diff --git a/.changeset/stale-pandas-count.md b/.changeset/stale-pandas-count.md
new file mode 100644
index 000000000000..b67de833cf80
--- /dev/null
+++ b/.changeset/stale-pandas-count.md
@@ -0,0 +1,5 @@
+---
+"@astrojs/vercel": patch
+---
+
+Fixes an issue where the serverless function could not respond with a prerendered 404 page.
diff --git a/packages/integrations/vercel/src/serverless/adapter.ts b/packages/integrations/vercel/src/serverless/adapter.ts
index dd07e723b644..db7f428051e1 100644
--- a/packages/integrations/vercel/src/serverless/adapter.ts
+++ b/packages/integrations/vercel/src/serverless/adapter.ts
@@ -287,9 +287,15 @@ You can set functionPerRoute: false to prevent surpassing the limit.`
excludeFiles,
maxDuration,
});
- routeDefinitions.push({ src: '/.*', dest: 'render' });
+ for (const route of routes) {
+ if (route.prerender) continue
+ routeDefinitions.push({
+ src: route.pattern.source,
+ dest: 'render',
+ })
+ }
}
-
+ const fourOhFourRoute = routes.find((route) => route.pathname === '/404');
// Output configuration
// https://vercel.com/docs/build-output-api/v3#build-output-configuration
await writeJson(new URL(`./config.json`, _config.outDir), {
@@ -303,6 +309,11 @@ You can set functionPerRoute: false to prevent surpassing the limit.`
},
{ handle: 'filesystem' },
...routeDefinitions,
+ ...fourOhFourRoute ? [{
+ src: '/.*',
+ dest: fourOhFourRoute.prerender ? '/404.html' : 'render',
+ status: 404,
+ }] : [],
],
...(imageService || imagesConfig
? {
diff --git a/packages/integrations/vercel/test/fixtures/prerendered-error-pages/astro.config.mjs b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/astro.config.mjs
new file mode 100644
index 000000000000..b3f5bd362bae
--- /dev/null
+++ b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/astro.config.mjs
@@ -0,0 +1,7 @@
+import { defineConfig } from 'astro/config';
+import vercel from '@astrojs/vercel/serverless';
+
+export default defineConfig({
+ output: 'server',
+ adapter: vercel()
+});
diff --git a/packages/integrations/vercel/test/fixtures/prerendered-error-pages/package.json b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/package.json
new file mode 100644
index 000000000000..5cfc0e24c44d
--- /dev/null
+++ b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/package.json
@@ -0,0 +1,9 @@
+{
+ "name": "@test/astro-vercel-prerendered-error-pages",
+ "version": "0.0.0",
+ "private": true,
+ "dependencies": {
+ "@astrojs/vercel": "workspace:*",
+ "astro": "workspace:*"
+ }
+}
diff --git a/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/404.astro b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/404.astro
new file mode 100644
index 000000000000..162ff90b6820
--- /dev/null
+++ b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/404.astro
@@ -0,0 +1,4 @@
+---
+export const prerender = true
+---
+404
diff --git a/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/one.astro b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/one.astro
new file mode 100644
index 000000000000..0c7fb90a735e
--- /dev/null
+++ b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/one.astro
@@ -0,0 +1,8 @@
+
+
+ One
+
+
+ One
+
+
diff --git a/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/two.astro b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/two.astro
new file mode 100644
index 000000000000..e7ba9910e2a6
--- /dev/null
+++ b/packages/integrations/vercel/test/fixtures/prerendered-error-pages/src/pages/two.astro
@@ -0,0 +1,8 @@
+
+
+ Two
+
+
+ Two
+
+
diff --git a/packages/integrations/vercel/test/prerendered-error-pages.test.js b/packages/integrations/vercel/test/prerendered-error-pages.test.js
new file mode 100644
index 000000000000..9085662238d8
--- /dev/null
+++ b/packages/integrations/vercel/test/prerendered-error-pages.test.js
@@ -0,0 +1,23 @@
+import { loadFixture } from './test-utils.js';
+import { expect } from 'chai';
+
+describe('prerendered error pages routing', () => {
+ /** @type {import('./test-utils.js').Fixture} */
+ let fixture;
+
+ before(async () => {
+ fixture = await loadFixture({
+ root: './fixtures/prerendered-error-pages/',
+ });
+ await fixture.build();
+ });
+
+ it('falls back to 404.html', async () => {
+ const deploymentConfig = JSON.parse(await fixture.readFile('../.vercel/output/config.json'));
+ expect(deploymentConfig.routes.at(-1)).to.deep.include({
+ src: '/.*',
+ dest: '/404.html',
+ status: 404,
+ });
+ });
+});
diff --git a/packages/integrations/vercel/test/static.test.js b/packages/integrations/vercel/test/static.test.js
index fc97e46ad7e9..a3d0ea738272 100644
--- a/packages/integrations/vercel/test/static.test.js
+++ b/packages/integrations/vercel/test/static.test.js
@@ -1,7 +1,7 @@
import { loadFixture } from './test-utils.js';
import { expect } from 'chai';
-describe('maxDuration', () => {
+describe('static routing', () => {
/** @type {import('./test-utils.js').Fixture} */
let fixture;
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 7dd02558ad6a..69b6abd703bf 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -4749,6 +4749,15 @@ importers:
specifier: workspace:*
version: link:../../../../../astro
+ packages/integrations/vercel/test/fixtures/prerendered-error-pages:
+ dependencies:
+ '@astrojs/vercel':
+ specifier: workspace:*
+ version: link:../../..
+ astro:
+ specifier: workspace:*
+ version: link:../../../../../astro
+
packages/integrations/vercel/test/fixtures/redirects:
dependencies:
'@astrojs/vercel':