Cloudflar Dynamic DNS Script

cfupdater

#!/bin/sh

zone_identifier=""
record_name=""
auth_token=""

get_response=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/${zone_identifier}/dns_records?name=${record_name}&type=A" -H "Authorization: Bearer ${auth_token}" -H "Accept: application/json")

get_success=$(echo ${get_response} | jq .success)

if [ "${get_success}" != "true" ]; then
  >&2 echo "API GET failed, cannot fetch DNS record."
  exit 1
fi

count=$(echo ${get_response} | jq .result_info.count)

if [ "${count}" != "1" ]; then
  >&2 echo "No existing A record."
fi

record=$(echo ${get_response} | jq .result[0])
record_id=$(echo ${record} | jq -r .id)
record_content=$(echo ${record} | jq -r .content)

# Check for current external network IP
ip=$(curl -s https://icanhazip.com/)

if [ "${ip}" != "" ]; then
  echo "Fetched current external network IP: ${ip}"
else
  >&2 echo "Network error, cannot fetch external network IP."
fi

if [ "${ip}" = "${record_content}" ]; then
  echo "Update for A record ${record_name} cancelled; IP has not changed."
  exit 0
else
  echo "Different IP addresses detected, synchronizing..."
fi

data="{\"content\":\"${ip}\"}"
patch_response=$(curl -s -X PATCH "https://api.cloudflare.com/client/v4/zones/${zone_identifier}/dns_records/${record_id}" -H "Authorization: Bearer ${auth_token}" -H "Content-Type: application/json" --data ${data})
patch_success=$(echo ${patch_response} | jq .success)

if [ "${patch_success}" = "true" ]; then
  echo "Successfully updated A record for ${record_name}.\n  - Old value: ${record_content}\n  + New value: ${ip}"
  exit 0
else
  >&2 echo "APT PATCH failed, cannot update DNS record."
  exit 1
fi