#!/bin/bash
if [ `uname` = "Darwin" ]; then
    start_time=`date -u -v-30M "+%Y-%m-%dT%H:%M:%SZ"`
else
    start_time=`date -u -d "30 minute ago" "+%Y-%m-%dT%H:%M:%SZ"`
fi
end_time=`date -u "+%Y-%m-%dT%H:%M:%SZ"`
period=300
statistics=Average

args_list=`aws cloudwatch list-metrics | jq -r '.Metrics[] | "--namespace " + .Namespace + " --metric-name " + .MetricName + " --dimensions " + ( .Dimensions[] | "Name=" + .Name + ",Value=" + .Value)'`

echo "$args_list" | while read line
do
    aws cloudwatch get-metric-statistics $line \
        --start-time $start_time \
        --end-time $end_time \
        --period $period \
        --statistics $statistics
done

# 最新データを取りたい場合は以下でフィルタ
# jq '.Datapoints | sort_by(.Timestamp) | reverse| .[0]'