It says items is undefined

Question

The code is show below.

const mongoose = require('mongoose');

const Schema = mongoose.Schema;

const user = new Schema({
    name: {
        type: String,
        required: true
    },
    email: {
        type: String,
        required: true
    },
    password: {
        type: String,
        required: true
    },
    resetToken: String,
    resetExpiration: String,
    products: [{type: mongoose.Types.ObjectId, required: true, ref: 'Shop'}],
    cart: {
        items: [
            {
                productId: {type: mongoose.Types.ObjectId, ref: 'Shop', required: true},
                quantity: {type: Number, required: true},
            }
        ]
    },
});

user.methods.addToCart = (product) => {

    const itemIndex = this.cart.items.findIndex(prod => {
        return prod.productId.toString() === product._id.toString();
    });

    let newQuantity = 1;
    const updatedCartItems = [...this.cart.items];

    if(itemIndex >= 0) {
        newQuantity = this.cart.items[itemIndex].quantity + 1;
        updatedCartItems[itemIndex].quantity = newQuantity;
    } else {
        updatedCartItems.push({
            productId: product,
            quantity: newQuantity
        });
    }

    const updatedCart = {
        items: updatedCartItems
    }
    this.cart = updatedCart;
    return this.save();
}

const model = mongoose.model('User', user);

module.exports = model;

I am trying to store product in the cart instance method as per above schema, but when i send product from my controller to addToCart it says items is undefined on this.cart.items. I haven't used instance method much in mongoose so, i don't know this issue is it with schema or general problem.

let me know if you need any other information.

Answer 1

It was a silly mistake, actually i was using arrow function. so it wasn't bind to schema.