Postfix statistical graphs using passive checks for PRTG

We are using PRTG to monitor our system and decided to add a new sensor for our Postfix mail server. After a bit of searching, I found this nice howto for Zabbix and I did a small modification on the scrip to generate as output a XML for SSH Script Advanced sensor. Only thing you have to run this script is pflogsumm and logtail.

#!/usr/bin/env bash

MAILLOG=/var/log/mail.log
PFOFFSETFILE=/tmp/postfix-offset.dat
PFSTATSFILE=/tmp/postfix_statsfile.dat
TEMPFILE=$(mktemp)
TODAY=$(date +'%b %d')
PFLOGSUMM=/home/telni/pflogsumm/pflogsumm.pl
LOGTAIL=/home/telni/logtail/logtail

PFVALS=( 'received' 'delivered' 'forwarded' 'deferred' 'bounced' 'rejected' 'held' 'discarded' 'reject_warnings' 'bytes_received' 'bytes_delivered' )

[ ! -e "${PFSTATSFILE}" ] && touch "${PFSTATSFILE}" && chown telni:telni "${PFSTATSFILE}"

printvalues() {
 key=$1
 pfkey=$(echo "$1" | tr '_' ' ')
 value=$(grep -m 1 "${pfkey}" $TEMPFILE | awk '{print $1}' | awk '/k|m/{p = /k/?1:2}{printf "%d\n", int($1) * 1024 ^ p}')
 old_value=$(grep -e "^${key};" "${PFSTATSFILE}" | cut -d ";" -f2)
 if [ -n "${old_value}" ]; then
 sed -i -e "s/^${key};${old_value}/${key};$((${old_value}+${value}))/" "${PFSTATSFILE}"
 if [[ ${key} =~ bytes.* ]]; then
 echo -e " <result>\n <channel>${key}</channel>\n <value>$((${value}/1024))</value>\n </result>"
 else
 echo -e " <result>\n <channel>${key}</channel>\n <value>${value}</value>\n </result>"
 fi
 else
 echo "${key};${value}" >> "${PFSTATSFILE}"
 echo -e " <result>\n <channel>${key}</channel>\n <value>0</value>\n </result>"
 fi
}

echo "<prtg>"

"${LOGTAIL}" -f"${MAILLOG}" -o"${PFOFFSETFILE}"| "${PFLOGSUMM}" -h 0 -u 0 --bounce_detail=0 --deferral_detail=0 --reject_detail=0 --no_no_msg_size --smtpd_warning_detail=0 > "${TEMPFILE}"
for i in "${PFVALS[@]}"; do
 printvalues "$i"
done

echo "</prtg>"

rm "${TEMPFILE}"