Cloudflare API v4 Dynamic DNS Update in Bash

README.md

Cloudflare DDNS bash client with systemd

This is a bash script to act as a Cloudflare DDNS client, useful replacement for ddclient.

How to use?

1. Put the cfupdater file to /usr/local/bin
2. chmod +x /usr/local/bin/cfupdater
3. Create a systemd service unit at /etc/systemd/system/, the cfupdate.service is shown as an example.
4. Create a systemd timer unit at the same location of the service unit, the cfupdate.timer is shown as an example.

Note

The default cfupdate.timer is set to execute the script every minute.
Please keep in mind not to spam the API or you will be rate limited.

A quote from Cloudflare FAQ:

All calls through the Cloudflare Client API are rate-limited to 1200 every 5 minutes.

-- https://support.cloudflare.com/hc/en-us/articles/200171456

cfupdate.service

[Unit]
Description=Cloudflare DDNS service
After=network.target

[Service]
Type=oneshot
ExecStart=/usr/local/bin/cfupdater

[Install]
WantedBy=multi-user.target

cfupdate.timer

[Unit]
Description=Run cfupdate.service every minute

[Timer]
OnCalendar=*:0/1

cfupdater

#!/bin/bash

# Forked by benkulbertis/cloudflare-update-record.sh
# CHANGE THESE
auth_email="[email protected]"            # The email used to login 'https://dash.cloudflare.com'
auth_key="f1nd7h47fuck1n6k3y1ncl0udfl4r3c0n50l3"   # Top right corner, "My profile" > "Global API Key"
zone_identifier="f1nd7h3fuck1n6z0n31d3n71f13r4l50" # Can be found in the "Overview" tab of your domain
record_name="example.org"                          # Which record you want to be synced

# DO NOT CHANGE LINES BELOW
ip=$(curl -s https://ipv4.icanhazip.com/)

# SCRIPT START
echo "[Cloudflare DDNS] Check Initiated" | systemd-cat

# Seek for the record
record=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records?name=$record_name" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json")

# Can't do anything without the record
if [[ $record == *"\"count\":0"* ]]; then
  echo -e "Record does not exist, perhaps create one first?" | systemd-cat -p crit
  exit 1
fi

# Set existing IP address from the fetched record
old_ip=$(echo "$record" | grep -Po '(?<="content":")[^"]*' | head -1)

# Compare if they're the same
if [ $ip == $old_ip ]; then
  echo "IP has not changed." | systemd-cat -p notice
  exit 0
fi

# Set the record identifier from result
record_identifier=$(echo "$record" | grep -Po '(?<="id":")[^"]*' | head -1)

# The execution of update
update=$(curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records/$record_identifier" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json" --data "{\"id\":\"$zone_identifier\",\"type\":\"A\",\"proxied\":false,\"name\":\"$record_name\",\"content\":\"$ip\"}")

# The moment of truth
case "$update" in
*"\"success\":false"*)
  echo -e "[Cloudflare DDNS] Update failed for $record_identifier. DUMPING RESULTS:\n$update" | systemd-cat -p err
  exit 1;;
*)
  echo "[Cloudflare DDNS] IP synced to: $ip" | systemd-cat -p notice;;
esac