Redis::Objects use case

admin.slim

p = user.ip_addresses.size
p = user.ip_addresses.value

application_controller.rb

class ApplicationController < ActionController::Base
  before_action :store_ip_addresses

  def store_ip_addresses
    return unless user_signed_in?
    current_user.ip_addresses << request.ip
  end
end

user.rb

class User < ApplicationRecord
  include Redis::Objects

  set :ip_addresses
end