get_jwt_identity() 在 Flask-JWT-Extended 中返回 None

Posted 2023-03-10

【中文标题】get_jwt_identity() 在 Flask-JWT-Extended 中返回 None

【英文标题】：get_jwt_identity() returning None in Flask-JWT-Extended

【发布时间】：2019-07-19 10:48:03

【问题描述】：

我正在使用 Flask-JWT-Extended 来保护我的 Flask API。登录后，在受保护的路由（添加用户）中，我调用 get_jwt_identity()，但它返回 None，所以我无法获取身份。

@flask_app.route('/<api_version>/login', methods=['POST'])
def login(api_version):
    print(f'login', request.form)
    response = None
    try:
        username = request.form['username']
        password = request.form['password']

        if not username:
            return jsonify("msg": "Missing username parameter"), 400
        if not password:
            return jsonify("msg": "Missing password parameter"), 400

        user = User.get_with_password(username, password)

        if (not user):
            e1 = Unauthorized(
                'Invalid username or password.  Please try again.')
            e1.status = 401
            raise e1

        """ flask_login.login_user(user, remember=True) """
        access_token = create_access_token(identity=username)
        response = json.dumps("token": access_token, cls=CustomJSONEncoder)
    except Exception as e:
        errMsg = f'Error Logging in user username if username else "": e'
        status = e.status if hasattr(e, 'status') else 500
        print(f'errMsg')
        traceback.print_exc()
        return Response(
            json.dumps("message": errMsg, "status": status, "stack": traceback.format_exc() ), status=status, mimetype='application/json')


    resp = Response(response, status=200, mimetype='application/json')
    return resp

@flask_app.route('/<api_version>/add-user', methods=['POST'])
@jwt_required
def add_user(api_version):
    print(f'add-user', request)
    response = None
    username = None
    password = None
    allow_admin = None
    try:
        data = request.get_json()
        print(f'add-user data', data)

        if 'username' in data:
            username = data['username']
        else:
            return jsonify("msg": "Missing username parameter"), 400
        if 'password' in data:
            password = data['password']
        else:
            return jsonify("msg": "Missing password parameter"), 400
        if 'allow_admin' in data:
            allow_admin = data['allow_admin']

        """ user = User.get_with_password(username, password)"""
        user = get_jwt_identity()
        print('user',user)

        if (not user):
            e1 = Unauthorized(
                'Invalid username or password.  Please try again.')
            e1.status = 401
            raise e1

        response = json.dumps("user": user, cls=CustomJSONEncoder)
    except Exception as e:
        errMsg = f'Error Adding User username: e'
        status = e.status if hasattr(e, 'status') else 500
        print(f'errMsg')
        traceback.print_exc()
        return Response(
            json.dumps("message": errMsg, "status": status, "stack": traceback.format_exc() ), status=status, mimetype='application/json')


    resp = Response(response, status=200, mimetype='application/json')
    return resp

用户.py

class User():
    @classmethod
    def get_with_password(cls, username, password):
        print(f'User get_with_password username with password')
        user_db = account.get_account(username)
        print(f'User returned from DB: user_db')

        user = User()
        if not user_db or not len(user_db) or (not 'password' in user_db):
            return None
        user.username = username
        user.id = username

        if bcrypt.check_password_hash(user_db['password'], password):

            user.role = user_db['role']
            #user.is_authenticated = True
            print(
                f'loginUser returning vars(user) ')
            return user
        return None

【问题讨论】：

登录后尝试打印访问令牌，以及访问受保护功能add_user时，看看它是否可用！如果不是，它应该引发一个丢失的令牌错误，而不是只返回 None！

【参考方案1】：

我也遇到了同样的问题，就我而言，我忘了添加@jwt_required

@jwt_required
def get(self):
    uid = get_jwt_identity()
    print("self.uid",uid)

在你的代码中有@jwt_required，检查可能是令牌已过期

【参考方案2】：

我也遇到了同样的问题，通过以下步骤解决了

第 1 步：检查您是否已将应用 (flask_app) 包装如下。

from flask_jwt_extended import JWTManager
jwt = JWTManager(flask_app)
   

第 2 步：检查您的应用中是否有 JWT_BLACKLIST_ENABLED。

如果您的应用中不存在 JWT_BLACKLIST_ENABLED = False 或 JWT_BLACKLIST_ENABLED，请在您使用过 create_token_method() 的地方添加以下方法（在您的情况下，它是登录方法）。

@jwt.user_claims_loader
def add_claims_to_access_token(identity):
    return 
        'identity': identity
    

如果 JWT_BLACKLIST_ENABLED = True 然后在您的登录方法上方添加以下内容。

@jwt.token_in_blacklist_loader
def check_if_token_in_blacklist(decrypted_token):
    jti = decrypted_token['jti']
    return jti in blacklist