Add Next.js App Router webhook example that leverages Route Handlers (#…

…2259)

examples/webhook-signing/nextjs/app/api/webhooks/route.ts

@@ -0,0 +1,69 @@
+import {Stripe} from 'stripe';
+import {NextResponse} from 'next/server';
+import {headers} from 'next/headers';
+
+const stripe = new Stripe(process.env.STRIPE_SECRET_KEY as string);
+
+export async function POST(req: Request) {
+  let event: Stripe.Event;
+
+  try {
+    const stripeSignature = (await headers()).get('stripe-signature');
+
+    event = stripe.webhooks.constructEvent(
+      await req.text(),
+      stripeSignature as string,
+      process.env.STRIPE_WEBHOOK_SECRET as string
+    );
+  } catch (err) {
+    const errorMessage = err instanceof Error ? err.message : 'Unknown error';
+    // On error, log and return the error message.
+    if (err! instanceof Error) console.log(err);
+    console.log(`❌ Error message: ${errorMessage}`);
+    return NextResponse.json(
+      {message: `Webhook Error: ${errorMessage}`},
+      {status: 400}
+    );
+  }
+
+  // Successfully constructed event.
+  console.log('✅ Success:', event.id);
+
+  const permittedEvents: string[] = [
+    'checkout.session.completed',
+    'payment_intent.succeeded',
+    'payment_intent.payment_failed',
+  ];
+
+  if (permittedEvents.includes(event.type)) {
+    let data;
+
+    try {
+      switch (event.type) {
+        case 'checkout.session.completed':
+          data = event.data.object as Stripe.Checkout.Session;
+          console.log(`💰 CheckoutSession status: ${data.payment_status}`);
+          break;
+        case 'payment_intent.payment_failed':
+          data = event.data.object as Stripe.PaymentIntent;
+          console.log(`❌ Payment failed: ${data.last_payment_error?.message}`);
+          break;
+        case 'payment_intent.succeeded':
+          data = event.data.object as Stripe.PaymentIntent;
+          console.log(`💰 PaymentIntent status: ${data.status}`);
+          break;
+        default:
+          throw new Error(`Unhandled event: ${event.type}`);
+      }
+    } catch (error) {
+      console.log(error);
+      return NextResponse.json(
+        {message: 'Webhook handler failed'},
+        {status: 500}
+      );
+    }
+  }
+
+  // Return a response to acknowledge receipt of the event.
+  return NextResponse.json({message: 'Received'}, {status: 200});
+}