SvelteKitSaasBoilerplate/src/routes/checkout/success/+page.ts

import type { PageLoad } from './$types';
import { redirect } from '@sveltejs/kit';
import Stripe from 'stripe';

export const load: PageLoad = async ({fetch}) => {
  const response = await fetch('/api/checkout/status');
	if (!response.ok) {
		console.error('Failed to fetch checkout status');
		return;
	}

	const responseJson = await response.json();
	const checkoutSession: Stripe.Checkout.Session = responseJson.checkoutSession;
	const lineItems: Stripe.LineItem[] = responseJson.lineItems.data;
	const paymentStatus: Stripe.Checkout.Session.PaymentStatus = responseJson.paymentStatus;

	if (paymentStatus == 'unpaid') {
		throw redirect(303, '/checkout/cancelled');
	}

	return {
		checkoutSession,
		lineItems,
		paymentStatus
	};
};