#!/bin/sh -e
#
# ec2_cost: approximate EC2 cost (USD) of the current instance
#
# Copyright (C) 2008 Canonical Ltd.
# Copyright (C) 2011-2014 Dustin Kirkland
#
# Authors: Dustin Kirkland <[email protected]>
#
# 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 3 of the License.
#
# 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, see <http://www.gnu.org/licenses/>.

# Data Transfer Cost Basis
# Incoming $0.01/GB
# Outgoing $0.12/GB
# (This gets more complex if you use >10TB/mo)
RX_RATE="0.01"
TX_RATE="0.12"

__ec2_cost_detail() {
DETAIL=1
__ec2_cost
}

__ec2_cost() {
local zone type file_to_stat cpu mem rate hours tx_gb rx_gb network_cost uptime_cost total_cost interface cache="$BYOBU_RUN_DIR/cache.$BYOBU_BACKEND/ec2_cost"
if [ -s "$cache.rate" ]; then
read rate < "$cache.rate"
elif metadata_available; then
# Try to use metadata service
[ -s "$cache.zone" ] || wget -q -O- http://169.254.169.254/latest/meta-data/placement/availability-zone </dev/null >"$cache.zone" 2>/dev/null &
sleep 0.02
[ -s "$cache.zone" ] && read zone < "$cache.zone"
zone=${zone%%[a-z]}
[ -s "$cache.type" ] || wget -q -O- http://169.254.169.254/latest/meta-data/instance-type </dev/null >"$cache.type" 2>/dev/null &
sleep 0.02
[ -s "$cache.type" ] && read type < "$cache.type"
$BYOBU_PREFIX/lib/byobu/include/ec2instancespricing.py --type ondemand --filter-region $zone --filter-type $type --filter-os-type linux --format csv | tail -n1 > "$cache.rate"
read rate < "$cache.rate"
fi
if [ -z "$rate" ]; then
# Unknown rate, exit immediately
# Rate estimation is now deprecated
return
fi
rate=${rate##*,}
file_to_stat="/etc/hostname"
hours=$(((`date +%s` - `stat --printf %Y $file_to_stat`) / 60 / 60 + 1))
# Auto detect network interface
[ -r "/proc/net/route" ] || return
interface=$(tail -n1 /proc/net/route | awk '{print $1}')
local iface rbytes rpackets rerrs rdrop rfifo rframe rcompressed rmulticast tbytes tpackets terrs tdrop tfifo tcolls tcarrier tcompressed
while read iface rbytes rpackets rerrs rdrop rfifo rframe rcompressed rmulticast tbytes tpackets terrs tdrop tfifo tcolls tcarrier tcompressed; do
case "$iface" in
${interface}:)
tx_gb=${tbytes}
rx_gb=${rbytes}
break;
;;
${interface}:*)
# Interface and rbytes got munged together
tx_gb=${rmulticast##*:}
rx_gb=${iface##*:}
break;
;;
esac
if [ "$iface" = "${interface}:" ]; then
tx_gb=${tbytes}
rx_gb=${rbytes}
break
fi
done < /proc/net/dev
tx_gb=$(printf "%s" ${tx_gb} | awk '{ printf "%f", $1 / 1024 / 1024 / 1024 }')
rx_gb=$(printf "%s" ${rx_gb} | awk '{ printf "%f", $1 / 1024 / 1024 / 1024 }')
network_cost=`printf "%s %s %s %s" "$tx_gb" "$TX_RATE" "$rx_gb" "$RX_RATE" | awk '{printf "%f %f", $1*$2, $3*$4}' | awk '{printf "%f", $1 + $2}'`
# Calculate uptime cost
uptime_cost=`printf "%s" "$hours" | awk "{printf \"%f\", "$rate" * $hours}"`
total_cost=`printf "%s %s" "$network_cost" "$uptime_cost" | awk '{printf "%.2f", $1 + $2}'`
if [ "$DETAIL" = "1" ]; then
echo "================================================"
echo "Estimated cost in Amazon's EC2 since last reboot"
echo "================================================"
echo " Network sent: $tx_gb GB @ \$$RX_RATE/GB"
echo " Network recv: $rx_gb GB @ \$$TX_RATE/GB"
echo " Network cost: \$$network_cost"
echo "------------------------------------------------"
echo " Uptime: $hours hr @ \$$rate/hr"
echo " Uptime cost: \$$uptime_cost"
echo "------------------------------------------------"
echo "Total cost: ~\$$total_cost"
echo "================================================"
return
fi
[ -n "$total_cost" ] || return
color K G; printf "A\$"; color -; color b K G; printf "%s" "$total_cost"; color --
}

# vi: syntax=sh ts=4 noexpandtab