cson.py

import cherrypy
import datetime
import time
from cherrys import RedisSession
import json


class RedisJsonSession(RedisSession):

    def __init__(self, *arg, **kwargs):
        RedisSession.__init__(self, *arg, **kwargs)
        self.dirty = False

    def __setitem__(self, key, value):
        if not self.loaded:
            self.load()
        self._data[key] = value
        self.dirty = True

    def __delitem__(self, key):
        if not self.loaded:
            self.load()
        self.dirty = True
        del self._data[key]

    def _load(self):
        cache_data = self.cache.get(self._id)
        if not cache_data:
            return cache_data
        try:
            data = json.loads(cache_data)
        except ValueError:
            return None
        return data['sdata'], datetime.datetime.fromtimestamp(data['setime'])

    def _save(self, expiration_time):
        if self.dirty is True:
            etime = time.mktime(expiration_time.timetuple())
            json_data = json.dumps({'sdata': self._data, 'setime': etime})
            result = self.cache.setex(self.id, json_data, self.timeout * 60)
            if not result:
                raise AssertionError(
                    "Session data for id %r not set." %
                    self.id)
        else:
            pass

    def _delete(self):
        self.cache.delete(self.id)

    def expire_session(self):
        self.cache.delete(self.id)