Express Js - Sequelize ORM - Many to Many - findOrCreate - not found add, get and set methods

Question

Would be great if someone can help on this.

Already I have gone though How to implement many to many association in sequelize. Still I have question

I'm using Postgre and Express.

I have models size, item and itemsize. Refer below code.

objects are synced to db as expected. when I'm trying to add item and itemsize, I couldn't find the methods item.addxxx(), item.getxxx(), item.setxxx().

here i'm refer the item from

.then((data) => { var item = data[0]; var created = data[1];

as mentioned in https://sequelize.org/master/class/lib/associations/belongs-to-many.js~BelongsToMany.html

size.ts

export const sizeModel = db.define<sizeInstance>("size", {
  id: {
    type: DataTypes.INTEGER,
    autoIncrement: true,
    primaryKey: true,
    allowNull: false,
  },
  title: {
    type: DataTypes.STRING,
    unique: "uk_size_title"
  },
  description: {
    type: DataTypes.STRING,
  },
  isActiveRecord: {
    type: DataTypes.BOOLEAN,
  },
},
  {
    underscored: false
  }
);

item.ts

export const itemModel = db.define(
  "item",
  {
    id: {
      type: DataTypes.INTEGER,
      autoIncrement: true,
      primaryKey: true,
      allowNull: false,
    },
    title: {
      type: DataTypes.STRING,
      validate: {
        len: [3, 15]
      }
    },
    description: {
      type: DataTypes.STRING,
    },
    categoryId: {
      type: DataTypes.INTEGER,
      allowNull: false,
    },
    isActiveRecord: {
      type: DataTypes.BOOLEAN,
      defaultValue: true
    },
  },
  {
    indexes: [
      {
        unique: true,
        fields: ["title", "categoryId"],
      },
    ],
    underscored: false
  }
);

categoryModel.hasMany(itemModel, {
  foreignKey: "categoryId",
});

//define the belongsTo association in the same file that you set the hasMany or the hasOne association.
itemModel.belongsTo(categoryModel, {
  foreignKey: "categoryId",
});

Also I have itemsize.ts

export const itemsizeModel = db.define(
  "itemsize",
  {
    id: {
      type: DataTypes.INTEGER,
      autoIncrement: true,
      primaryKey: true,
      allowNull: false,
    },
    isActiveRecord: {
      type: DataTypes.BOOLEAN,
    },
  },
  {
    timestamps: false,
    underscored: false
  }
);

itemModel.belongsToMany(sizeModel, {
  through: itemsizeModel,
  foreignKey: 'item_itemId'
});

sizeModel.belongsToMany(itemModel, {
  through: itemsizeModel,
  foreignKey: 'size_sizeId'
});

itemcontroller.ts

await itemModel
    .findOrCreate({
      where: {
        title: title,
        categoryId: categoryId
      },
      defaults: {
        title: title,
        description: description,
        categoryId: categoryId,
        isActiveRecord: isActiveRecord,
      },
    })
    .then((data) => {
      var item = data[0];
      var created = data[1];

      if (created) {
        Logger.info(
          `Method: ${methodName}. Item '${title}' created successfully`
        );
        return res.status(200).json(item);
      } else {
        Logger.error(
          `Method: ${methodName}. Item '${title}' already exists`
        );
        return res
          .status(400)
          .json({ message: `Item '${title}' already exists` });
      }
    })
    .catch((err) => {
      Logger.error(
        `Method: ${methodName}. Failed to create item. Exception: ${err}`
      );
      return res.status(400).json(err);
    });