models.py

新建models.py，将模型定义全部放到这个独立的文件中。

from datetime import datetimefrom werkzeug.security import generate_password_hash,check_password_hash

from exts import db

class User(db.Model):    __tablename__ = 'user'    id = db.Column(db.Integer, primary_key=TabError, autoincrement=True)    username = db.Column(db.String(20), nullable=False)    _password = db.Column(db.String(200), nullable=False) #neibushiyong    nickname = db.Column(db.String(20))    @property    def password(self):        return self._password    @password.setter    def password(self, row_password):        self._password = generate_password_hash(row_password)    def check_password(self, row_password):        result = check_password_hash(self._password, row_password)        return resultclass Question(db.Model):    __tablename__ = 'question'    id = db.Column(db.Integer, primary_key=True, autoincrement=True)    title = db.Column(db.String(100), nullable=False)    detail = db.Column(db.Text, nullable=False)    creat_time = db.Column(db.DateTime, default=datetime.now)    author_id = db.Column(db.Integer, db.ForeignKey('user.id'))    author = db.relationship('User', backref=db.backref('question'))class Comment(db.Model):    __tablename__='comment'    id = db.Column(db.Integer, primary_key=True, autoincrement=True)    author_id = db.Column(db.Integer, db.ForeignKey('user.id'))    question_id = db.Column(db.Integer , db.ForeignKey('question.id'))    creat_time = db.Column(db.DateTime,default=datetime.now)    detail = db.Column(db.Text , nullable=False)    question = db.relationship('Question',backref = db.backref('comments',order_by=creat_time.desc))    author = db.relationship('User',backref = db.backref('comments'))

新建exts.py，将db = SQLAlchemy()的定义放到这个独立的文件中。

from flask_sqlalchemy import SQLAlchemydb = SQLAlchemy()

models.py和主py文件，都从exts.py中导入db。

在主py文件中，对db进行始化，db.init_app(app)。

from models import Question,User,Commentfrom exts import dbapp=Flask(__name__)app.config.from_object(config)db.init_app(app)