import json import uuid from time import time from . import AbstractStorage, Session class MemcachedStorage(AbstractStorage): """Memcached storage""" def __init__(self, memcached_conn, *, cookie_name="AIOHTTP_SESSION", domain=None, max_age=None, path='/', secure=None, httponly=True, key_factory=lambda: uuid.uuid4().hex, encoder=json.dumps, decoder=json.loads): super().__init__(cookie_name=cookie_name, domain=domain, max_age=max_age, path=path, secure=secure, httponly=httponly, encoder=encoder, decoder=decoder) self._key_factory = key_factory self.conn = memcached_conn async def load_session(self, request): cookie = self.load_cookie(request) if cookie is None: return Session(None, data=None, new=True, max_age=self.max_age) else: key = str(cookie) stored_key = (self.cookie_name + '_' + key).encode('utf-8') data = await self.conn.get(stored_key) if data is None: return Session(None, data=None, new=True, max_age=self.max_age) data = data.decode('utf-8') try: data = self._decoder(data) except ValueError: data = None return Session(key, data=data, new=False, max_age=self.max_age) async def save_session(self, request, response, session): key = session.identity if key is None: key = self._key_factory() self.save_cookie(response, key, max_age=session.max_age) else: if session.empty: self.save_cookie(response, '', max_age=session.max_age) else: key = str(key) self.save_cookie(response, key, max_age=session.max_age) data = self._encoder(self._get_session_data(session)) max_age = session.max_age # https://github.com/memcached/memcached/wiki/Programming#expiration # "Expiration times can be set from 0, meaning "never expire", to # 30 days. Any time higher than 30 days is interpreted as a Unix # timestamp date. If you want to expire an object on January 1st of # next year, this is how you do that." if max_age is None: expire = 0 elif max_age > 30*24*60*60: expire = int(time()) + max_age else: expire = max_age stored_key = (self.cookie_name + '_' + key).encode('utf-8') await self.conn.set( stored_key, data.encode('utf-8'), exptime=expire)