Empty an entire S3 bucket, including object versions

emptyb

#!/usr/bin/env bash
#
# empty entire S3 bucket
# usage: emptyb <bucket>
#
# author: Erhhung Yuan <erhhung@alum.mit.edu>

bucket=$1

if [ -z "$bucket" ]; then
  echo "Empty entire S3 bucket"
  echo "Usage: emptyb <bucket>"
  exit
fi

# require given commands
# to be $PATH accessible
# _require foo bar || return 1
_require() {
  for bin in "$@"; do
    if ! hash $bin 2> /dev/null; then
      echo >&2 "Please install \"$_\" first!"
      return 1
    fi
  done
}
_require aws jq || exit 1

PAGE_SIZE=500

# _delobjs <type> <label>
_delobjs() {
  type=$1 label=$2
  opts=() token=""

  while [ "$token" != "null" ]; do
    page="$(aws s3api list-object-versions \
              --bucket $bucket \
              --query="[{
                Objects: ${type}[].{
                  Key: Key,
                  VersionId: VersionId
                }},
                NextToken]" \
               "${opts[@]}" \
              --page-size $PAGE_SIZE \
              --max-items $PAGE_SIZE \
              --output json)" || exit $?

     objs="$(jq '.[0] | .+={Quiet: true}' <<< "$page")"
    count="$(jq '.Objects | length' <<< "$objs")"
    token="$(jq -r '.[1]' <<< "$page")"
    opts=(--starting-token "$token")

    if [[ $count -gt 0 ]]; then
      aws s3api delete-objects \
        --bucket $bucket \
        --delete "$objs"
      jq -r '.Objects[].Key | "['$label'] "+.' <<< "$objs"
    fi
  done
}

_delobjs Versions      VER
_delobjs DeleteMarkers DEL