#!/bin/bash

: << =cut

=head1 NAME

Munin plugin to monitor apache mod_cache_disk usage.

=head1 CONFIGURATION

 [apache_cache_disk_count]
 user www-data
 env.cache_path /var/cache/apache2/mod_cache_disk
 env.strings css js
 env.label_cs CSS
 env.colour_css FFFF00
 env.label_js JS
 env.colour_js FF0000

=head1 AUTHOR

Raphaël Droz <raphael.droz+floss@gmail.com>

=head1 LICENSE

GPLv2

=head1 MAGICK MARKERS

 #%# family=auto
 #%# capabilities=autoconf

=cut

. $MUNIN_LIBDIR/plugins/plugin.sh

my_cache_path="${cache_path:-/var/cache/apache2/mod_cache_disk}"
declare -a fieldnames labels colours

getenvdata() {
    let during_autoconf=0
    [[ $1 == -v ]] && during_autoconf=1
    arg=( "${strings:-}" )
    for i in ${arg[*]}; do
        if [[ ! $i =~ ^[a-zA-Z0-9]+$ ]]; then
            (( $during_autoconf )) && echo "no ($i isn't a valid fixed-string)"
            ok=0
            continue
        fi
        label=label_$i
        if [[ -z "${!label}" ]]; then
            (( $during_autoconf )) && echo "no ($i isn't given a label)"
            ok=0
            continue
        fi
        colour=colour_$i
        if [[ -z "${!colour}" ]]; then
            (( $during_autoconf )) && echo "no ($i isn't given a colour)"
            ok=0
            continue
        fi

        fieldnames+=($i)
        labels+=("${!label}")
        colours+=("${!colour}")
    done
}

if [[ $1 == autoconf ]]; then
    let ok=1

    [[ -z $strings ]] && echo "no strings to monitor defined" && ok=0
    ! type -P htcacheclean &>/dev/null && echo "can't find htcacheclean" && ok=0
    ! test -d "$my_cache_path" && echo "cache_path \"$cache_path\" is not readable" && ok=0

    getenvdata -v

    (( ${#fieldnames[*]} == 0 )) && echo "no (no valid strings)" && ok=0
    (( $ok == 1 )) && echo yes
    exit 0
fi

getenvdata

if [[ $1 == config ]]; then
cat <<EOF
graph_title Apache mod_cache_disk usage
graph_title Number of entries in mod_cache_disk Apache cache
graph_args --base 1000 -l 0
graph_vlabel Y
graph_category webserver
graph_order ${fieldnames[*]} total
total.draw LINE1
total.label all
total.type GAUGE
total.min 0
EOF

    let i=0
    while (( $i < ${#fieldnames[*]} )); do
        string=${fieldnames[$i]}
        label="${labels[$i]}"
        colour="${colours[$i]}"
        cat <<EOF
${string}.draw AREASTACK
${string}.label ${label}
${string}.colour ${colour}
EOF
        ((i++))
    done
    exit 0
fi

total=$(htcacheclean -a -p "$my_cache_path"|wc -l)
asset_count=$(htcacheclean -a -p "$my_cache_path"|egrep -o "\.($(echo ${fieldnames[*]}|tr ' ' '|'))"|sort|uniq --count)
printf "total.value %d\n" "$total"
for i in ${fieldnames[*]}; do
    c=$(echo "$asset_count"|sed -rn "/$i/s;^\s*([0-9]+).*;\1;p")
    [[ -z $c ]] && c=U
    printf "%s.value %s\n" "$i" "$c"
done

exit 0