#!/bin/bash

# -------------------------------------------------------------------------- #
# Copyright 2002-2014, OpenNebula Project (OpenNebula.org), C12G Labs        #
#                                                                            #
# Licensed under the Apache License, Version 2.0 (the "License"); you may    #
# not use this file except in compliance with the License. You may obtain    #
# a copy of the License at                                                   #
#                                                                            #
# http://www.apache.org/licenses/LICENSE-2.0                                 #
#                                                                            #
# Unless required by applicable law or agreed to in writing, software        #
# distributed under the License is distributed on an "AS IS" BASIS,          #
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   #
# See the License for the specific language governing permissions and        #
# limitations under the License.                                             #
#--------------------------------------------------------------------------- #

###############################################################################
# This script is used to monitor the free and used space of a datastore
###############################################################################

# -------- Set up the environment to source common tools & conf ------------

if [ -z "${ONE_LOCATION}" ]; then
    LIB_LOCATION=/usr/lib/one
else
    LIB_LOCATION=$ONE_LOCATION/lib
fi

. $LIB_LOCATION/sh/scripts_common.sh

DRIVER_PATH=$(dirname $0)
source ${DRIVER_PATH}/../libfs.sh

# -------- Get datastore arguments from OpenNebula core ------------

DRV_ACTION=$1
ID=$2

XPATH="${DRIVER_PATH}/../xpath.rb -b $DRV_ACTION"

unset i XPATH_ELEMENTS

while IFS= read -r -d '' element; do
    XPATH_ELEMENTS[i++]="$element"
done < <($XPATH     /DS_DRIVER_ACTION_DATA/DATASTORE/BASE_PATH)

BASE_PATH="${XPATH_ELEMENTS[0]}"

# ------------ Compute datastore usage -------------

if [ ! -d $BASE_PATH ]; then
    mkdir -p $BASE_PATH
fi

USED_MB=`du -sLm $BASE_PATH 2>/dev/null | cut -f1`
TOTAL_MB=`df -B1M -P $BASE_PATH 2>/dev/null | tail -n 1 | awk '{print $2}'`
FREE_MB=`df -B1M -P $BASE_PATH 2>/dev/null | tail -n 1 | awk '{print $4}'`

if [ -z "$USED_MB" -o -z "$TOTAL_MB" -o -z "$FREE_MB"]; then
    msg="Empty monitoring data"
    error_message "$msg: USED_MB=$USED_MB, TOTAL_MB=$TOTAL_MB, FREE_MB=$FREE_MB"
    exit 1
fi

MONITOR_DATA=$(cat <<EOF
USED_MB=$USED_MB
TOTAL_MB=$TOTAL_MB
FREE_MB=$FREE_MB
EOF
)

echo "$MONITOR_DATA"
