From ab9c14b5ac1f4a974e8e2eca7414d6b30c8bd191 Mon Sep 17 00:00:00 2001
From: Jiachi Liu <inbox@huozhi.im>
Date: Wed, 7 Aug 2024 09:41:45 +0200
Subject: [PATCH 1/2] Ensure next-server prepare only execute once

---
 .../instrumentation-hook/register-once/instrumentation.js   | 6 ++++++
 .../register-once/register-once.test.ts                     | 6 ++++++
 2 files changed, 12 insertions(+)

diff --git a/test/e2e/instrumentation-hook/register-once/instrumentation.js b/test/e2e/instrumentation-hook/register-once/instrumentation.js
index f96e7a7d10a966..276640bdd6071d 100644
--- a/test/e2e/instrumentation-hook/register-once/instrumentation.js
+++ b/test/e2e/instrumentation-hook/register-once/instrumentation.js
@@ -1,5 +1,11 @@
+let count = 0
+
 export function register() {
   if (process.env.NEXT_RUNTIME === 'nodejs') {
+    if (count > 0) {
+      throw new Error('duplicated-register')
+    }
     console.log('register-log')
+    count++
   }
 }
diff --git a/test/e2e/instrumentation-hook/register-once/register-once.test.ts b/test/e2e/instrumentation-hook/register-once/register-once.test.ts
index 88bbb39ac7bb23..19b0ddb843787c 100644
--- a/test/e2e/instrumentation-hook/register-once/register-once.test.ts
+++ b/test/e2e/instrumentation-hook/register-once/register-once.test.ts
@@ -14,4 +14,10 @@ describe('instrumentation-hook - register-once', () => {
     await next.fetch('/foo')
     expect(next.cliOutput).toIncludeRepeated('register-log', 1)
   })
+
+  it('should not error when concurrent requests are made', async () => {
+    await Promise.all([next.fetch('/foo'), next.fetch('/foo')])
+    expect(next.cliOutput).toIncludeRepeated('register-log', 1)
+    expect(next.cliOutput).not.toInclude('duplicated-register')
+  })
 })

From f416a349d183ef1723e3adf99166edfb89c7dca6 Mon Sep 17 00:00:00 2001
From: Jiachi Liu <inbox@huozhi.im>
Date: Wed, 7 Aug 2024 18:40:49 +0200
Subject: [PATCH 2/2] ensure register only get called once

---
 packages/next/src/server/next-server.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/packages/next/src/server/next-server.ts b/packages/next/src/server/next-server.ts
index f7cb690d004b4c..cc24a570a85f01 100644
--- a/packages/next/src/server/next-server.ts
+++ b/packages/next/src/server/next-server.ts
@@ -156,6 +156,7 @@ export default class NextNodeServer extends BaseServer<
   protected middlewareManifestPath: string
   private _serverDistDir: string | undefined
   private imageResponseCache?: ResponseCache
+  private registeredInstrumentation: boolean = false
   protected renderWorkersPromises?: Promise<void>
   protected dynamicRoutes?: {
     match: import('../shared/lib/router/utils/route-matcher').RouteMatchFn
@@ -324,6 +325,8 @@ export default class NextNodeServer extends BaseServer<
   }
 
   protected async runInstrumentationHookIfAvailable() {
+    if (this.registeredInstrumentation) return
+    this.registeredInstrumentation = true
     await this.instrumentation?.register?.()
   }