Sequelize n:m association join table with attributes - mysql

Question

I am trying to build the models for a n:m association in Node JS using Sequelize.
The image who follows shows what I am trying to map in the backend:
Using the official documentation, the models that I have defined are the following:
let Dashboards = sequelize.define('Dashboards', {
name: DataType.STRING(30),
category: DataType.TINYINT(2)
}, {
freezeTableName: true,
timestamps: false,
tableName: 'dashboards'
});
Dashboards.associate = function (models) {
Dashboards.belongsToMany(models.Charts, {
through: {
unique: false,
model: models.DashboardCharts
},
foreignKey: 'dashboardId'
});
};
let Charts = sequelize.define('Charts', {
type: DataType.INTEGER(5),
title: DataType.STRING(30),
}, {
freezeTableName: true,
timestamps: false,
tableName: 'charts'
});
Charts.associate = function (models) {
Charts.belongsToMany(models.Dashboards, {
through: {
unique: false,
model: models.DashboardCharts,
},
foreignKey: 'chartId'
});
};
let DashboardCharts = sequelize.define('DashboardCharts', {
title: {
type: DataType.STRING(30)
},
color: {
type: DataType.STRING(7)
}
}, {
freezeTableName: true,
timestamps: false,
tableName: 'dashboard_charts'
});
Now, if using DashboardCharts I try to join the table with Dashboards in this way:
DashboardCharts.findAll({
include: [
{
model: Dashboard,
required: true,
}
]
})
I got this error: SequelizeEagerLoadingError: Dashboards is not associated to DashboardCharts!
What am I doing wrong? Thanks to anyone who could help me!

Answer 1

I found the solution: I was wrong doing the association. With the current configuration, I could only ask for Dashboard's charts or vice versa. The right solution is to set belongsTo from the join table, as it follows:
let Dashboards = sequelize.define('Dashboards', {
name: DataType.STRING(30),
category: DataType.TINYINT(2)
}, {
freezeTableName: true,
timestamps: false,
tableName: 'dashboards'
});
let Charts = sequelize.define('Charts', {
type: DataType.INTEGER(5),
title: DataType.STRING(30),
}, {
freezeTableName: true,
timestamps: false,
tableName: 'charts'
});
let DashboardCharts = sequelize.define('DashboardCharts', {
dashboard_id: {
type: DataType.INTEGER(5),
primaryKey: true
},
chart_id: {
type: DataType.INTEGER(5),
primaryKey: true
},
title: {
type: DataType.STRING(30)
},
color: {
type: DataType.STRING(7)
}
}, {
freezeTableName: true,
timestamps: false,
tableName: 'dashboard_charts'
});
DashboardCharts.associate = function (models) {
DashboardCharts.belongsTo(models.Dashboards, {
foreignKey: 'dashboard_id',
sourceKey: models.Dashboards.id
});
DashboardCharts.belongsTo(models.Charts, {
foreignKey: 'chart_id',
sourceKey: models.Charts.id
});
};