collect_mimes_from_class_level

# File actionpack/lib/action_controller/metal/mime_responds.rb, line 408
    def collect_mimes_from_class_level #:nodoc:
      action = action_name.to_s

      self.class.mimes_for_respond_to.keys.select do |mime|
        config = self.class.mimes_for_respond_to[mime]

        if config[:except]
          !config[:except].include?(action)
        elsif config[:only]
          config[:only].include?(action)
        else
          true
        end
      end
    end