1 from django.contrib.messages.storage.base import BaseStorage

     2 

     3 

     4 class SessionStorage(BaseStorage):

     5     """

     6     Stores messages in the session (that is, django.contrib.sessions).

     7     """

     8     session_key = '_messages'

     9 

    10     def __init__(self, request, *args, **kwargs):

    11         assert hasattr(request, 'session'), "The session-based temporary "\

    12             "message storage requires session middleware to be installed, "\

    13             "and come before the message middleware in the "\

    14             "MIDDLEWARE_CLASSES list."

    15         super(SessionStorage, self).__init__(request, *args, **kwargs)

    16 

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

    18         """

    19         Retrieves a list of messages from the request's session.  This storage

    20         always stores everything it is given, so return True for the

    21         all_retrieved flag.

    22         """

    23         return self.request.session.get(self.session_key), True

    24 

    25     def _store(self, messages, response, *args, **kwargs):

    26         """

    27         Stores a list of messages to the request's session.

    28         """

    29         if messages:

    30             self.request.session[self.session_key] = messages

    31         else:

    32             self.request.session.pop(self.session_key, None)

    33         return []