Ability to configure Apache access_log field number

plugins/apache/apache_average_time_last_n_requests

@@ -1,5 +1,4 @@
 #!/usr/bin/perl -w
-# $Id$
 # Author: Nicolas Mendoza <[email protected]> - 2008-06-18
 #
 # Monitors the average time requests matching a custom regexp takes
@@ -16,12 +15,16 @@
 # For instance: 
 #   LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-agent}i\" %T %v"
 # Check http://httpd.apache.org/docs/2.2/mod/mod_log_config.html#formats for more info
+#
+# Configurable variables
+# 	fieldno      - Override the default field number
+#%# family=auto
 
 use strict;
 
 my $LAST_N_REQUESTS = 100000; # calculate based on this amount of requests
 my $ACCESS_LOG_PATTERN = '/var/log/apache2/access.log.*'; # log pattern, if many it will take the last one.
-my $TIME_FIELD_INDEX = -2; # second last field
+my $TIME_FIELD_INDEX =  exists $ENV{'fieldno'} ? $ENV{'fieldno'} : -2; # second last field
 
 my $config =<< "CONFIG"
 graph_title Apache average seconds last $LAST_N_REQUESTS requests