#!/bin/bash
#
# evaluate the current ram usage of every vm running on this host
#
# Date: 2011-09-09
# Author: Gerald Schnabel ger@ldschnabel.de
#
# Usage: Place in /etc/munin/plugins (or link it there using ln -s)
#
# This plugin has to run with the same user like the VirtualBox Server rans
# Update munin plugin-conf.d/munin-node file with
# [virtualbox_ram]
# user VIRTUAL_BOX_SERVER_USER
#
# Parameters understood:
#
# config (required)
# autoconf (optional - used by munin-config)
#
# Versions
# 2013-05-25 robi fix for handling vm names with dots and dashes; scale graph size by the max memory available; display GB on scales and legend
# 2011-09-22 ger@ldschnabel.de fix for handling vm names with spaces and setup metric period to get values
# 2011-09-09 ger@ldschnabel.de initial version

# Todo: sort
# readarray -t sorted < <(printf '%s\0' "${array[@]}" | sort -z | xargs -0n1)
# see http://stackoverflow.com/questions/7442417/how-to-sort-an-array-in-bash



if [ "$1" = "autoconf" ]; then
        echo yes
        exit 0
fi

if [ "$1" = "config" ]; then
        RAMTOT=$(free -b | grep Mem | awk '{print $2}')
        echo 'graph_title Memory usage of virtual machines'
        echo "graph_args --base 1024 -r --lower-limit 0 --upper-limit $RAMTOT --units-exponent 9"
        echo 'graph_vlabel GB'
        echo 'graph_info This graph shows the ram usage of every single VM process.'
        echo 'graph_category virtualization'
        echo 'graph_period second'
        I=0
        vboxmanage list vms | sed -r 's/^\"(.*)\" \{.*\}$/\1/' | while read -r VM_NAME; do
                VM_NAME_PRINT=$(echo -e "${VM_NAME}" | sed 's/[^A-Za-z0-9_]/_/g')
                echo "${VM_NAME_PRINT}.label ${VM_NAME}"
                echo "${VM_NAME_PRINT}.cdef ${VM_NAME_PRINT},1024,*"
                if [ "$I" -eq 0 ]; then
                        echo "${VM_NAME_PRINT}.draw AREA"
                else
                        echo "${VM_NAME_PRINT}.draw STACK"
                fi
                I=$(( I + 1 ))
        done
        exit 0
fi

vboxmanage metrics setup --period 5 --samples 3
sleep 5

vboxmanage list vms | sed -r 's/^\"(.*)\" \{.*\}$/\1/' | while read -r VM_NAME; do
        VM_NAME_PRINT=$(echo -e "${VM_NAME}" | sed 's/[^A-Za-z0-9_]/_/g') # s/[.]/_/g;s/[ ]/_/g;s/[-]/_/g
        vboxmanage metrics query "${VM_NAME}" RAM/Usage/Used | grep -E "^${VM_NAME}" | sed -r 's/^.* ([0-9]+) kB$/'"${VM_NAME_PRINT}"'.value \1/'
done