Cloudflare DynDNS

clfdns.rb

#! /usr/bin/env ruby

require 'net/http'
require 'cloudflare'

# Email used for login
CLOUDFLARE_EMAIL = ENV["CLOUDFLARE_EMAIL"]

# API Key, can be found here => https://www.cloudflare.com/a/account/my-account
CLOUDFLARE_API_KEY = ENV["CLOUDFLARE_API_KEY"]

# The zone (aka domain) this is for, e.g. 'example.com'
CLOUDFLARE_ZONE = ENV["CLOUDFLARE_ZONE"]

# The specific record name to edit, e.g. 'record.example.com'
CLOUDFLARE_RECORD_NAME = ENV["CLOUDFLARE_RECORD_NAME"]

def get_ip
  Net::HTTP.get(URI.parse('http://canihazip.com/s'))
end

def update_cloudflare(ip)
  cf = CloudFlare::connection(CLOUDFLARE_API_KEY, CLOUDFLARE_EMAIL)
  begin
    rec_id = ''
    records = cf.rec_load_all(CLOUDFLARE_ZONE)
    records['response']['recs']['objs'].each do |record|
      if record['name'] == CLOUDFLARE_RECORD_NAME
        rec_id = record['rec_id']
        break
      end
    end
    # Sending '1' for the TTL = 'automatic' meaning approx. 300 (5 minutes)
    cf.rec_edit(CLOUDFLARE_ZONE, 'A', rec_id, CLOUDFLARE_RECORD_NAME, ip, 1)
  rescue => e
    puts e.message
  else
    puts "Successfully updated A record for #{CLOUDFLARE_RECORD_NAME} to #{ip}"
  end
end

update_cloudflare(get_ip)

See the blog post for context: https://blog.kilian.io/cheap-dyndns-alternative/

why only a gist?

a dedicated repo feels overkill for a single file. an reason a gist is no good?