Index: django/contrib/sessions/context_processors.py =================================================================== --- django/contrib/sessions/context_processors.py (revision 0) +++ django/contrib/sessions/context_processors.py (revision 0) @@ -0,0 +1,7 @@ +def visitor_messages(request): + """ + Returns any messages in the session's message queue. + """ + return { + 'visitor_messages': request.session.get_and_delete_messages(), + } Index: django/contrib/sessions/tests.py =================================================================== --- django/contrib/sessions/tests.py (revision 6373) +++ django/contrib/sessions/tests.py (working copy) @@ -14,6 +14,19 @@ 'dog' >>> db_session.pop('some key', 'does not exist') 'does not exist' +>>> db_session.get_messages() +[] +>>> db_session.create_message('first post') +>>> db_session.get_messages() +['first post'] +>>> db_session.get_and_delete_messages() +['first post'] +>>> db_session.get_and_delete_messages() +[] +>>> db_session.create_message('hello') +>>> db_session.create_message('world') +>>> db_session.get_and_delete_messages() +['hello', 'world'] >>> db_session.save() >>> db_session.exists(db_session.session_key) True @@ -31,6 +44,19 @@ 'dog' >>> file_session.pop('some key', 'does not exist') 'does not exist' +>>> file_session.get_messages() +[] +>>> file_session.create_message('first post') +>>> file_session.get_messages() +['first post'] +>>> file_session.get_and_delete_messages() +['first post'] +>>> file_session.get_and_delete_messages() +[] +>>> file_session.create_message('hello') +>>> file_session.create_message('world') +>>> file_session.get_and_delete_messages() +['hello', 'world'] >>> file_session.save() >>> file_session.exists(file_session.session_key) True @@ -48,6 +74,19 @@ 'dog' >>> cache_session.pop('some key', 'does not exist') 'does not exist' +>>> cache_session.get_messages() +[] +>>> cache_session.create_message('first post') +>>> cache_session.get_messages() +['first post'] +>>> cache_session.get_and_delete_messages() +['first post'] +>>> cache_session.get_and_delete_messages() +[] +>>> cache_session.create_message('hello') +>>> cache_session.create_message('world') +>>> cache_session.get_and_delete_messages() +['hello', 'world'] >>> cache_session.save() >>> cache_session.delete(cache_session.session_key) >>> cache_session.exists(cache_session.session_key) Index: django/contrib/sessions/backends/base.py =================================================================== --- django/contrib/sessions/backends/base.py (revision 6373) +++ django/contrib/sessions/backends/base.py (working copy) @@ -18,7 +18,8 @@ """ TEST_COOKIE_NAME = 'testcookie' - TEST_COOKIE_VALUE = 'worked' + TEST_COOKIE_VALUE = 'worked' + MESSAGES_NAME = '_messages' def __init__(self, session_key=None): self._session_key = session_key @@ -59,7 +60,21 @@ def delete_test_cookie(self): del self[self.TEST_COOKIE_NAME] - + + def get_messages(self): + return self.get(self.MESSAGES_NAME, []) + + def get_and_delete_messages(self): + return self.pop(self.MESSAGES_NAME, []) + + def create_message(self, message): + messages = self.get(self.MESSAGES_NAME) + if messages is None: + messages = [] + self[self.MESSAGES_NAME] = messages + messages.append(message) + self.modified = True + def encode(self, session_dict): "Returns the given session dictionary pickled and encoded as a string." pickled = pickle.dumps(session_dict, pickle.HIGHEST_PROTOCOL) Index: docs/sessions.txt =================================================================== --- docs/sessions.txt (revision 6373) +++ docs/sessions.txt (working copy) @@ -190,6 +190,57 @@ return HttpResponse("Please enable cookies and try again.") request.session.set_test_cookie() return render_to_response('foo/login_form.html') + +Visitor Messages +================ + +**New in Django development version** + +The session message system provides a simple way to queue messages for +all (anonymous or authenticated) site visitors. To associate messages with users +in the user database, use the `authentication message framework`_. + +.. _authentication message framework: ../authentication/#messages + +Messages are associated with a session, therefore a message only lasts as long +as a session is valid (see `browser-length sessions vs. persistent sessions`_). + +The message system relies on the session middleware and is accessed via +``request.session``. The API is simple: + + * To create a new message, use + ``request.session.create_message(message='message text').`` + + * To retreive the messages, use ``request.session.get_messages()``, + which returns a list of any messages (strings) in the session's queue. + + * To retrieve and delete messages, use + ``user_obj.get_and_delete_messages()``, which returns the list of any + messages in the session's queue and then deletes the messages from the + queue. + +django.contrib.sessions.context_processors.visitor_messages +----------------------------------------------------------- + +This `context processor`_ is provided (but not installed by default) which makes +these messages available to the template context as the template variable +``{{ visitor_messages }}`` when you use ``RequestContext``. + +.. _context processor: ../templates_python/#subclassing-context-requestcontext + +Here's an example of template code that displays messages:: + + {% if visitor_messages %} + + {% endif %} + +Note that when this context processor is accessed by ``RequestContext``, +``get_and_delete_messages`` is called behind the scenes, so any messages will +be deleted even if you don't display them. Using sessions out of views =========================== Index: docs/authentication.txt =================================================================== --- docs/authentication.txt (revision 6373) +++ docs/authentication.txt (working copy) @@ -947,7 +947,7 @@ Finally, note that this messages framework only works with users in the user database. To send messages to anonymous users, use the `session framework`_. -.. _session framework: ../sessions/ +.. _session framework: ../sessions/#visitor-messages Other authentication sources ============================