title: How to update specific attributes from restricted model using Best_In_Place and Cancan
body: <p>How can say a 'teacher' update only certain attribute of a model (say model 'book') while he/she could not update the other attributes of that model when using both Cancan and Best_In_Place. I understand that attribute-authorization is not yet supported in Cancan as it is still under development in 2.0 so the first thing I thought was to use something like this:</p>
  
  <pre><code>cannot :all, Book
  if is_teacher?
      can :update_certain_attribute, Book
  end
  </code></pre>
  
  <p>But since I wanted to use Best_In_Place, my preliminary research tells me that I could only use attributes for Best_In_Place update 
  like below</p>
  
  <pre><code>&lt;%= best_in_place @book, :certain_attribute, :type =&gt; :input %&gt;
  </code></pre>
  
  <p>and not methods :</p>
  
  <pre><code>&lt;%= best_in_place @book, :update_certain_attribute, :type =&gt; :input %&gt;
  </code></pre>
  
  <p>What's the best way to deal with this? Thanks :)</p>