Returns an array of subfolders for a given path on S3, with aws-sdk (ruby)

folders.rb

    # Returns an array of subfolders for a given path
    def folders(path = '/')
      objs        = []
      next_marker = nil
      loop do
        response = Aws::S3::Client.new.list_objects(
          bucket: 'bucket',
          delimiter: "/",
          encoding_type: "url",
          marker: next_marker,
          prefix: File.join(path, "") # we need trailing slash
        )
        next_marker = response.next_marker
        objs += response.common_prefixes.map { |cp| File.basename(cp.prefix) }

        break unless response.is_truncated
      end

      objs
    end