#!/bin/bash
#
# Copyright (C) 2006-2009 Benjamin Schweizer. All rights reserved.
#
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#
#
# Abstract
# ~~~~~~~~
# This is a plugin for the munin monitoring system. It graphs the cache
# efficiency of your squid proxy servers and shows nice graphs for average
# byte and request hits.
#
# Authors
# ~~~~~~~
# Benjamin Schweizer, http://benjamin-schweizer.de/contact
#
# Changes
# ~~~~~~~
# 2009-11-25, volker: added config options and docs
# 2009-11-19, benjamin: fixed squid3 compatibility, minor rewrite
# 2006-11-16, benjamin: removed 5 minutes stats, fixed 5% bug
# 2006-10-26, benjamin: excluded negative values from result
# 2006-10-11, benjamin: initial release.
#
# Todo
# ~~~~
# - we'll see
#
# Munin:
#%# family=auto
#%# capabilities=autoconf
#
# Config
# ~~~~~~
# This plugin supports munin-autoconf, but you might need to change the host
# and port according to your actual setup. You can overwrite the defaults
# in your node config (/etc/munin/plugin-conf.d/) like this:
#
#	[squid_efficiency]
#	env.squidhost yourhost.example.com
#	env.squidport 8080 
#

host=${squidhost:-localhost}
port=${squidport:-3128}

test "$1" = "autoconf" && {
    which netcat > /dev/null || {
        echo "netcat binary not found"
        exit 1
    }
	DUMP=`printf "GET cache_object://$host/info HTTP/1.0\n\n" | netcat $host $port`
    test -n "$DUMP"  || {
        echo "http response empty"
        exit 1
    }
    echo "yes"
    exit 0
}

test "$1" = "config" && {
	echo 'graph_title Squid Efficiency'
	echo 'graph_info This graph shows the proxy efficiency.'
	echo 'graph_category squid'
	echo "graph_args --lower-limit 0 --upper-limit 100"
	echo 'graph_vlabel %'
	echo 'request.label request hits'
	echo 'byte.label byte hits'
	exit 0
}

DUMP=`printf "GET cache_object://$host/info HTTP/1.0\n\n" | netcat $host $port`
# squid2
#        Request Hit Ratios:     5min: 0.0%, 60min: 17.4%
#        Byte Hit Ratios:        5min: 75.0%, 60min: 12.0%
# squid3
#        Hits as % of all requests:    5min: 0.0%, 60min: 0.0%
#        Hits as % of bytes sent:    5min: 100.0%, 60min: 100.0%
test -n "$DUMP"  || {
    echo "http response empty"
    exit 1
}

REQUEST_HITS=`echo "$DUMP" | grep -E "Request Hit Ratios|Hits as % of all requests" | cut -d ":" -f4 | cut -d "." -f1 | xargs echo`
test $REQUEST_HITS -gt 0 || REQUEST_HITS=0
BYTE_HITS=`echo "$DUMP" | grep -E "Byte Hit Ratios|Hits as % of bytes sent" | cut -d ":" -f4 | cut -d "." -f1 | xargs echo`
test $BYTE_HITS -gt 0 || BYTE_HITS=0

echo "request.value ${REQUEST_HITS}"
echo "byte.value ${BYTE_HITS}"

# eof.