Commit e6c55994 authored by Luke Plant's avatar Luke Plant
Browse files

Reduced CookieStorage.max_cookie_size to 75% of 4K to be nice to Internet Explorer 

Internet Explorer, up to at least version 7, allows only 4K cookie data *per
domain*, rather than per cookie, so we ensure that stored messages leave
some room for other cookies.




git-svn-id: http://code.djangoproject.com/svn/django/trunk@12287 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent 63d07258

django/contrib/messages/storage/cookie.py

+6 −2
Original line number Diff line number Diff line 
import hmac



from django.conf import settings

from django.utils.hashcompat import sha_hmac

from django.contrib.messages import constants

from django.contrib.messages.storage.base import BaseStorage, Message

from django.http import CompatCookie

from django.utils import simplejson as json

from django.utils.hashcompat import sha_hmac





class MessageEncoder(json.JSONEncoder):
@@ -46,7 +47,10 @@ class CookieStorage(BaseStorage): 
    Stores messages in a cookie.

    """

    cookie_name = 'messages'

    max_cookie_size = 4096

    # We should be able to store 4K in a cookie, but Internet Explorer

    # imposes 4K as the *total* limit for a domain.  To allow other

    # cookies, we go for 3/4 of 4K.

    max_cookie_size = 3072

    not_finished = '__messagesnotfinished__'



    def _get(self, *args, **kwargs):

django/contrib/messages/tests/cookie.py

+9 −3
Original line number Diff line number Diff line
@@ -69,19 +69,25 @@ class CookieTest(BaseTest): 
        storage = self.get_storage()

        response = self.get_response()



        # When storing as a cookie, the cookie has constant overhead of approx

        # 54 chars, and each message has a constant overhead of about 37 chars

        # and a variable overhead of zero in the best case. We aim for a message

        # size which will fit 4 messages into the cookie, but not 5.

        # See also FallbackTest.test_session_fallback

        msg_size = int((CookieStorage.max_cookie_size - 54) / 4.5 - 37)

        for i in range(5):

            storage.add(constants.INFO, str(i) * 900)

            storage.add(constants.INFO, str(i) * msg_size)

        unstored_messages = storage.update(response)



        cookie_storing = self.stored_messages_count(storage, response)

        self.assertEqual(cookie_storing, 4)



        self.assertEqual(len(unstored_messages), 1)

        self.assert_(unstored_messages[0].message == '0' * 900)

        self.assert_(unstored_messages[0].message == '0' * msg_size)



    def test_json_encoder_decoder(self):

        """

        Tests that an complex nested data structure containing Message

        Tests that a complex nested data structure containing Message

        instances is properly encoded/decoded by the custom JSON

        encoder/decoder classes.

        """

django/contrib/messages/tests/fallback.py

+3 −1
Original line number Diff line number Diff line
@@ -147,8 +147,10 @@ class FallbackTest(BaseTest): 
        storage = self.get_storage()

        response = self.get_response()



        # see comment in CookieText.test_cookie_max_length

        msg_size = int((CookieStorage.max_cookie_size - 54) / 4.5 - 37)

        for i in range(5):

            storage.add(constants.INFO, str(i) * 900)

            storage.add(constants.INFO, str(i) * msg_size)

        storage.update(response)



        cookie_storing = self.stored_cookie_messages_count(storage, response)