eq '') { next }
      if(!defined($regex) || $buf =~ m/$regex/) {
        if($buf =~ m/(\d+) (\d+)$/) {
          $i += $1;
          $o += $2;
        }
      }
    }
    close($lt);
    $x++;
  }
  print "i".$client.".value $i\n";
  print "o".$client.".value $o\n";
}
