You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: cookie.rb
    path of file: ./repos/stackneveroverflow/vendor/bundle/ruby/2.3.0/gems/rack-2.0.3/lib/rack/session
    
    the code of the file until where you have to start completion: require 'openssl'
require 'zlib'
require 'rack/request'
require 'rack/response'
require 'rack/session/abstract/id'
require 'json'

module Rack

  module Session

    # Rack::Session::Cookie provides simple cookie based session management.
    # By default, the session is a Ruby Hash stored as base64 encoded marshalled
    # data set to :k
    
      def delete_session(req, session_id, options)
        # Nothing to do here, data is in the client
        generate_sid unless options[:drop]
      end

      def digest_match?(data, digest)
        return unless data && digest
        @secrets.any? do |secret|
          Rack::Utils.secure_compare(digest, generate_hmac(data, secret))
        end
      end

      def generate_hmac(data, secret)
        OpenSSL::HMAC.hexdigest(@hmac.new, secret, data)
      end

      def secure?(options)
        @secrets.size >= 1 ||
        (options[:coder] && options[:let_coder_handle_secure_encoding])
      end

    end