nextjs-stripe-integration

Add Stripe payment processing to Next.js with checkout sessions, subscriptions, and webhooks. Use modern APIs and secure environment loading.

• Implement Stripe payment flows in Next.js projects
• Create checkout sessions and manage subscriptions
• Handle webhooks securely with signature verification
• Use Customer Portal for subscription management

• ✅ Load env vars inside API functions, not at module level
• ❌ DO NOT use `stripe.redirectToCheckout()`
• Critical: Verify webhook signatures with `constructEvent`
• Use `mode: 'payment'` or `mode: 'subscription'` in sessions
• Allow payment routes in auth middleware via `unauthenticatedPaths`
• Customer Portal enables subscription management

1. 1.Install `stripe` and `@stripe/stripe-js`
2. 2.Set environment variables in `.env.local`
3. 3.Create API routes for checkout and webhooks
4. 4.Verify webhook signatures using `constructEvent`
5. 5.Add payment routes to `unauthenticatedPaths` in middleware