Yandex Pay Web SDK integration

<script src="https://pay.yandex.ru/sdk/v1/pay.js" onload="onYaPayLoad()" async></script>

function onYaPayLoad() {
    const YaPay = window.YaPay;

    // Payment details
    const paymentData = {
        // For debugging, you need to explicitly specify the `SANDBOX` environment.
        // For the production environment, you can omit this parameter or specify `PRODUCTION`.
        env: YaPay.PaymentEnv.Sandbox,

        // Version 2 specifies the payment type using a token
        // Yandex Pay provides the payment token and the merchant uses it to accept the payment
        version: 2,

        // Codes of your payment currency and country of business
        countryCode: YaPay.CountryCode.Ru,
        currencyCode: YaPay.CurrencyCode.Rub,

        // Merchant data:
        //   -id: The ID that the merchant receives when they register in Yandex Pay.
        //   - name: Merchant name
        //   - url: Merchant website URL
        merchant: {
            id: '<YOUR_MERCHANT_ID>',
            name: 'test-merchant-name',
            url: 'https://test-merchant-url.ru',
        },

        // Data about items and payment amount
        order: {
            // Order ID
            id: 'order-id',
            // Total cost of items
            total: { amount: '43980.00' },
            // Payment items itemization (optional)
            items: [
                { label: 'Yandex Station, black', amount: '26990.00' },
                { label: 'Yandex Station 2, antracite', amount: '16990.00' },
            ],
        },

        // Details of available payment methods
        // (the example uses values for the test environment)
        paymentMethods: [
            {
                type: YaPay.PaymentMethodType.Card,
                gateway: 'test-gateway',
                gatewayMerchantId: 'test-gateway-merchant-id',
                allowedAuthMethods: [YaPay.AllowedAuthMethod.PanOnly],
                allowedCardNetworks: [
                    YaPay.AllowedCardNetwork.Visa,
                    YaPay.AllowedCardNetwork.Mastercard,
                    YaPay.AllowedCardNetwork.Mir,
                    YaPay.AllowedCardNetwork.Maestro,
                    YaPay.AllowedCardNetwork.VisaElectron,
                ],
            },
        ],
    };

    // Handler to obtain a payment token
    function onPaymentProcess(event) {
        // Payment token.
        console.log(`Payment token — ${event.token}`);

        // ...accepting the payment using the payment token...
    }

    // Payment error handler
    function onPaymentError(event) {
        // Show a message that the payment method is unavailable at the moment
        // and suggest the user to try another method.
        console.log('Payment error — ' + event.reason);
    }

    // Payment cancellation handler
    function onPaymentAbort(event) {
        // The user closed the Yandex Pay form.
        // Suggest the user to try another payment method.
    }

    // Create a payment session
    YaPay.createSession(paymentData, {
        onProcess: onPaymentProcess,
        onAbort: onPaymentAbort,
        onError: onPaymentError,
    })
        .then(function (paymentSession) {
            // Show the Yandex Pay button on the page.
            paymentSession.mountButton(document.querySelector('#button_container'), {
                type: YaPay.ButtonType.Pay,
                theme: YaPay.ButtonTheme.Black,
                width: YaPay.ButtonWidth.Auto,
            });
        })
        .catch(function (err) {
            // Couldn't create a payment session. 
        });
}