how can I redefine the ruby and rails request.ip and request.remote_ip methods?

Question

I've a rails app and I'm trying to overload the request.remote_ip and request.ip in order to use the cloudflare header (HTTP_CF_CONNECTING_IP) if it's present... I've tried these, but none of them work:

module Rack
  class Request
    class << self
      def ip
        @ip ||= (@env['HTTP_CF_CONNECTING_IP'] || super)
      end
    end
  end
end

module ActionDispatch
  class Request < Rack::Request
    class << self
      def remote_ip
        @remote_ip ||= (@env['HTTP_CF_CONNECTING_IP'] || super)
      end
    end
  end
end

I can't use an extra method like

def connecting_ip
  @env['HTTP_CF_CONNECTING_IP'] || request.remote_ip
end

in the application_controller because I've some other gems (like devise) which use request.ip

Thank you!

Answer 1

I believe request is an instance. But you are defining class methods. Remove the class << self nonsense and you instead be redefining instance methods.

Just a note though, this sounds kind of crazy. Be careful in there. Frameworks dont always like having their guts rearranged.

---

Your error message when using instance methods means something else is going on. super calls the superclass implementation. But when you reopen a class and override things, you are literally overwriting the original implementation. Since the method doesn't exist in the superclass, super doesn't work.

Instead you can use alias to save the original implementation before you declare the new method that would replace it.

module ActionDispatch
  class Request < Rack::Request
    alias :remote_ip_orig :remote_ip
    def remote_ip
      @remote_ip ||= (@env['HTTP_CF_CONNECTING_IP'] || remote_ip_orig)
    end
  end
end