models.py

from flask_sqlalchemy import SQLAlchemy
from authlib.integrations.sqla_oauth2 import (
    OAuth2ClientMixin,
    OAuth2TokenMixin,
    OAuth2AuthorizationCodeMixin
)

db = SQLAlchemy()


class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(40), unique=True)

    def __str__(self):
        return self.username

    def get_user_id(self):
        return self.id



class OAuth2Client(db.Model, OAuth2ClientMixin):
    __tablename__ = 'oauth2_client'

    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(
        db.Integer, db.ForeignKey('user.id', ondelete='CASCADE'))
    user = db.relationship('User')


class OAuth2AuthorizationCode(db.Model, OAuth2AuthorizationCodeMixin):
    __tablename__ = 'oauth2_code'

    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(
        db.Integer, db.ForeignKey('user.id', ondelete='CASCADE'))
    user = db.relationship('User')


class OAuth2Token(db.Model, OAuth2TokenMixin):
    __tablename__ = 'oauth2_token'

    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(
        db.Integer, db.ForeignKey('user.id', ondelete='CASCADE'))
    user = db.relationship('User')