SaaS Monetization & Stripe Integration: Subscription Management & Billing

// Express Webhook server with signature verification
import express from 'express';
import Stripe from 'stripe';

const stripe = new Stripe(process.env.STRIPE_SECRET_KEY!);
const app = express();

app.post('/api/webhooks/stripe', express.raw({ type: 'application/json' }), async (req, res) => {
  const sig = req.headers['stripe-signature']!;
  let event: Stripe.Event;

  try {
    event = stripe.webhooks.constructEvent(req.body, sig, process.env.STRIPE_WEBHOOK_SECRET!);
  } catch (err: any) {
    return res.status(400).send(`Webhook Error: ${err.message}`);
  }

  switch (event.type) {
    case 'invoice.payment_succeeded':
      await handleInvoicePaid(event.data.object as Stripe.Invoice);
      break;
    case 'customer.subscription.deleted':
      await handleSubscriptionCanceled(event.data.object as Stripe.Subscription);
      break;
  }

  res.json({ received: true });
});