fixup! fix(@angular/build): Add custom middleware for to present an Angular-tailored message

alan-agius4 · alan-agius4 · commit a517beb1b9b7 · 2025-12-09T17:00:46.000Z
diff --git a/packages/angular/build/src/tools/vite/middlewares/host-check-middleware.ts b/packages/angular/build/src/tools/vite/middlewares/host-check-middleware.ts
@@ -6,7 +6,43 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-export function html403(hostname: string): string {
+import type { IncomingMessage, ServerResponse } from 'node:http';
+import type { Connect } from 'vite';
+
+export function createAngularHostCheckMiddleware(middlewares: Connect.Server): void {
+  const entry = middlewares.stack.find(
+    ({ handle }) =>
+      typeof handle === 'function' && handle.name.startsWith('hostValidationMiddleware'),
+  );
+
+  if (typeof entry?.handle !== 'function') {
+    return;
+  }
+
+  const originalHandle = entry.handle as Connect.NextHandleFunction;
+
+  entry.handle = function angularHostValidationMiddleware(
+    req: IncomingMessage,
+    res: ServerResponse,
+    next: (err?: unknown) => void,
+  ) {
+    originalHandle(
+      req,
+      {
+        writeHead: (code) => {
+          res.writeHead(code, { 'content-type': 'text/html' });
+        },
+        end: () => {
+          const hostname = req.headers.host?.toLowerCase().split(':')[0] ?? '';
+          res.end(html403(hostname));
+        },
+      } as ServerResponse,
+      next,
+    );
+  };
+}
+
+function html403(hostname: string): string {
   return `<!doctype html>
 <html>
   <head>
diff --git a/packages/angular/build/src/tools/vite/middlewares/index.ts b/packages/angular/build/src/tools/vite/middlewares/index.ts
@@ -16,4 +16,4 @@ export {
 export { createAngularHeadersMiddleware } from './headers-middleware';
 export { createAngularComponentMiddleware } from './component-middleware';
 export { createChromeDevtoolsMiddleware } from './chrome-devtools-middleware';
-export { html403 } from './host-check-middleware';
+export { createAngularHostCheckMiddleware } from './host-check-middleware';
diff --git a/packages/angular/build/src/tools/vite/plugins/setup-middlewares-plugin.ts b/packages/angular/build/src/tools/vite/plugins/setup-middlewares-plugin.ts
@@ -6,19 +6,18 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-import { IncomingMessage, ServerResponse } from 'node:http';
 import type { Connect, Plugin } from 'vite';
 import {
   ComponentStyleRecord,
   angularHtmlFallbackMiddleware,
   createAngularAssetsMiddleware,
   createAngularComponentMiddleware,
   createAngularHeadersMiddleware,
+  createAngularHostCheckMiddleware,
   createAngularIndexHtmlMiddleware,
   createAngularSsrExternalMiddleware,
   createAngularSsrInternalMiddleware,
   createChromeDevtoolsMiddleware,
-  html403,
 } from '../middlewares';
 import { AngularMemoryOutputFiles, AngularOutputAssets } from '../utils';
 
@@ -113,35 +112,7 @@ export function createAngularSetupMiddlewaresPlugin(
       // before the built-in HTML middleware
       // eslint-disable-next-line @typescript-eslint/no-misused-promises
       return async () => {
-        // Vite/Connect do not expose a typed stack, cast once to a precise structural type.
-        const entry = server.middlewares.stack.find(
-          ({ handle }) =>
-            typeof handle === 'function' && handle.name.startsWith('hostValidationMiddleware'),
-        );
-
-        if (typeof entry?.handle === 'function') {
-          const originalHandle = entry.handle as Connect.NextHandleFunction;
-
-          entry.handle = function angularHostValidationMiddleware(
-            req: IncomingMessage,
-            res: ServerResponse,
-            next: (err?: unknown) => void,
-          ) {
-            originalHandle(
-              req,
-              {
-                writeHead: (code) => {
-                  res.writeHead(code, { 'content-type': 'text/html' });
-                },
-                end: () => {
-                  const hostname = req.headers.host?.toLowerCase().split(':')[0] ?? '';
-                  res.end(html403(hostname));
-                },
-              } as ServerResponse,
-              next,
-            );
-          };
-        }
+        createAngularHostCheckMiddleware(server.middlewares);
 
         if (ssrMode === ServerSsrMode.ExternalSsrMiddleware) {
           server.middlewares.use(
