Flask-SQLAlchemy-default-time-setting-problem

1.遇到的问题

把flask时间 created 设置为UTC时间

class PyLink(db.Model):
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    name = db.Column(db.String(300), nullable=False)
    link = db.Column(db.String(1000), nullable=False)
    avatar = db.Column(db.String(1000), nullable=False)
    brief = db.Column(db.String(1000), nullable=False)
    created = db.Column(db.DateTime, default=datetime.now)

修改添加timezone.utc参数

class PyLink(db.Model):
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    name = db.Column(db.String(300), nullable=False)
    link = db.Column(db.String(1000), nullable=False)
    avatar = db.Column(db.String(1000), nullable=False)
    brief = db.Column(db.String(1000), nullable=False)
    created = db.Column(db.DateTime, default=datetime.now(timezone.utc))

之后的多条数据时间都为Flask的启动时间

2.问题原因

 1.created = db.Column(db.DateTime, default=datetime.now())

2. created = db.Column(db.DateTime, default=datetime.now)

1.中datetime.now()生成一个固定的时间, Flask程序部署的时间，所有的数据都是这个固定时间
2.datetime.now生成当前时间

3.解决办法

class PyLink(db.Model):
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    name = db.Column(db.String(300), nullable=False)
    link = db.Column(db.String(1000), nullable=False)
    avatar = db.Column(db.String(1000), nullable=False)
    brief = db.Column(db.String(1000), nullable=False)
    created = db.Column(db.DateTime, default=datetime.utcnow)

把时间函数修改为datetime.utcnow

参考：Flask sqlalchemy 设置默认时间