s3_summary.sh

#!/bin/bash

if [ -z "${AWS_DEFAULT_PROFILE}" ]; then
	export AWS_DEFAULT_PROFILE=default
fi

set -e
set -u

START_TIME=$(date -u +%Y-%m-%dT00:00:00Z -d "1 day ago")
END_TIME=$(date -u +%Y-%m-%dT00:00:00Z)
PERIOD=86400

get_s3_bucket_size() {

	aws cloudwatch get-metric-statistics  --namespace AWS/S3 --metric-name BucketSizeBytes \
	--dimensions Name=BucketName,Value=$1 Name=StorageType,Value=StandardStorage --statistics Sum \
	--start-time $START_TIME --end-time $END_TIME --period $PERIOD |
	jq '.Datapoints[].Sum'
}

get_s3_object_num() {

	QUERY="[
  {
    \"Id\": \"objectCount\",
    \"MetricStat\": {
      \"Metric\": {
        \"Namespace\": \"AWS/S3\",
        \"MetricName\": \"NumberOfObjects\",
        \"Dimensions\": [
          {
            \"Name\": \"StorageType\",
            \"Value\": \"AllStorageTypes\"
          },
          {
            \"Name\": \"BucketName\",
            \"Value\": \"$1\"
          }
        ]
      },
      \"Period\": 86400,
      \"Stat\": \"Maximum\"
    }
  }
]"

	# result
    #"MetricDataResults": [
    #    {
    #        "Id": "objectCount",
    #        "Label": "NumberOfObjects",
    #        "Timestamps": [
    #            "2022-12-16T00:00:00+00:00"
    #        ],
    #        "Values": [
    #            4492.0
    #        ],
    #        "StatusCode": "Complete"
    #    }
    #],
    #"Messages": []
	#aws cloudwatch get-metric-data --metric-data-queries "${QUERY}" \
	#--start-time $START_TIME \
	#--end-time $END_TIME |
	#jq '.MetricDataResults[0].Values[0]'
	aws cloudwatch get-metric-statistics --namespace AWS/S3 --metric-name NumberOfObjects \
	--dimensions Name=BucketName,Value=$1 Name=StorageType,Value=AllStorageTypes --statistics Maximum \
	--start-time $START_TIME --end-time $END_TIME --period $PERIOD  |
	jq '.Datapoints[0].Maximum'
}

echo -e "Bucket\tRegion\tSize\tObjects"
for bucket in $(aws s3 ls | awk '{ print $3 }'); do
	region=$(aws s3api get-bucket-location --bucket $bucket | jq -r ".LocationConstraint")
	if [ "${region}" = "null" ]; then
		region="us-east-1"
	fi
	if [ "${region}" = "EU" ]; then
		region="eu-west-1"
	fi
	#size=$(aws s3 ls s3://${bucket}  --recursive --summarize | tail -1 | awk '{print $3}')
	size=$(get_s3_bucket_size $bucket)
	object_num=$(get_s3_object_num $bucket)
	echo -e "$bucket\t$region\t$size\t$object_num"
done