django1/django/contrib/messages/storage/session.py

50 lines
1.8 KiB
Python

import json
from django.conf import settings
from django.contrib.messages.storage.base import BaseStorage
from django.contrib.messages.storage.cookie import (
MessageDecoder, MessageEncoder,
)
from django.utils import six
class SessionStorage(BaseStorage):
"""
Stores messages in the session (that is, django.contrib.sessions).
"""
session_key = '_messages'
def __init__(self, request, *args, **kwargs):
assert hasattr(request, 'session'), "The session-based temporary "\
"message storage requires session middleware to be installed, "\
"and come before the message middleware in the "\
"MIDDLEWARE%s list." % ("_CLASSES" if settings.MIDDLEWARE is None else "")
super(SessionStorage, self).__init__(request, *args, **kwargs)
def _get(self, *args, **kwargs):
"""
Retrieves a list of messages from the request's session. This storage
always stores everything it is given, so return True for the
all_retrieved flag.
"""
return self.deserialize_messages(self.request.session.get(self.session_key)), True
def _store(self, messages, response, *args, **kwargs):
"""
Stores a list of messages to the request's session.
"""
if messages:
self.request.session[self.session_key] = self.serialize_messages(messages)
else:
self.request.session.pop(self.session_key, None)
return []
def serialize_messages(self, messages):
encoder = MessageEncoder(separators=(',', ':'))
return encoder.encode(messages)
def deserialize_messages(self, data):
if data and isinstance(data, six.string_types):
return json.loads(data, cls=MessageDecoder)
return data