print CloudTrail event counts by username in all regions for the given time range

cloudtrail_overview.sh

#!/bin/bash

set -euo pipefail
IFS=$'\n\t'

if [ "$#" -ne 2 ]; then
    echo 'print CloudTrail event counts by username in all regions for the given time range.'
    echo 'usage:'
    echo "  $0" 'start-time end-time'
    echo 'example:'
    echo "  $0" '$(date --date=yesterday --iso-8601=seconds) $(date --date=now --iso-8601=seconds)'
    exit 1
fi

start_time=$1
end_time=$2

echo --start-time $1
echo --end-time $2
echo

regions=$(aws ec2 describe-regions --query Regions[].RegionName --output text)
for region in $regions; do
    echo $region -------------------------------------------------------------
    aws --region $region cloudtrail lookup-events \
        --no-paginate \
        --query 'Events[].[Username,EventName]' \
        --output text \
        --start-time "$start_time" \
        --end-time "$end_time" \
        | sort | uniq -c
    echo
done