class ActionDispatch::Cookies

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 of writing:

# Sets a simple session cookie.
# This cookie will be deleted when the user's browser is closed.
cookies[:user_name] = "david"

# Assign an array of values to a cookie.
cookies[:lat_lon] = [47.68, -122.37]

# Sets a cookie that expires in 1 hour.
cookies[:login] = { value: "XJ-122", expires: 1.hour.from_now }

# Sets a signed cookie, which prevents users from tampering with its value.
# The cookie is signed by your app's <tt>config.secret_key_base</tt> value.
# It can be read using the signed method <tt>cookies.signed[:name]</tt>
cookies.signed[:user_id] = current_user.id

# Sets a "permanent" cookie (which expires in 20 years from now).
cookies.permanent[:login] = "XJ-122"

# You can also chain these methods:
cookies.permanent.signed[:login] = "XJ-122"

Examples of reading:

cookies[:user_name]    # => "david"
cookies.size           # => 2
cookies[:lat_lon]      # => [47.68, -122.37]
cookies.signed[:login] # => "XJ-122"

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[:name] = {
  value: 'a yummy cookie',
  expires: 1.year.from_now,
  domain: 'domain.com'
}

cookies.delete(:name, domain: 'domain.com')

The option symbols for setting cookies are:

Constants

CookieOverflow

Raised when storing more than 4K of session data.

GENERATOR_KEY
HTTP_HEADER

Cookies can typically store 4096 bytes.

SECRET_KEY_BASE
SECRET_TOKEN

Public Class Methods

new(app) click to toggle source
# File lib/action_dispatch/middleware/cookies.rb, line 481
def initialize(app)
  @app = app
end

Public Instance Methods

call(env) click to toggle source
# File lib/action_dispatch/middleware/cookies.rb, line 485
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