sessions.py 文件源码

def open_session(self, app, request):
        sid = request.cookies.get(app.session_cookie_name)
        if not sid:
            sid = self._generate_sid()
            return self.session_class(sid=sid, permanent=self.permanent)
        if self.use_signer:
            signer = self._get_signer(app)
            if signer is None:
                return None
            try:
                sid_as_bytes = signer.unsign(sid)
                sid = sid_as_bytes.decode()
            except BadSignature:
                sid = self._generate_sid()
                return self.session_class(sid=sid, permanent=self.permanent)

        store_id = self.key_prefix + sid
        document = self.store.find_one({'id': store_id})
        if document:
            expiration = document.get('expiration')
            if expiration and expiration <= datetime.utcnow():
                # Delete expired session
                self.store.remove({'id': store_id})
                document = None
        if document is not None:
            try:
                val = document['val']
                data = self.serializer.loads(want_bytes(val))
                return self.session_class(data, sid=sid)
            except:
                return self.session_class(sid=sid, permanent=self.permanent)
        return self.session_class(sid=sid, permanent=self.permanent)