require "active_support/core_ext/object/blank" module ActionDispatch class Request def cookie_jar env['action_dispatch.cookies'] ||= Cookies::CookieJar.build(self) end end # 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: # # * :value - The cookie's value or list of values (as an array). # * :path - The path for which this cookie applies. Defaults to the root # of the application. # * :domain - The domain for which this cookie applies. # * :expires - The time at which this cookie expires, as a Time object. # * :secure - Whether this cookie is a only transmitted to HTTPS servers. # Default is +false+. # * :httponly - Whether this cookie is accessible via scripting or # only HTTP. Defaults to +false+. class Cookies # Raised when storing more than 4K of session data. class CookieOverflow < StandardError; end class CookieJar < Hash #:nodoc: def self.build(request) secret = request.env["action_dispatch.secret_token"] new(secret).tap do |hash| hash.update(request.cookies) end end def initialize(secret=nil) @secret = secret @set_cookies = {} @delete_cookies = {} super() end # 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 value = super(key.to_s, value) options[:path] ||= "/" @set_cookies[key] = options @delete_cookies.delete(key) value 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 []=, you can pass in # an options hash to delete cookies with extra data such as a :path. def delete(key, options = {}) options.symbolize_keys! options[:path] ||= "/" value = super(key.to_s) @delete_cookies[key] = options value end # Returns a jar that'll automatically set the assigned cookies to have an expiration date 20 years from now. Example: # # cookies.permanent[:prefers_open_id] = true # # => Set-Cookie: prefers_open_id=true; path=/; expires=Sun, 16-Dec-2029 03:24:16 GMT # # This jar is only meant for writing. You'll read permanent cookies through the regular accessor. # # This jar allows chaining with the signed jar as well, so you can set permanent, signed cookies. Examples: # # cookies.permanent.signed[:remember_me] = current_user.id # # => Set-Cookie: discount=BAhU--848956038e692d7046deab32b7131856ab20e14e; path=/; expires=Sun, 16-Dec-2029 03:24:16 GMT def permanent @permanent ||= PermanentCookieJar.new(self, @secret) end # Returns a jar that'll automatically generate a signed representation of cookie value and verify it when reading from # the cookie again. This is useful for creating cookies with values that the user is not supposed to change. If a signed # cookie was tampered with by the user (or a 3rd party), an ActiveSupport::MessageVerifier::InvalidSignature exception will # be raised. # # This jar requires that you set a suitable secret for the verification on your app's config.secret_token. # # Example: # # cookies.signed[:discount] = 45 # # => Set-Cookie: discount=BAhpMg==--2c1c6906c90a3bc4fd54a51ffb41dffa4bf6b5f7; path=/ # # cookies.signed[:discount] # => 45 def signed @signed ||= SignedCookieJar.new(self, @secret) end def write(response) @set_cookies.each { |k, v| response.set_cookie(k, v) } @delete_cookies.each { |k, v| response.delete_cookie(k, v) } end end class PermanentCookieJar < CookieJar #:nodoc: def initialize(parent_jar, secret) @parent_jar, @secret = parent_jar, secret end def []=(key, options) if options.is_a?(Hash) options.symbolize_keys! else options = { :value => options } end options[:expires] = 20.years.from_now @parent_jar[key] = options end def signed @signed ||= SignedCookieJar.new(self, @secret) end def method_missing(method, *arguments, &block) @parent_jar.send(method, *arguments, &block) end end class SignedCookieJar < CookieJar #:nodoc: MAX_COOKIE_SIZE = 4096 # Cookies can typically store 4096 bytes. SECRET_MIN_LENGTH = 30 # Characters def initialize(parent_jar, secret) ensure_secret_secure(secret) @parent_jar = parent_jar @verifier = ActiveSupport::MessageVerifier.new(secret) end def [](name) if signed_message = @parent_jar[name] @verifier.verify(signed_message) end rescue ActiveSupport::MessageVerifier::InvalidSignature nil end def []=(key, options) if options.is_a?(Hash) options.symbolize_keys! options[:value] = @verifier.generate(options[:value]) else options = { :value => @verifier.generate(options) } end raise CookieOverflow if options[:value].size > MAX_COOKIE_SIZE @parent_jar[key] = options end def method_missing(method, *arguments, &block) @parent_jar.send(method, *arguments, &block) end protected # To prevent users from using something insecure like "Password" we make sure that the # secret they've provided is at least 30 characters in length. def ensure_secret_secure(secret) if secret.blank? raise ArgumentError, "A secret is required to generate an " + "integrity hash for cookie session data. Use " + "config.secret_token = \"some secret phrase of at " + "least #{SECRET_MIN_LENGTH} characters\"" + "in config/application.rb" end if secret.length < SECRET_MIN_LENGTH raise ArgumentError, "Secret should be something secure, " + "like \"#{ActiveSupport::SecureRandom.hex(16)}\". The value you " + "provided, \"#{secret}\", is shorter than the minimum length " + "of #{SECRET_MIN_LENGTH} characters" end end end def initialize(app) @app = app end def call(env) status, headers, body = @app.call(env) if cookie_jar = env['action_dispatch.cookies'] response = Rack::Response.new(body, status, headers) cookie_jar.write(response) response.to_a else [status, headers, body] end end end end