#!/bin/sh
: << =cut

=head1 NAME

radsniff - A plugin to consume statistics generated by radsniff via collectd RRD files

=head1 APPLICABLE SYSTEMS

radsniff 3.1.x or later

=head1 CONFIGURATION

This plugin uses the following configuration variables:

 [radsniff]
  env.host       - The host collectd thinks the radsniff data
                   originated from (defaults to current host).
  env.rrd_path   - Path to the directory containing rrd files.
  env.type       - Either radius_rtx, radius_latency or radius_count
  env.pkt_type   - The type of packet to graph.
  env.instance   - radsniff instance name (passed to radsniff with -N).

=head1 AUTHOR

Copyright (C) 2014 Arran Cudbard-Bell <a.cudbardb@freeradius.org>

=head1 LICENSE

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA

=head1 MAGIC MARKERS

 #%# family=manual

=cut

if [ -z "$type" ]; then
    echo "env.type must be set" >&2
    exit -1
fi

if [ -z "$pkt_type" ]; then
    echo "env.pkt_type must be set" >&2
    exit -1
fi

if [ "$1" = "config" ]; then
    pretty_pkt_type=`echo "$pkt_type" | sed -e 's/_/ /g' | sed 's/^./\U&\E/'`

    case "$type" in
        radius_rtx)
            echo "graph_title ${pretty_pkt_type} rtx"
            echo 'graph_args --base 1000 -l 0 '
            echo 'graph_period second'
            echo 'graph_vlabel Exchanged / ${graph_period}'
            echo 'graph_category RADIUS'

            echo 'none.label no loss'
            echo 'none.info Responses received after first request'
            echo 'none.type GAUGE'
            echo 'none.min 0'

            echo 'one.label 1'
            echo 'one.info Responses received after one retransmission'
            echo 'one.type GAUGE'
            echo 'one.min 0'

            echo 'two.label 2'
            echo 'two.info Responses received after two retransmissions'
            echo 'two.type GAUGE'
            echo 'two.min 0'

            echo 'three.label 3'
            echo 'three.info Responses received after three retransmissions'
            echo 'three.type GAUGE'
            echo 'three.min 0'

            echo 'four.label 4'
            echo 'four.info Responses received after four retransmissions'
            echo 'four.type GAUGE'
            echo 'four.min 0'

            echo 'more.label more'
            echo 'more.info Responses received after more than four retransmissions'
            echo 'more.type GAUGE'
            echo 'more.min 0'

            echo 'lost.label lost'
            echo 'lost.info Requests to which no response was seen'
            echo 'lost.type GAUGE'
            echo 'lost.min 0'
            ;;

        radius_latency)
            echo "graph_title ${pretty_pkt_type} latency"
            echo 'graph_args --base 1000 -l 0 '
            echo 'graph_vlabel Latency (ms)'
            echo 'graph_category RADIUS'

            echo 'smoothed.label smoothed avg'
            echo 'smoothed.info Smoothed average'
            echo 'smoothed.type GAUGE'
            echo 'smoothed.min 0'

            echo 'avg.label avg'
            echo 'avg.info Average latency over the stats interval'
            echo 'avg.type GAUGE'
            echo 'avg.min 0'

            echo 'high.label high'
            echo 'high.info Highest latency over the stats interval'
            echo 'high.type GAUGE'
            echo 'high.min 0'

            echo 'low.label low'
            echo 'low.info Lowest latency over the stats interval'
            echo 'low.type GAUGE'
            echo 'low.min 0'
            ;;

        radius_count)
            echo "graph_title $pretty_pkt_type counters"
            echo 'graph_args --base 1000 -l 0 '
            echo 'graph_period second'
            echo 'graph_vlabel Packets / ${graph_period}'
            echo 'graph_category RADIUS'

            echo 'received.label received'
            echo 'received.info Packets of this type received'
            echo 'received.type GAUGE'
            echo 'received.min 0'

            echo 'linked.label linked'
            echo 'linked.info Packets linked to another request or response'
            echo 'linked.type GAUGE'
            echo 'linked.min 0'

            echo 'unlinked.label unlinked'
            echo 'unlinked.info Packets not linked to another request or response'
            echo 'unlinked.type GAUGE'
            echo 'unlinked.min 0'

            echo 'reused.label reused'
            echo 'reused.info Request which (prematurely) re-used the same ID as a previous request'
            echo 'reused.type GAUGE'
            echo 'reused.min 0'
            ;;
        *)
            echo "env.type ($type) is invalid must be radius_rtx, radius_latency, or radius_count" >&2
            exit -1
    esac
    exit 0
fi

HOST=${host:-`hostname -f`}
INSTANCE=${instance:-'radsniff'}
RRD_PATH=${rrd_path:-"/var/lib/collectd/rrd/${HOST}/${INSTANCE}-exchanged"}
RRD_PATH="${RRD_PATH}/${type}-${pkt_type}.rrd"
RRD_RES=${rrd_res:-300}

if [ ! -e "$RRD_PATH" ]; then
    echo "rrd file '$RRD_PATH' does not exist" >&2
    exit -1
fi

fetch_data()
{
    # RRD tool doesn't always select the correct period (seems
    # to round up and give us -nan results) in the interest of
    # gap free graphing, we attempt to get the last two periods
    # worth of data, and then use the newest non -nan one.
    # It's not perfect and should be fixed at some point...
    rrd_last=`rrdtool fetch "$RRD_PATH" $1 -r $RRD_RES -e $(expr $(date +%s) / $RRD_RES \* $RRD_RES) -s end-$(expr $RRD_RES \* 2)`; ret=$?
    if [ $ret -ne 0 ]; then
        echo "$rrd_last" >&2
        exit $ret
    fi
    echo "$rrd_last" | head -1
    echo "$rrd_last" | grep '^[0-9]*:' | grep -v -E '^[0-9]*:( -nan)*$' | tail -1
}

fetch_data_column()
{
    echo "$(fetch_data $1)" | tail -1 | cut -d ' ' -f $(expr $2 + 2)
}

case "$type" in
    radius_rtx)
        col=2
        rrd_data=$(fetch_data 'AVERAGE')
        for var in `echo "$rrd_data" | head -1`; do
            case "$var" in
                1) printf "one.value ";;
                2) printf "two.value ";;
                3) printf "three.value ";;
                4) printf "four.value ";;
                *) printf "$var.value ";;
            esac
            echo "$rrd_data" | tail -1 | cut -d ' ' -f $col
            col=`expr $col + 1`
        done
        ;;

    radius_count)
        col=2
        rrd_data=$(fetch_data 'AVERAGE')
        for var in `echo "$rrd_data" | head -1`; do
            printf "$var.value "
            echo "$rrd_data" | tail -1 | cut -d ' ' -f $col
            col=`expr $col + 1`
        done
        ;;

    radius_latency)
        printf "smoothed.value "
        fetch_data_column 'AVERAGE' 0

        printf "avg.value "
        fetch_data_column 'AVERAGE' 1

        # Averages here are unacceptable because we use this to detect
        # abnormally long delays in responses, and if we average all the highs
        # over a five minute period, transient spikes in latency may be lost.
        printf "high.value "
        fetch_data_column 'MAX' 2

        # Again we need the lowest value of the set here, as an abnormally
        # quick response may indicate something is wrong.
        printf "low.value "
        fetch_data_column 'MIN' 3
        ;;
esac
exit 0