https://inbag.ua/js/ecommerce/ecommerce_ga4.js

1function event_cart(event, productData, quantity = 1) {
2    dataLayer.push({ ecommerce: null });
3    dataLayer.push({
4        event: event,
5        ecommerce: {
6            items: [{
7                item_name: productData['name'],
8                item_id: productData['id'],
9                price: productData['price'],
10                item_brand: productData['brand_name'],
11                item_category: productData['category_name'],
12                quantity: quantity
13            }]
14        }
15    });
16    console.log(dataLayer);
17}
18
19function purchase(ecommerceData) {
20    let items = [];
21    $.each(ecommerceData['items'], function (key, productData) {
22        let item = {
23            item_name: productData['name'],
24            item_id: productData['id'],
25            price: productData['price'],
26            item_brand: productData['brand_name'],
27            item_category: productData['category_name'],
28            quantity: productData['quantity'],
29        }
30        items.push(item);
31    });
32    dataLayer.push({ ecommerce: null });
33    dataLayer.push({
34        event: "purchase",
35        ecommerce: {
36            transaction_id: ecommerceData['number'],
37            affiliation: ecommerceData['affiliation'],
38            value: ecommerceData['total'],
39            tax: "0",
40            shipping: "0",
41            currency: "UAH",
42            items: items
43        }
44    });
45    console.log(dataLayer);
46}