inwx-ddns.sh

#!/usr/bin/env bash

###### Configuration ################################
USER=""
PASSWORD=""
IP_PROVIDER="ip4.ident.me"
#####################################################

INWX_API="https://dyndns.inwx.com/nic/update"

_CHECK_RESULT() {
  RESULT="${1}"
  if [ "${RESULT}" == "good" ] || [ "${RESULT}" == "nochg" ]; then
    echo "Done. Result was \"${RESULT}\"."
  else
    echo "Error: DynDNS update failed. Result was \"${RESULT}\"."
    exit 1
  fi
}

_RUN_CURL() {
  MY_IP="$(curl -sL "${IP_PROVIDER}")"
  IP_STATUS="$?"
  if [ -z "${MY_IP}" ] || [ "${IP_STATUS}" != "0" ]; then
    echo "Error: could not get IP address."
    exit 1
  fi
  RESULT="$(curl -sL -u "${USER}:${PASSWORD}" "${INWX_API}?myip=${MY_IP}")"
  _CHECK_RESULT "${RESULT}"
}

_RUN_WGET() {
  MY_IP="$(wget -O- -q "${IP_PROVIDER}")"
  IP_STATUS="$?"
  if [ -z "${MY_IP}" ] || [ "${IP_STATUS}" != "0" ]; then
    echo "Error: could not get IP address."
    exit 1
  fi
  RESULT="$(wget -O- -q --http-user "${USER}" --http-password "${PASSWORD}" "${INWX_API}?myip=${MY_IP}")"
  _CHECK_RESULT "${RESULT}"
}

if command -v curl > /dev/null; then
  _RUN_CURL
else
  _RUN_WGET
fi