test(e2e): Add test for Next.js middleware

packages/e2e-tests/test-applications/nextjs-app-dir/middleware.ts

@@ -0,0 +1,11 @@
+import { NextResponse } from 'next/server';
+import type { NextRequest } from 'next/server';
+
+export function middleware() {
+  return NextResponse.next();
+}
+
+// See "Matching Paths" below to learn more
+export const config = {
+  matcher: ['/api/endpoint-behind-middleware'],
+};

packages/e2e-tests/test-applications/nextjs-app-dir/pages/api/endpoint-behind-middleware.ts

@@ -0,0 +1,9 @@
+import type { NextApiRequest, NextApiResponse } from 'next';
+
+type Data = {
+  name: string;
+};
+
+export default function handler(req: NextApiRequest, res: NextApiResponse<Data>) {
+  res.status(200).json({ name: 'John Doe' });
+}

packages/e2e-tests/test-applications/nextjs-app-dir/tests/transactions.test.ts

@@ -112,3 +112,18 @@ if (process.env.TEST_ENV === 'production') {
     expect((await serverComponentTransactionPromise).contexts?.trace?.status).toBe('not_found');
   });
 }
+
+test('Should create a transaction for middleware', async ({ request }) => {
+  const middlewareTransactionPromise = waitForTransaction('nextjs-13-app-dir', async transactionEvent => {
+    return transactionEvent?.transaction === 'middleware';
+  });
+
+  const response = await request.get('/api/endpoint-behind-middleware');
+  expect(await response.json()).toStrictEqual({ name: 'John Doe' });
+
+  const middlewareTransaction = await middlewareTransactionPromise;
+
+  expect(middlewareTransaction.contexts?.trace?.status).toBe('ok');
+  expect(middlewareTransaction.contexts?.trace?.op).toBe('middleware.nextjs');
+  expect(middlewareTransaction.contexts?.runtime?.name).toBe('edge');
+});