# File lib/anemone/storage/mongodb.rb, line 27
      def []=(url, page)
        hash = page.to_hash
        BINARY_FIELDS.each do |field|
          hash[field] = BSON::Binary.new(hash[field]) unless hash[field].nil?
        end
        @collection.update(
          {'url' => page.url.to_s},
          hash,
          :upsert => true
        )
      end