woocommerce-paypal-payments/modules.local/ppcp-button/resources/js/modules/CartConfig.js

class CartConfig {

    constructor(config, errorHandler) {
        this.config = config;
        this.errorHandler = errorHandler;
    }

    configuration() {

        const createOrder = (data, actions) => {
            return fetch(this.config.ajax.create_order.endpoint, {
                method: 'POST',
                body: JSON.stringify({
                    nonce: this.config.ajax.create_order.nonce,
                    purchase_units:[]
                })
            }).then(function (res) {
                return res.json();
            }).then(function (data) {
                if (!data.success) {
                    //Todo: Error handling
                    return;
                }
                return data.data.id;
            });
        }
        const onApprove = (data, actions) => {
            return actions.redirect(this.config.redirect);
        }
        return {
            createOrder,
            onApprove,
            onError: (error) => {
                this.errorHandler.message(error);
            }
        }
    }
}

export default CartConfig;