From 5d57541ca4d46106035e75ae136d53926a3d17a1 Mon Sep 17 00:00:00 2001
From: gtmnayan <gtmnayan@gmail.com>
Date: Sun, 7 May 2023 08:07:02 +0545
Subject: [PATCH 1/2] fix: handle ping requests before they reach user
 middleware

---
 packages/vite/src/client/client.ts     | 5 +++++
 packages/vite/src/node/server/index.ts | 9 +++++++++
 2 files changed, 14 insertions(+)

diff --git a/packages/vite/src/client/client.ts b/packages/vite/src/client/client.ts
index ed1cab3eb17c2e..0abf5bccef0944 100644
--- a/packages/vite/src/client/client.ts
+++ b/packages/vite/src/client/client.ts
@@ -321,6 +321,11 @@ async function waitForSuccessfulPing(
     try {
       await fetch(`${pingHostProtocol}://${hostAndPath}`, {
         mode: 'no-cors',
+        headers: {
+          // Custom headers won't be included in a request with no-cors so (ab)use one of the
+          // safelisted headers to identify the ping request
+          Accept: 'text/x-vite-ping',
+        },
       })
       return true
     } catch {}
diff --git a/packages/vite/src/node/server/index.ts b/packages/vite/src/node/server/index.ts
index 0831cd01fe3743..b8abda786fb941 100644
--- a/packages/vite/src/node/server/index.ts
+++ b/packages/vite/src/node/server/index.ts
@@ -608,6 +608,15 @@ export async function _createServer(
   // open in editor support
   middlewares.use('/__open-in-editor', launchEditorMiddleware())
 
+  // ping request handler
+  middlewares.use((req, res, next) => {
+    if (req.headers['accept'] === 'text/x-vite-ping') {
+      res.writeHead(204).end()
+    } else {
+      next()
+    }
+  })
+
   // serve static files under /public
   // this applies before the transform middleware so that these files are served
   // as-is without transforms.

From 0e58633a08de02d40351427aec7ce66851cf38fc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=BF=A0=20/=20green?= <green@sapphi.red>
Date: Tue, 9 May 2023 00:25:12 +0900
Subject: [PATCH 2/2] chore: make it a named function

---
 packages/vite/src/node/server/index.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/vite/src/node/server/index.ts b/packages/vite/src/node/server/index.ts
index b8abda786fb941..541372996c2f4b 100644
--- a/packages/vite/src/node/server/index.ts
+++ b/packages/vite/src/node/server/index.ts
@@ -609,7 +609,8 @@ export async function _createServer(
   middlewares.use('/__open-in-editor', launchEditorMiddleware())
 
   // ping request handler
-  middlewares.use((req, res, next) => {
+  // Keep the named function. The name is visible in debug logs via `DEBUG=connect:dispatcher ...`
+  middlewares.use(function viteHMRPingMiddleware(req, res, next) {
     if (req.headers['accept'] === 'text/x-vite-ping') {
       res.writeHead(204).end()
     } else {