Scrape pf QOS metrics for forwarding to InfluxDB

get_pfqueue_data.sh

#!/bin/sh
#
# Shell script: get_pfqueue_data.sh
# Date: 21-Dec-2016
#
# Script to scrape queue metrics from pfctl
# and output in influxdb line protocol with interface name &
# q name as tags and q bytes & q drops as data.
#
# Copy this script to a directory on your pfsense machine and ensure
# it is executable.  It requires the privileges of a user with permission
# to read /dev/pf.
#
# This script should be invoked with the target influxdb measurement name
# as the single argument (e.g. 'get_pfqueue_data.sh pf_metrics' where 
# pf_metrics is the measurement name)and is meant to be used in 
# combination with telegraf inputs.exec plugin to forward stats to 
# the influx server. The influxdb database name and retention policy 
# are configured within telegraf.
#
# Suggest using telegraf output filtering to only forward data for queues 
# for which metrics are wanted.

if test X"$1" = 'X'
then
  echo "Error!  No measurement name provided"
  exit
fi
  
pfctl_output=$(pfctl -s queue -v)
dt=$(date +%s)
dt=$(($dt*1000000000))

qdrops() {
drops=$(echo $pfctl_output | grep -o -E 'dropped pkts: *[0-9]*' | sed -n -e 's/^.*pkts:[ \t]* //p' | sed -n "$4"p)
bytes=$(echo $pfctl_output | grep -o -E '\[ pkts: *[0-9]* *bytes: *[0-9]*' | sed -n -e 's/^.*bytes:[ \t]* //p' | sed -n "$4"p)
qdepth=$(echo $pfctl_output | grep -o -E '\[ qlength: *[0-9]*' | sed -n -e 's/^.*qlength:[ \t]* //p' | sed -n "$4"p) 
echo $1',interface='$2',queue='$3' drops='$drops'i,bytes='$bytes'i,qdepth='$qdepth'i '$dt
}

index=1
for q in $(echo $pfctl_output | grep -o -E '[A-Za-z0-9_]* on' | cut -d ' ' -f1)
do
 r=$(echo $q | grep -o -E 'root')
 if test X"$r" = 'Xroot'
 then
    iface=$(echo $q | cut -d"_" -f2)
    index=$(($index+1))
 else
    qdrops $1 $iface $q $index
    index=$(($index+1))
 fi
done