def to_format
      if !get? && has_errors? && !response_overridden?
        display_errors
      elsif has_view_rendering? || response_overridden?
        default_render
      else
        api_behavior
      end
    rescue ActionView::MissingTemplate
      api_behavior
    end
def to_format
      if !get? && has_errors? && !response_overridden?
        display_errors
      elsif has_view_rendering? || response_overridden?
        default_render
      else
        api_behavior
      end
    rescue ActionView::MissingTemplate
      api_behavior
    end
All other formats follow the procedure below. First we try to render a
 template, if the template is not available, we verify if the resource
 responds to :to_format and display it.