docker-mailserver/target/bin/setquota

#! /bin/bash

# ? This is done to ignore the message "Make sure not to read and write
# ? the same file in the same pipeline", which is a result of ${DATABASE}
# ? being used below. (This disables the message file-wide.)
# shellcheck disable=SC2094

# shellcheck source=../bin-helper.sh
. /usr/local/bin/bin-helper.sh

DATABASE=${DATABASE:-/tmp/docker-mailserver/dovecot-quotas.cf}
USER_DATABASE=${USER_DATABASE:-/tmp/docker-mailserver/postfix-accounts.cf}

USER="${1}"
shift
QUOTA="${*}"

function usage  { echo "Usage: setquota <user@domain> [<quota>]" ; }

[[ -z ${USER} ]] && { usage ; errex "no username specified" ; }
[[ "${USER}" =~ .*\@.* ]] || { usage ; errex "username must include the domain" ; }

if ! grep -qE "^${USER}\|" "${USER_DATABASE}"
then
  usage; errex "user ${USER} does not exist"
fi

# check quota
if [[ -n ${QUOTA} ]] && ! echo "${QUOTA}" | grep -qE "^([0-9]+(B|k|M|G|T)|0)\$"
then
  usage
  errex "invalid quota format. e.g. 302M (B (byte), k (kilobyte), M (megabyte), G (gigabyte) or T (terabyte))"
fi

# Protect config file with lock to avoid race conditions
touch "${DATABASE}"
(
  flock -e 200

  if [ -z "${QUOTA}" ]; then
    read -r -s "Enter quota (e.g. 10M): " QUOTA
    echo
    [[ -z "${QUOTA}" ]] && errex "Quota must not be empty. Use 0 for unlimited quota"
  fi

  # check quota
  if [[ -n ${QUOTA} ]] && ! echo "${QUOTA}" | grep -qE "^([0-9]+(B|k|M|G|T)|0)\$"
  then
    usage
    errex "invalid quota format. e.g. 302M (B (byte), k (kilobyte), M (megabyte), G (gigabyte) or T (terabyte))"
  fi

  delquota "${USER}"
  echo "${USER}:${QUOTA}" >>"${DATABASE}"
) 200< "${DATABASE}"