发现 Sequelize 循环依赖

Question

I get this weird error when I was trying to sync my database:

Unhandled rejection Error: Cyclic dependency found. roles is dependent of itself.
Dependency chain: roles -> users => roles

I have this following junction table model called Permission

const Permission = db.define('permission', {
    id: {
        type: type.INTEGER,
        primaryKey: true,
        autoIncrement: true
    },
    role_id: {
        type: type.INTEGER,
        references: {
            model: 'roles',
            key: 'id',
        }
    },
    resource_id: {
        type: type.INTEGER,
        references: {
            model: 'resources',
            key: 'id',
        }
    },
});

Why does this error happen? And how can I fix it? In my User model, User has one Role :

const User = db.define('user', {
    id: {
        type: Sequelize.INTEGER,
        primaryKey: true,
        autoIncrement: true
    },
    role_id : {
        type: Sequelize.INTEGER,
        references: {
            model: 'roles',
            key: 'id',
        }
    }
});

User.hasOne(Role)

Edit : Here's my Role model:

const Role = db.define('role', {
    id: {
        type: Sequelize.INTEGER,
        primaryKey: true,
        autoIncrement: true
    },
    name: Sequelize.STRING,
})

module.exports = Role

Answer 1

In sequelize docs it says:

The A.hasOne(B) association means that a One-To-One relationship exists between A and B, with the foreign key being defined in the target model (B)

Which means, User model shouldn't have a foreign key to Role model. Try changing your User model to:

const User = db.define('user', {
    id: {
        type: Sequelize.INTEGER,
        primaryKey: true,
        autoIncrement: true
    }

});

User.hasOne(Role)

And then your Role model to:

const Role = db.define('role', {
    id: {
        type: Sequelize.INTEGER,
        primaryKey: true,
        autoIncrement: true
    },
    name: Sequelize.STRING,
    user_id : {
        type: Sequelize.INTEGER,
        references: {
            model: 'users',
            key: 'id',
        }
    }
 })

Role.belongsTo(User);    

module.exports = Role