gistfile1.rbx

class ApplicationController < AC::Base

   def with_etags( *etag, &block )
    etag = supplement_etag!( etag ).compact
    logger.info "** Etag source: #{etag.inspect}"
    response.last_modified = last_modified_for_etag( etag ).sort.last || now
    logger.info "** Response Last Modified: #{response.last_modified}"
    response.etag = etag
    logger.info "** Response Etag: #{response.etag.inspect}"
    if request.fresh?(response)
      logger.info "** Not Modified"
      head :not_modified
    else
      logger.info "** Modified"
      yield if block_given?
    end  
  end    
  
  def supplement_etag!( etag )
    etag.flatten + etag_current_user + etag_session + etag_params + etag_revision
  end
  
  def etag_current_user
    Array( current_user )
  end
  
  def etag_session
    Array( session.data.values )
  end
  
  def etag_params
    params.values
  end
  
  def etag_revision
    Array( ENV["RAILS_ASSET_ID"] || 'none' )
  end
  
  def last_modified_for_etag( etag )
    etag.flatten.reject{|e| !e.respond_to?(:updated_at) }.map{|e| e.updated_at }
  end

end