Sequelize get values from belongsTo relationship - mysql

Question

I am creating an app using an existing database in Mysql.
I can retrieve the values from the tables, but when I try to retrieve the values from associate models, doesn't work.
Purchase Order model:
"use strict";
module.exports = (sequelize, DataTypes) => {
var PurchaseOrder = sequelize.define('purchase_orders' , {
id: {
type: DataTypes.INTEGER(11),
allowNull: false,
primaryKey: true,
autoIncrement: true,
field: 'id'
},
purchaseDate: {
type: DataTypes.DATE,
allowNull: true,
field: 'purchase_date'
},
supplierId: {
type: DataTypes.INTEGER(11),
allowNull: true,
// references: {
// model: 'suppliers',
// key: 'id'
// },
field: 'supplier_id'
},
requestedById: {
type: DataTypes.INTEGER(11),
allowNull: true,
field: 'requested_by_id'
},
masterPurchaseOrderId: {
type: DataTypes.INTEGER(11),
allowNull: true,
// references: {
// model: 'master_purchase_orders',
// key: 'id'
// },
field: 'master_purchase_order_id'
},
createdAt: {
type: DataTypes.DATE,
allowNull: false,
field: 'created_at'
},
updatedAt: {
type: DataTypes.DATE,
allowNull: false,
field: 'updated_at'
}
},{
classMethods:{
associate: (models) => {
PurchaseOrder.belongsTo(models.masterPurchaseOrders,{
foreignkey: 'master_purchase_order_id'
});
},
associate: (models) => {
PurchaseOrder.belongsTo(models.supplier,{
foreignkey: 'supplier_id'
});
},
},
}, {
timestamps: true,
paranoid: false,
underscored: true,
freezeTableName: true,
tableName: 'purchase_orders'
});
return PurchaseOrder;
}
Purchase Order Controller:
"using strict";
const purchaseOrder = require('../models/').purchase_orders;
const Supplier = require('../models/').supplier;
const Master = require('../models/').masterPurchaseOrders;
module.exports= {
index(req, res) {
purchaseOrder
.findAll({
include:[Supplier, Master]
})
.then((masters) => {
res.status(200).json(masters);
})
.catch((error) => {
res.status(500).json(error);
});
},
create(req, res) {
purchaseOrder
.create(req.body)
.then( master => {
res.status(200).json(master);
})
.catch( error => {
res.status(500).json(error);
});
},
};
If I only include the model supplier in the function findall(). I get the data from the purchase and the data from the supplier.
But when I include the model master purchase order. I get an empty json.

Answer 1

Can you do the following
purchaseOrder
.findAll({
include:[{model: Supplier, required:true}, {model: Master, required : false}]
})

Answer 2

It's because you overwrite the associate property of your classMethods, and only the second associate() function will be executed.
You should move both of your association definitions into one function:
classMethods:{
associate: (models) => {
PurchaseOrder.belongsTo(models.masterPurchaseOrders,{
foreignkey: 'master_purchase_order_id'
});
PurchaseOrder.belongsTo(models.supplier,{
foreignkey: 'supplier_id'
});
},
},