fix: 404 status in ssr (#14884)

florian-lefebvre · web-flow · commit 10273e01357e · 2025-11-27T09:23:53.000+01:00
diff --git a/.changeset/stale-webs-tie.md b/.changeset/stale-webs-tie.md
@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixes a case where setting the status of a page to `404` in ssr would show an empty page (or `404.astro` page if provided) instead of using the current page
diff --git a/packages/astro/src/core/app/index.ts b/packages/astro/src/core/app/index.ts
@@ -559,6 +559,9 @@ export class App {
 
 		if (
 			REROUTABLE_STATUS_CODES.includes(response.status) &&
+			// If the body isn't null, that means the user sets the 404 status
+			// but uses the current route to handle the 404
+			response.body === null &&
 			response.headers.get(REROUTE_DIRECTIVE_HEADER) !== 'no'
 		) {
 			return this.#renderError(request, {
diff --git a/packages/astro/test/fixtures/ssr-response/src/pages/404.astro b/packages/astro/test/fixtures/ssr-response/src/pages/404.astro
@@ -0,0 +1,8 @@
+<html>
+	<head>
+		<title>Custom 404</title>
+	</head>
+	<body>
+		<h1>Custom 404</h1>
+	</body>
+</html>
diff --git a/packages/astro/test/ssr-response.test.js b/packages/astro/test/ssr-response.test.js
@@ -38,6 +38,15 @@ describe('Using Astro.response in SSR', () => {
 		assert.equal(headers.get('one-two'), 'three');
 	});
 
+	it('Returns the page, not the custom 404.astro', async () => {
+		const app = await fixture.loadTestAdapterApp();
+		const request = new Request('http://example.com/status-code');
+		const response = await app.render(request);
+		const html = await response.text()
+		assert.equal(html.includes('<h1>Testing</h1>'), true);
+		assert.equal(html.includes('<h1>Custom 404</h1>'), false);
+	});
+
 	it('Can add headers', async () => {
 		const app = await fixture.loadTestAdapterApp();
 		const request = new Request('http://example.com/some-header');

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +---
 +'astro': patch
 +---
++
 +Fixes a case where setting the status of a page to `404` in ssr would show an empty page (or `404.astro` page if provided) instead of using the current page