title: Where to render comments controller in Rails on model validations failure?
body: <p>I have a simple Video model in my rails app that <code>has_many</code> comments. I am displaying these comments on the video's show page. When I submit the form everything works fine; however, if there are validation errors on the Comment model, then my system blows up. If there are validation errors on the Comment model, I would simply like to render the video's show page again, with the validation error styling showing. How do I do this inside of my create action? Thanks a lot!</p>
  
  <pre><code>class CommentsController &lt; ApplicationController
    def create
      @video = Video.find(params[:video_id])
      @comment = @video.comments.build(params[:comment])
      if @comment.save
        redirect_to @video, :notice =&gt; 'Thanks for posting your comments.'
      else
        render # what? What do I render in order to show the video page's show action with the validation error styling showing? Please help!
      end
    end
  end
  </code></pre>