Cloudflare V4 API DynDNS Updater for Synology Cloudstation

cloudflareddns.sh

#!/bin/sh

# cloudflareddns.sh - dynamic dns updater module for Synology
#
# Author:
#   Luca Kröger (LucaDev on Github)
#   Originally: Michael Wildman (http://mwild.me)
#
# Version:
#   0.3
#
# Description:
#   copy to /sbin/cloudflaredns.sh
#   make executable (chmod +x)
#   add the following entry to /etc.defaults/ddns_provider.conf
#
#       [CloudFlare]                                                                                                                                                
#           modulepath=/sbin/cloudflaredns.sh                                                                                                                   
#           queryurl=https://www.cloudflare.com/api_json.html?a=rec_edit&tkn=__PASSWORD__&email=__USERNAME__&z=__HOSTNAME__&content=__MYIP__ 
#   
#   (note that URL is not actually used, DSM will pass us the variables)
#   run a /zone to get the zone & rec id
#   (see https://api.cloudflare.com/)
#
# Changelog:
#   0.3:
#       - Update to Cloudflare V4 API
#
#   0.2:
#       - Simplified this thing to its most basic requirements (curl + logging)
#       - Now either returns 'good' or the result (no checking for cases -- the log was always more useful anyway!)
#
# Based on Brian Schmidt Pedersen (http://blog.briped.net) gratisdns.sh

# TODO
# read addition parameters from cloudflare api calls
#

# these variables are passed by DSM
# username is your email
__USERNAME__="$(echo ${@} | cut -d' ' -f1)"
# password is your cloudflare API key
__PASSWORD__="$(echo ${@} | cut -d' ' -f2)"
__HOSTNAME__="$(echo ${@} | cut -d' ' -f3)"
__MYIP__="$(echo ${@}  | cut -d' ' -f4)"

# log location
__LOGFILE__="/var/log/cloudflareddns.log"

# additional parameters needed for CloudFlare
__REC__="my.domain.tld"
__RECID__="myrecordid"
__ZONE__="myzoneid"

log() {
    __LOGTIME__=$(date +"%b %e %T")
    if [ "${#}" -lt 1 ]; then
        false
    else
        __LOGMSG__="${1}"
    fi
    if [ "${#}" -lt 2 ]; then
        __LOGPRIO__=7
    else
        __LOGPRIO__=${2}
    fi

    logger -p ${__LOGPRIO__} -t "$(basename ${0})" "${__LOGMSG__}"
    echo "${__LOGTIME__} $(basename ${0}) (${__LOGPRIO__}): ${__LOGMSG__}" >> ${__LOGFILE__}
}

__URL__="https://api.cloudflare.com/client/v4/zones/${__ZONE__}/dns_records/${__RECID__}"

# Update DNS record:
log "Updating with ${__MYIP__}..." 7
__RESPONSE__=$(curl --silent -X PUT "${__URL__}" -H "X-Auth-Email:${__USERNAME__}" \
-H "X-Auth-Key:${__PASSWORD__}" \
-H "Content-Type:application/json" \
--data '{"type":"A","name":"'${__REC__}'","content":"'${__MYIP__}'","data":{}}')

# Strip the result element from response json
__RESULT__=$(echo ${__RESPONSE__} | grep -o -E .success.:.[A-z]+.)

case ${__RESULT__} in
    '"success":true,')
        __STATUS__='good'
        true
        ;;
    *)
        __STATUS__="${__RESULT__}"
        log "__RESPONSE__=${__RESPONSE__}" 5
        false
        ;;
esac
log "Status: ${__STATUS__}" 6

printf "%s" "${__STATUS__}"