docker-mailserver/target/bin/updatemailuser

#! /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=../scripts/helpers/index.sh
source /usr/local/bin/helpers/index.sh

DATABASE='/tmp/docker-mailserver/postfix-accounts.cf'

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

function __usage { echo 'Usage: updatemailuser <user@domain.tld> [password]' ; }

[[ -z ${USER} ]] && { __usage ; _exit_with_error 'No username specified' ; }

if [[ -z ${PASSWD} ]]
then
  read -r -s -p 'Enter Password: ' PASSWD
  echo
  [[ -z ${PASSWD} ]] && _exit_with_error 'Password must not be empty'
fi

HASH=$(doveadm pw -s SHA512-CRYPT -u "${USER}" -p "${PASSWD}")

touch "${DATABASE}"
_create_lock # Protect config file with lock to avoid race conditions
grep -qi "^$(_escape "${USER}")|" "${DATABASE}" 2>/dev/null || _exit_with_error "User \"${USER}\" does not exist"
sed -i "s ^""${USER}""|.* ""${USER}""|""${HASH}"" " "${DATABASE}"