Automatically update Cloudflare DNS record for Dynamic IP environment

dns_update.py

import re
import json
import requests

IP_REGEX = re.compile(r"\nip=((?:[0-9]{,3}\.){3}[0-9]{,3})\n")

token = ""
zone = ""

CDN_CGI = "https://cloudflare.com/cdn-cgi/trace"
API_BASE = f"https://api.cloudflare.com/client/v4/zones/{zone}"

target_record = "example.com"

session = requests.Session()
session.headers.update({"Authorization": f"Bearer {token}"})

trace = session.get(CDN_CGI)
current_ip = IP_REGEX.search(trace.text).group(1)

print("Currently detected external IP:", current_ip)

records = session.get(API_BASE + "/dns_records")

record_id, record_ip = [
    (record['id'], record['content']) for record in records.json()['result']
    if record['name'] == target_record
][0]

print("Record ID:", record_id, "Registered IP:", record_ip)

if record_ip != current_ip:
    print("IP changed! Updating DNS record...")
    r = session.put(
        API_BASE + f"/dns_records/{record_id}",
        json={
            "name": target_record,
            "content": current_ip,
            "type": "A"
        }
    )
    print(json.dumps(r.json(), indent=4))