Question

我正在尝试运行Flask应用程序，但不断出现以下错误：

AttributeError: type object 'User' has no attribute 'get'

我假设它来自我的Models.py代码：

class User(db.Model):
    __tablename__ = 'users'
    __table_args__ = {'extend_existing': True} 
    id = db.Column(db.Integer, primary_key = True)
    email = db.Column(db.String(64), unique=True, index=True)
    username = db.Column(db.String(64), unique=True, index=True)
    password = db.Column(db.String(128))
    confirmed = db.Column(db.Boolean, default=False)
    #posts = db.relationship('Post', lazy='dynamic')


    def is_active(self):
        return True

    def get_id(self):
        return self.email

    def is_authenticated(self):
        return self.authenticated

    def is_anonymous(self):
        return False


    @login_manager.user_loader
    def load_user(userid):

        return User.get(User.id==userid)

玩转之后，看来我可能需要在某个地方插入以下代码块或对它进行修改？

def get_object(self):
    return self.request.user

或某种衍生形式。任何帮助将不胜感激。谢谢！

这是完整的追溯：

 form = PostForm()
[2018-07-06 11:08:23,652] ERROR in app: Exception on /index [GET]
Traceback (most recent call last):
File 
"/Users.../sqlalchemy/sql/elements.py", line 682, in __getattr__
return getattr(self.comparator, key)
AttributeError: 'Comparator' object has no attribute 'request'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/...python3.6/site-packages/flask/app.py", line 2292, in 
wsgi_app
response = self.full_dispatch_request()
File "/Users/...b/python3.6/site-packages/flask/app.py", line 1815, in 
full_dispatch_request
rv = self.handle_user_exception(e)
File "/Users/...python3.6/site-packages/flask/app.py", line 1718, in 
handle_user_exception
reraise(exc_type, exc_value, tb)
File "/Users//python3.6/site-packages/flask/_compat.py", line 35, in 
reraise
raise value
File "/Users/...python3.6/site-packages/flask/app.py", line 1813, in 
full_dispatch_request
rv = self.dispatch_request()
File "/Users/WilliamStevens//site-packages/flask/app.py", line 1799, in 
dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
 File "/Users//Documents/deplorable_snowflake/.../views.py", line 52, in 
index
return render_template('frontpage.html', form=form, posts=posts)
File "/Users/.../python3.6/site-packages/flask/templating.py", line 133, 
   in render_template
  ctx.app.update_template_context(context)
    File "/Users/W/python3.6/site-packages/flask/app.py", line 792, in 
   update_template_context
   context.update(func())
    File "/Users/.../flask_login/utils.py", line 368, in 
   _user_context_processor
   return dict(current_user=_get_user())
  File "/Users/.../python3.6/site-packages/flask_login/utils.py", line 
  335, 
  in _get_user
  current_app.login_manager._load_user()
  File "/Users/.../python3.6/site- 
  packages/flask_login/login_manager.py", 
  line 359, in _load_user
  return self.reload_user()
  File "/Users/.../lib/python3.6/site- 
  packages/flask_login/login_manager.py", line 321, in reload_user
   user = self.user_callback(user_id)
   File 
  "/Users/.../models.py", line 53, in load_user
  return User.get(User.id==userid)
  File 
 "/Users/WilliamStevens/.../models.py", line 47, in get
 return self.request.user
    File "/Users/...site-packages/sqlalchemy/sql/elements.py", line 688, 
  in 
 __getattr__
  key)
 AttributeError: Neither 'BinaryExpression' object nor 'Comparator' 
 object has an attribute 'request'

Answer 1

我只是有这个问题。 shmee提出的解决方案对我有用：

load_user()函数不应成为User类的一部分，而应成为其自己的独立函数。
load_user()函数应调用User.query.get(user_id)，而不是User.get(user_id)。
- 我认为造成这种混乱的原因是，Flask-Login的文档has it the latter way截至今天：return User.get(user_id)。

示例代码：

class User(db.Model, UserMixin):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True, nullable=False)
    password = db.Column(db.String(80))

    def __repr__(self):
        return '<User %r>' % self.username


@login_manager.user_loader
def load_user(user_id):
    return User.query.get(user_id)

Answer 2

谢谢@Nathan Wailes 和@shmee。这些解决方案也解决了我的问题。

@will - 最好为 User 模型继承 UserMixin 类和 db.Model 类，而不是显式编写以下方法的代码：

is_active
is_authenticated
is_anonymous
get_id

class User(UserMixin,db.Modle):
    __tablename__ = 'users'
    __table_args__ = {'extend_existing': True} 
    id = db.Column(db.Integer, primary_key = True)
    email = db.Column(db.String(64), unique=True, index=True)
    username = db.Column(db.String(64), unique=True, index=True)
    password = db.Column(db.String(128))
    confirmed = db.Column(db.Boolean, default=False)

然后在app.py（主应用类）中，可以在调用login、logout等之前添加如下代码，端点：

@login_manager.user_loader
def load_user(userid):
    return User.query.get(userid)

您可以在此处参考 Flask-Login 文档：https://flask-login.readthedocs.io/en/latest/

AttributeError：类型对象“ User”没有属性“ get”

2 个答案: