Memoize Method calls based on params

memoize_extensions.rb

module MemoizeExtensions
  def memoize_methods(method_name, *params)
      @@hash ||= {}
      return @@hash[params] if @@hash[params]
      @@hash[params] = send(method_name, *params)
  end
end

class User < ActiveRecord::Base
  
  extend MemoizeExtensions
  
  scope :visible, -> { where(deleted: false) }
  scope :active, -> { where(active: true) }

  def self.fetch_all_users(filter)
    public_send(filter).all
  end
    
end
  
class UsersController < ApplicationController
  def index
    User.memoize_methods(:fetch_all_users, params[:filter_type].to_sym)
  end
end