Question

我想使用session将变量从函数传递到Flask应用中的类。这是我的代码：

@app.route('/login', methods=['POST'])
def login():
    if not request.is_json:
        return jsonify({"msg": "Missing JSON in request"}), 400

    username = request.json.get('username', None)
    password = request.json.get('password', None)
    session['client_fname'] = request.json.get('Client First Name', None)
    session['client_lname'] = request.json.get('Client Last Name', None)

    ... ...

    access_token = create_access_token(identity=username)
    return jsonify(access_token=access_token), 200

class PrivateResource(Resource):
    @app.route('/protected', methods=['GET'])
    @jwt_required

    def sendData():
        return mysqldb.addUser("{}".format(session['client_fname']),"{}".format(session['client_lname']))

我要传递的变量是session['client_fname']和session['client_lname']。但是，当我尝试使用sendData()触发curl -X GET http://localhost:5000/protected -H "Authorization: Bearer JWTGOESHERE"时，我得到：

  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/app.py", line 2309, in __call__
    return self.wsgi_app(environ, start_response)
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/app.py", line 2295, in wsgi_app
    response = self.handle_exception(e)
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask_restful/__init__.py", line 273, in error_router
    return original_handler(e)
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/app.py", line 1741, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/app.py", line 2292, in wsgi_app
    response = self.full_dispatch_request()
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/app.py", line 1815, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask_restful/__init__.py", line 273, in error_router
    return original_handler(e)
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/app.py", line 1718, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/app.py", line 1813, in full_dispatch_request
    rv = self.dispatch_request()
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/app.py", line 1799, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask_jwt_extended/view_decorators.py", line 101, in wrapper
    return fn(*args, **kwargs)
  File "/Users/open/PycharmProjects/FlaskMiddleware/Flask-API-Middleware-V1/authenticate.py", line 48, in sendData
    return mysqldb.addUser("{}".format(session['client_fname'],None),"{}".format(session['client_lname']))
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/werkzeug/local.py", line 377, in <lambda>
    __getitem__ = lambda x, i: x._get_current_object()[i]
  File "/Users/open/venv/FlaskMiddleware/lib/python2.7/site-packages/flask/sessions.py", line 83, in __getitem__
    return super(SecureCookieSession, self).__getitem__(key)
KeyError: 'client_fname'

我使用session传递变量的方式有什么问题？我该如何解决这个问题？

更新

如果这是一个与保存会话有关的cookie问题，我该如何实现？现在，我在curl -H "Content-Type: application/json" -X POST -d '{"username":"user1","password":"abc123","Client First Name":"SAUR","Client Last Name":"KRIS"}' http://localhost:5000/login -c cookies.txt中创建一个Cookie文件，然后尝试curl -X GET http://localhost:5000/protected -H "Authorization: Bearer JWTGOESHERE" -b cookies.txt。现在我得到TypeError: The view function did not return a valid response. The function either returned None or ended without a return statement.，我不确定这是进展还是只是完全错误。

Answer 1

您几乎肯定不会在请求之间保留状态。如果您使用postman或curl，请确保保存会话ID cookie。如果您使用requests，请使用requests.session()。

Answer 2

您的更新看起来可能会有进展，但mysqldb.addUser函数可能返回None。

确定您是否正在取得进展的最简单方法是使用第ini_set('max_execution_time', 0);行的断点进行调试（我通常使用PyCharm，但大多数IDE都会有调试的东西，或者您可以使用pdb）。一个更快但更麻烦的选项，在调用mysqldb.addUser之前添加一个print语句，然后在打印返回值之后添加另一个print语句。

Answer 3

您似乎正在使用flask_jwt_extended，因此您可以通过将数据直接存储在令牌中来绕过问题。

# ...
access_token = create_access_token({
  'first_name': request.json.get('Client First Name', None),
  'last_name': request.json.get('Client Last Name', None)
})

然后在protected路线中检索它：

# ...
user_adata = get_jwt_identity()

在Flask中使用会话传递变量时的键错误

3 个答案: