digital-store/config/routes/payments/qiwi.payment.js

module.exports = function(server, db, qiwiApi) {
    server.put('/payment', (req, res) => {
        const billId = qiwiApi.generateId();
        const fields = {
            amount: req.body.totalPrice,
            currency: 'RUB',
            comment: `Оплата товара "${req.body.items[0].title}" Счёт: ${billId}`,
            expirationDateTime: qiwiApi.getLifetimeByDay(),
            customFields: {themeCode: 'Sergei-YaS7mIY0CQe'},
            email: req.body.email,
            successUrl: `https://polar-peak-95205.herokuapp.com/success?bill_id=${billId}&item_id=${req.body.items[0].id}&payment=qiwi`
        }
        qiwiApi.createBill(billId, fields).then((data) => {
            res.send(data);
        });
    });
}