rails--rails/actionpack/lib/action_controller/metal/cookies.rb

module ActionController #:nodoc:
  # Cookies are read and written through ActionController#cookies.
  #
  # The cookies being read are the ones received along with the request, the cookies
  # being written will be sent out with the response. Reading a cookie does not get
  # the cookie object itself back, just the value it holds.
  #
  # Examples for writing:
  #
  #   # Sets a simple session cookie.
  #   cookies[:user_name] = "david"
  #
  #   # Sets a cookie that expires in 1 hour.
  #   cookies[:login] = { :value => "XJ-122", :expires => 1.hour.from_now }
  #
  # Examples for reading:
  #
  #   cookies[:user_name] # => "david"
  #   cookies.size        # => 2
  #
  # Example for deleting:
  #
  #   cookies.delete :user_name
  #
  # Please note that if you specify a :domain when setting a cookie, you must also specify the domain when deleting the cookie:
  #
  #  cookies[:key] = {
  #    :value => 'a yummy cookie',
  #    :expires => 1.year.from_now,
  #    :domain => 'domain.com'
  #  }
  #
  #  cookies.delete(:key, :domain => 'domain.com')
  #
  # The option symbols for setting cookies are:
  #
  # * <tt>:value</tt> - The cookie's value or list of values (as an array).
  # * <tt>:path</tt> - The path for which this cookie applies.  Defaults to the root
  #   of the application.
  # * <tt>:domain</tt> - The domain for which this cookie applies.
  # * <tt>:expires</tt> - The time at which this cookie expires, as a Time object.
  # * <tt>:secure</tt> - Whether this cookie is a only transmitted to HTTPS servers.
  #   Default is +false+.
  # * <tt>:httponly</tt> - Whether this cookie is accessible via scripting or
  #   only HTTP. Defaults to +false+.
  module Cookies
    extend ActiveSupport::Concern

    include RackDelegation

    included do
      helper_method :cookies
    end

  protected
    # Returns the cookie container, which operates as described above.
    def cookies
      @cookies ||= CookieJar.build(request, response)
    end
  end

  class CookieJar < Hash #:nodoc:
    def self.build(request, response)
      new.tap do |hash|
        hash.update(request.cookies)
        hash.response = response
      end
    end

    attr_accessor :response

    # Returns the value of the cookie by +name+, or +nil+ if no such cookie exists.
    def [](name)
      super(name.to_s)
    end

    # Sets the cookie named +name+. The second argument may be the very cookie
    # value, or a hash of options as documented above.
    def []=(key, options)
      if options.is_a?(Hash)
        options.symbolize_keys!
        value = options[:value]
      else
        value = options
        options = { :value => value }
      end

      super(key.to_s, value)
      
      options[:path] ||= "/"
      response.set_cookie(key, options)
    end

    # Removes the cookie on the client machine by setting the value to an empty string
    # and setting its expiration date into the past. Like <tt>[]=</tt>, you can pass in
    # an options hash to delete cookies with extra data such as a <tt>:path</tt>.
    def delete(key, options = {})
      options.symbolize_keys!
      options[:path] ||= "/"
      value = super(key.to_s)
      response.delete_cookie(key, options)
      value
    end
  end
end