在 flask-sqlalchemy 中向用户表添加注释关系时遇到问题

Question

所以我刚刚完成了关于 flask-sqlalchemy 的 python YouTuber Corey Schafers 教程。我在修改我们创建的数据库时遇到问题。我正在尝试与我的评论表和用户表建立关系。当用户发表评论时，我想存储用户名。到目前为止，我似乎无法将用户对帖子的评论与评论作者的姓名联系起来。这是相关的代码。

from datetime import datetime
from itsdangerous import TimedJSONWebSignatureSerializer as Serializer
from smushd_site import db, login_manager
from flask_login import UserMixin
from flask import current_app



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


class User(db.Model,UserMixin):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(20), unique=True, nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False)
    image_file = db.Column(db.String(20), nullable=False, default='default.jpg')
    password = db.Column(db.String(60), nullable=False)
    posts = db.relationship('Post', backref='author', lazy=True)
    #comments_name = db.relationship('Comment', backref='author_comment', lazy=True)

    def get_reset_token(self, expires_sec=1800):
        s = Serializer(current_app.config['SECRET_KEY'], expires_sec)
        return s.dumps({'user_id': self.id}).decode('utf-8')

    @staticmethod
    def verify_reset_token(token):
        s = Serializer(current_app.config['SECRET_KEY'])
        try:
            user_id = s.loads(token)['user_id']
        except:
            return None
        return User.query.get(user_id)



    def __repr__(self):
        return f"User('{self.username}', '{self.email}', '{self.image_file}')"


class Post(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(100), nullable=False)
    date_posted = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
    content = db.Column(db.Text, nullable=False)
    user_id = db.Column(db.Integer, db.ForeignKey('user.id'), nullable=False)
    comments = db.relationship('Comment', backref='author', lazy=True)

    def __repr__(self):
        return f"Post('{self.title}', '{self.date_posted}')"



class Comment(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    body = db.Column(db.String(100), nullable=False)
    name = db.Column(db.String(100), nullable=False,default="stalin")
    timestamp = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
    #poster_id = db.Column(db.String(100), db.ForeignKey('poster.id'), nullable=False)
    post_id = db.Column(db.Integer, db.ForeignKey('post.id'), nullable=False)
    #comment_name = db.Column(db.String(100), nullable=False)
    #username = db.Column(db.String(100), db.ForeignKey('user.id'), nullable=False)
    #comment_name = db.relationship('User', backref='author', lazy=True)

    def __repr__(self):
        return f"Comment('{self.body}', '{self.timestamp}')"

这些是包含代码和 youtube 系列的 repo 的链接： https://github.com/CoreyMSchafer/code_snippets/blob/master/Python/Flask_Blog/12-Error-Pages/flaskblog/models.py https://www.youtube.com/watch?v=cYWiDiIUxQc&list=PL-osiE80TeTs4UjLw5MM6OjgkjFeUxCYH&index=4

Answer 1

这是我写的代码；它可能会帮助你。 Feedback 只是一个例子 - 你可以用 Comment 做同样的事情。

class User(db.Model, UserMixin):
    __bind_key__ = 'user'
    id = db.Column(db.Integer, primary_key=True) 
    username = db.Column(db.String(25), unique=True, nullable=False) 
    email = db.Column(db.String(125), unique=True, nullable=False) 
    image_file = db.Column(db.String(20), nullable=False, default='default.jpg') 
    password = db.Column(db.String(65), nullable=False) 
    about = db.Column(db.String(100), nullable=False) 
    posts = db.relationship('Post', backref='author', lazy=True) 
    feedbacks = db.relationship('Feedback', backref='author', lazy=True) 
    create_account = db.Column(db.DateTime, nullable=False, default=datetime.now)
    badges = db.Column(db.DateTime, nullable=False, default=datetime.now)

class Feedback(db.Model):
    __bind_key__ = 'feedback'
    id = db.Column(db.Integer, primary_key=True) 
    content = db.Column(db.Text, nullable=False) 
    date_posted = db.Column(db.DateTime, nullable=False, default=datetime.now)
    user_id = db.Column(db.Integer, db.ForeignKey('user.id'), nullable=False)