Flask 学习问题记录

1，没有个table设置主键的情况下，却设置了个外键，导致出现DB无发变更。

sqlalchemy.exc.ArgumentError: Mapper Mapper|Content_of_bbs|contents could not assemble any primary key columns for mapped table 'contents'

class User(db.Model):
    __tablename__ = 'user'
    id = db.Column(db.Integer,primary_key = True,autoincrement=True)
    telephone=db.Column(db.String(11),nullable=False)
    username = db.Column(db.String(50), nullable=False)
    password = db.Column(db.String(100), nullable=False)

class Content_of_bbs(db.Model):
    __tablename__='contents'
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)#不设置，会导致错误。。。
    user_id=db.Column(db.Integer,db.ForeignKey('user.id'))
    content=db.Column(db.TEXT())
    time=db.Column(db.DATETIME)

2，装饰器没有返回错误

return wrapper位置不对，导致login_requied没有返回值。出现以下错误：

  File "C:\Python27\lib\site-packages\flask\app.py", line 1011, in add_url_rule
    endpoint = _endpoint_from_view_func(view_func)
  File "C:\Python27\lib\site-packages\flask\helpers.py", line 68, in _endpoint_from_view_func
    assert view_func is not None, 'expected view func if endpoint ' \
AssertionError: expected view func if endpoint is not provided.

def login_requied(func):
    @wraps(func)
    def wrapper(*args,**kwargs):
        if session.get('user_id'):
            return func(*args,**kwargs)
        else:
            return redirect(url_for('login'))
    return wrapper