title: How to serialize virtual attributes in rails 5
body: <p>I want to searilaize a couple of virtual attribute defined in my model like below</p>
  
  <pre><code>class User
    attribute :full_name, :string
    attribute :mobile,    :integer
    serialize :properties
  end
  </code></pre>
  
  <p>I wants to save <code>full_name</code> and <code>mobile</code> in hash format in properties column of users table. How can I do that, Please help.</p>