#!/usr/bin/perl -w
#
# Copyright (C) 2012 Dominik Schulz <dominik.schulz@gauner.org>
#
# 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; version 2 dated June,
# 1991.
#
# 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
#
# Script to monitor DJabberd servers.
# Mostly an adaptation of Guillaume Blairon's mogliefsd_activity script.
#
# Usage:
#    ln -s /usr/share/munin/plugins/djabberd_ \
#       /etc/munin/plugins/djabberd_{connections,memory,latency,counters}
#
# Configuration variables:
#
#    host (default: '127.0.0.1')
#    port (default: '5200')
#
# Parameters:
#
#    config    (required)
#    autoconf  (optional - only used by munin-config)
#
#%# family=auto
#%# capabilities=autoconf

use strict;
use warnings;
use IO::Socket;

my $djabberd_host = $ENV{host} || "127.0.0.1";
my $djabberd_port = $ENV{port} || 5200;
my $mode          = undef;
my $mode_name     = undef;

# mapping mode to command from which we get the information
my $mode_ref = {
    'connections' => {
        'cmd'    => 'stats',
        'title'  => 'DJabberd Connections',
        'vlabel' => 'connections',
        'fields' => {
            'connections' => {
                'key'         => 'connections',
                'label'       => 'Connections',
                'description' => 'Number of current connections',
                'draw'        => 'LINE1',
                'type'        => 'GAUGE',
            },
            'users' => {
                'key'         => 'users',
                'label'       => 'Users',
                'description' => 'Number of connected users',
                'draw'        => 'LINE1',
                'type'        => 'GAUGE',
            },
        },
    },
    'memory' => {
        'cmd'    => 'stats',
        'title'  => 'DJabberd Memory Statistics',
        'vlabel' => 'Bytes',
        'fields' => {
            'mem_total' => {
                'key'         => 'mem_total',
                'label'       => '',
                'description' => 'Total memory used by DJabberd',
                'draw'        => 'LINE1',
                'type'        => 'GAUGE',
                'filter'      => \&kb2bytes,
            },
            'mem_connections' => {
                'key'         => 'mem_connections',
                'label'       => '',
                'description' => 'Memory used for handling connections',
                'draw'        => 'LINE1',
                'type'        => 'GAUGE',
                'filter'      => \&kb2bytes,
            },
            'mem_per_connection' => {
                'key'         => 'mem_per_connection',
                'label'       => '',
                'description' => 'Memory used per connection',
                'draw'        => 'LINE1',
                'type'        => 'GAUGE',
                'filter'      => \&kb2bytes,
            },
        }
    },
    'latency' => {
        'cmd'    => 'latency',
        'title'  => 'DJabberd Latency Statistics',
        'vlabel' => 'reqs.',
        'fields' => {
            'dotzerozerozerofive' => {
                'key'         => '-0.0005',
                'label'       => 'lt. 0.0005',
                'description' => 'Requests handled in lt. 0.0005s',
                'draw'        => 'AREA',
                'type'        => 'COUNTER',
            },
            'dotzerozeroone' => {
                'key'         => '-0.001',
                'label'       => 'lt. 0.001',
                'description' => 'Requests handled int lt. 0.001s',
                'draw'        => 'STACK',
                'type'        => 'COUNTER',
            },
            'dotzerozerotwo' => {
                'key'         => '-0.002',
                'label'       => 'lt. 0.002',
                'description' => 'Requests handled int lt. 0.002s',
                'draw'        => 'STACK',
                'type'        => 'COUNTER',
            },
            'dotzerozerofive' => {
                'key'         => '-0.005',
                'label'       => 'lt. 0.005',
                'description' => 'Requests handled int lt. 0.005s',
                'draw'        => 'STACK',
                'type'        => 'COUNTER',
            },
            'dotzeroone' => {
                'key'         => '-0.01',
                'label'       => 'lt. 0.01',
                'description' => 'Requests handled int lt. 0.01s',
                'draw'        => 'STACK',
                'type'        => 'COUNTER',
            },
            'dotzerotwo' => {
                'key'         => '-0.02',
                'label'       => 'lt. 0.02',
                'description' => 'Requests handled int lt. 0.02s',
                'draw'        => 'STACK',
                'type'        => 'COUNTER',
            },
        }
    },
    'counters' => {
        'cmd'    => 'counters',
        'title'  => 'DJabberd Counters',
        'vlabel' => 'msgs.',
        'fields' => {
            'clientin_djabberd_iq'                     => { 'key' => 'ClientIn:DJabberd::IQ',                                  'type' => 'COUNTER', },
            'clientin_djabberd_message'                => { 'key' => 'ClientIn:DJabberd::Message',                             'type' => 'COUNTER', },
            'clientin_djabberd_presence'               => { 'key' => 'ClientIn:DJabberd::Presence',                            'type' => 'COUNTER', },
            'clientin_djabberd_stanza_sasl'            => { 'key' => 'ClientIn:DJabberd::Stanza::SASL',                        'type' => 'COUNTER', },
            'clientin_djabberd_stanza_starttls'        => { 'key' => 'ClientIn:DJabberd::Stanza::StartTLS',                    'type' => 'COUNTER', },
            'iniq_get_info_query'                      => { 'key' => 'InIQ:get-{http://jabber.org/protocol/disco#info}query',  'type' => 'COUNTER', },
            'iniq_get_items_query'                     => { 'key' => 'InIQ:get-{http://jabber.org/protocol/disco#items}query', 'type' => 'COUNTER', },
            'iniq_get_roster_query'                    => { 'key' => 'InIQ:get-{jabber:iq:roster}query',                       'type' => 'COUNTER', },
            'iniq_get_bind'                            => { 'key' => 'InIQ:set-{urn:ietf:params:xml:ns:xmpp-bind}bind',        'type' => 'COUNTER', },
            'iniq_get_session'                         => { 'key' => 'InIQ:set-{urn:ietf:params:xml:ns:xmpp-session}session',  'type' => 'COUNTER', },
            'serverin_djabberd_stanza_dialback_result' => { 'key' => 'ServerIn:DJabberd::Stanza::DialbackResult',              'type' => 'COUNTER', },
            'serverin_djabberd_stanza_dialback_verify' => { 'key' => 'ServerIn:DJabberd::Stanza::DialbackVerify',              'type' => 'COUNTER', },
            'auth_success'                             => { 'key' => 'auth_success',                                           'type' => 'COUNTER', },
            'c2s_message'                              => { 'key' => 'c2s-Message',                                            'type' => 'COUNTER', },
            'c2s_presence'                             => { 'key' => 'c2s-Presence',                                           'type' => 'COUNTER', },
            'connect'                                  => { 'key' => 'connect',                                                'type' => 'COUNTER', },
            'deliver_local'                            => { 'key' => 'deliver_local',                                          'type' => 'COUNTER', },
            'deliver_s2s'                              => { 'key' => 'deliver_s2s',                                            'type' => 'COUNTER', },
            'disconnect'                               => { 'key' => 'disconnect',                                             'type' => 'COUNTER', },
        },
    },
};

if ( $0 =~ m/djabberd_(.*)$/ && $mode_ref->{$1} ) {
    $mode_name = $1;
    $mode      = $mode_ref->{$mode_name};
}
else {
    print STDERR "ERROR: Unknown mode '$mode'. Exiting.\n";
    exit -1;
}

if ( $ARGV[0] && $ARGV[0] eq 'suggest' ) {
    print join( "\n", keys %$mode_ref );

    exit 0;
}
elsif ( $ARGV[0] && $ARGV[0] eq "autoconf" ) {
    my $result_ref = &query_djabberd( $djabberd_host, $djabberd_port, $mode );

    if ($result_ref) {
        print "yes\n";
    }
    else {
        print "no\n";
    }

    exit 0;
}
elsif ( $ARGV[0] and $ARGV[0] eq "config" ) {
    print "graph_title " . $mode->{'title'} . "\n";
    print "graph_vlabel " . $mode->{'vlabel'} . "\n";
    print "graph_args -l 0\n";
    print "graph_category chat\n";
    foreach my $field_name ( keys %{ $mode->{'fields'} } ) {
        my $label = $mode->{'fields'}->{$field_name}->{'label'}       || $field_name;
        my $desc  = $mode->{'fields'}->{$field_name}->{'description'} || $mode->{'fields'}->{$field_name}->{'key'};
        my $draw  = $mode->{'fields'}->{$field_name}->{'draw'}        || 'LINE1';
        my $type  = $mode->{'fields'}->{$field_name}->{'type'}        || 'COUNTER';

        print $field_name. '.label ' . $label . "\n";
        print $field_name. '.description ' . $desc . "\n";
        print $field_name. '.draw ' . $draw . "\n";
        print $field_name. '.type ' . $type . "\n";
    }

    exit 0;
}
else {
    my $result_ref = &query_djabberd( $djabberd_host, $djabberd_port, $mode );

    foreach my $field_name ( keys %{ $mode->{'fields'} } ) {
        my $key = $mode->{'fields'}->{$field_name}->{'key'};
        if ( defined( $result_ref->{$key} ) ) {    # check for definedness, may well be zero (false for perl)
            my $value = $result_ref->{$key};

            # if there is a filter defined for this key apply it now
            if ( exists( $mode->{'fields'}->{$field_name}->{'filter'} ) && ref( $mode->{'fields'}->{$field_name}->{'filter'} ) eq 'CODE' ) {
                $value = &{ $mode->{'fields'}->{$field_name}->{'filter'} }($value);
            }
            print $field_name. ".value " . $value . "\n";
        }
    }
}

sub query_djabberd {
    my ( $host, $port, $mode ) = @_;

    my $conn = IO::Socket::INET::->new(
        PeerAddr => $host,
        PeerPort => $port,
        Proto    => 'tcp',
        Timeout  => 5,
    ) or die($!);

    my $request = $mode->{'cmd'} . "\n";

    $conn->syswrite( $request, length($request) );

    my @lines = ();
    while ( my $line = $conn->getline() ) {
        if ( $line =~ /^\./ ) {
            last;
        }
        push( @lines, $line );
    }
    close($conn);

    my $result_ref = {};
    foreach my $line (@lines) {
        my ( $key, $value, $unit ) = split /\s+/, $line;
        if ( $key && $value ) {
            $result_ref->{$key} = $value;
        }
    }

    return $result_ref;
}

# transform kb => bytes
sub kb2bytes {

    my $num = shift;

    if ( $num && $num =~ m/^\d+$/ ) {
        $num *= 1024;
    }

    return $num;
}