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:
#
# * <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 so you can
# restrict to the domain level. If you use a schema like www.example.com
# and want to share session with user.example.com set <tt>:domain</tt>
# to <tt>:all</tt>. Make sure to specify the <tt>:domain</tt> option with
# <tt>:all</tt> again when deleting keys.
#
# :domain => nil # Does not sets cookie domain. (default)
# :domain => :all # Allow the cookie for the top most level
# domain and subdomains.
#
# * <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+.
class Cookies
HTTP_HEADER = "Set-Cookie".freeze
TOKEN_KEY = "action_dispatch.secret_token".freeze
# Raised when storing more than 4K of session data.
class CookieOverflow < StandardError; end
class CookieJar < Hash #:nodoc:
# This regular expression is used to split the levels of a domain
# So www.example.co.uk gives:
# $1 => www.
# $2 => example
# $3 => co.uk
DOMAIN_REGEXP = /^(.*\.)*(.*)\.(...|...\...|....|..\...|..)$/
def self.build(request)
secret = request.env[TOKEN_KEY]
host = request.env["HTTP_HOST"]
new(secret, host).tap do |hash|
hash.update(request.cookies)
end
end
def initialize(secret = nil, host = nil)
@secret = secret
@set_cookies = {}
@delete_cookies = {}
@host = host
super()
end
# Returns the value of the cookie by +name+, or +nil+ if no such cookie exists.
def [](name)
super(name.to_s)
end
def handle_options(options) #:nodoc:
options[:path] ||= "/"
if options[:domain] == :all
@host =~ DOMAIN_REGEXP
options[:domain] = ".#{$2}.#{$3}"
end
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)
handle_options(options)
@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 <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!
handle_options(options)
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(headers)
@set_cookies.each { |k, v| ::Rack::Utils.set_cookie_header!(headers, k, v) }
@delete_cookies.each { |k, v| ::Rack::Utils.delete_cookie_header!(headers, 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']
cookie_jar.write(headers)
if headers[HTTP_HEADER].respond_to?(:join)
headers[HTTP_HEADER] = headers[HTTP_HEADER].join("\n")
end
end
[status, headers, body]
end
end
end
