Error retrieving values from sequelize association

Question

I need to retrieve the values from two associated models from an existing database.

Model Master

"use strict";

module.exports = (sequelize, DataTypes) => {
  var MasterPurchaseOrder = sequelize.define('master_purchase_order' , {
    id: {
    type: DataTypes.INTEGER(11),
    allowNull: false,
    primaryKey: true,
    autoIncrement: true,
    field: 'id'
  },
  requestedById: {
    type: DataTypes.INTEGER(11),
    allowNull: true,
    field: 'requested_by_id'
  },
  status: {
    type: DataTypes.STRING,
    allowNull: true,
    field: 'status'
  }
},{
  classMethods:{
    associate: (models) =>{
      MasterPurchaseOrder.hasMany(models.purchase_order,{
        as: 'purchase_order',
        foreignkey: 'master_purchase_order_id'
      });
    },
  },
}, {
    timestamps: true,
    paranoid: false,
    underscored: true,
    freezeTableName: true,
    tableName: 'master_purchase_orders'
  });

  return MasterPurchaseOrder;
}

Purchase Order Model

"use strict";

module.exports = (sequelize, DataTypes) => {
  var PurchaseOrder = sequelize.define('purchase_order' , {
    id: {
    type: DataTypes.INTEGER(11),
    allowNull: false,
    primaryKey: true,
    autoIncrement: true,
    field: 'id'
  },
  purchaseDate: {
    type: DataTypes.DATE,
    allowNull: true,
    field: 'purchase_date'
  },
  requestedById: {
    type: DataTypes.INTEGER(11),
    allowNull: true,
    field: 'requested_by_id'
  },
  masterPurchaseOrderId: {
    type: DataTypes.INTEGER(11),
    allowNull: true,
    field: 'master_purchase_order_id'
  }
 },{
  classMethods:{
    associate: (models) => {
      PurchaseOrder.belongsTo(models.master_purchase_order,{
        as: 'master_purchase_order',
        foreignkey: 'master_purchase_order_id'
      });
    },
  },
}, {
    timestamps: true,
    paranoid: false,
    underscored: true,
    freezeTableName: true,
    tableName: 'purchase_orders'
  });

  return PurchaseOrder;
}

This is my purchase order controller:

"using strict";
const purchaseOrder = require('../models/').purchase_order;
const MasterPurchaseOrder = require('../models/').master_purchase_order;

module.exports= {
  index(req, res) {
    purchaseOrder
      .findAll({
        include:[
        {model: MasterPurchaseOrder, as: 'master_purchase_order'}
      ]
      })
      .then((masters) => {
        res.status(200).json(masters);
      });
//      .catch((error) => {
//        res.status(500).json(error);
//      });
  },

};

I get the error:

Unhandled rejection Error: master_purchase_order (master_purchase_order) is not associated to purchase_order!

Any advice

Answer 1

I was overriding the classMethods definition in my child-model.

{
  classMethods:{
    associate: (models) => {
      PurchaseOrder.belongsTo(models.master_purchase_order,{
        as: 'master_purchase_order',
        foreignkey: 'master_purchase_order_id'
      });
      associate: (models) => {
      PurchaseOrder.belongsTo(models.suuplier,{
        as: 'supplier',
        foreignkey: 'supplier_id'
      });
    },
  },
}

The right way is:

{
  classMethods:{
    associate: (models) => {
      PurchaseOrder.belongsTo(models.master_purchase_order,{
        as: 'master_purchase_order',
        foreignkey: 'master_purchase_order_id'
      });
      PurchaseOrder.belongsTo(models.suuplier,{
        as: 'supplier',
        foreignkey: 'supplier_id'
      });
  },
}