FRITZ!Box DynDNS via Cloudflare

docker-compose.yml

# ldap
version: "3.1"

services:

  dns-service:
    image: dns-service
    networks:
      - web
    ports:
      - "8180:80"
    deploy:
      labels:
        - "traefik.backend=ldap-admin"
        - "traefik.docker.network=web"
        - "traefik.enable=true"
        - "traefik.frontend.rule=Host:127.0.0.1"
        - "traefik.port=80"
      restart_policy:
        condition: on-failure

networks:
  web:
    external: true

Dockerfile

FROM php:7.3.0-apache
COPY . /var/www/html/
WORKDIR /var/www/html

updateDNS.php

<?php
/*
FRITZ!Box DynDNS Howto:
Update-URL:	http://your-domain.tld/filename.php?user=<username>&pass=<pass>&hostname=<domain>&myip=<ipaddr>
Domainname:	dyndns.your-domain.tld
Username:	your-cloudflare-email-address
Password:	your-cloudflare-api-token
*/

// static config:
$cfZoneId =	"..."; //put your CloudFlare Zone ID here
$cfDnsId =	"..."; // put your CloudFlare DNS Identifier here

// dynamic config
$cfEmail =	$_GET['user'];
$cfApikey =	$_GET['pass'];
$updateDomain =	$_GET['hostname'];
$ipAddr =	$_GET['myip'];

$cfUrl =	"https://api.cloudflare.com/client/v4/zones/".$cfZoneId."/dns_records/".$cfDnsId;

$data = array(
  "type" => "A",
  "name" => "{$updateDomain}",
  "content" => "{$ipAddr}",
  "ttl" => 120,
  "proxied" => false,
  );

$curl = curl_init($cfUrl);

curl_setopt($curl, CURLOPT_CUSTOMREQUEST, "PUT");
curl_setopt($curl, CURLOPT_HEADER, false);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
curl_setopt($curl, CURLOPT_HTTPHEADER, array('Content-Type: application/json',"X-Auth-Email: $cfEmail","X-Auth-Key: $cfApikey"));
curl_setopt($curl, CURLOPT_POSTFIELDS, json_encode($data));


$response = curl_exec($curl);
if (!$response) {
    die("Connection failure.");
}else{
	var_dump($response);
}

?>