KeyError:Flask_security中的“security”?

我正在使用Flask建立一个网站,我现在正在尝试使用 Flask_Security 用于基于令牌的认证。现在我想从用户获取auth_token,为此我使用 get_auth_token() method 。不幸的是,我在这条消息下面看到了堆栈。

有人知道怎么了吗?欢迎提供所有提示!

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1836, in __call__
    return self.wsgi_app(environ, start_response)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1820, in wsgi_app
    response = self.make_response(self.handle_exception(e))
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1403, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1817, in wsgi_app
    response = self.full_dispatch_request()
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1477, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1381, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1475, in full_dispatch_request
    rv = self.dispatch_request()
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1461, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/kramer65/myapp-kram/app/views/apiviews.py", line 33, in api_login
    return jsonify({'token': user.get_auth_token()})
  File "/usr/local/lib/python2.7/dist-packages/flask_security/core.py", line 313, in get_auth_token
    return _security.remember_token_serializer.dumps(data)
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/local.py", line 338, in __getattr__
    return getattr(self._get_current_object(), name)
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/local.py", line 297, in _get_current_object
    return self.__local()
  File "/usr/local/lib/python2.7/dist-packages/flask_security/core.py", line 30, in <lambda>
    _security = LocalProxy(lambda: current_app.extensions['security'])
KeyError: 'security'