fix(astro): correctly export build.assetsPrefix from astro:config/server

.changeset/neat-towns-do.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixes `assetsPrefix` not being available on `build` from `astro:config/server`.

packages/astro/src/manifest/virtual-module.ts

@@ -118,6 +118,7 @@ const build = {
   server: new URL(manifest.buildServerDir),
   client: new URL(manifest.buildClientDir),
   format: manifest.buildFormat,
+  assetsPrefix: manifest.assetsPrefix,
 };
 
 const cacheDir = new URL(manifest.cacheDir);

packages/astro/src/types/public/manifest.ts

@@ -25,7 +25,7 @@ export type ServerDeserializedManifest = Pick<
 > &
 	DeserializedDirs & {
 		i18n: AstroConfig['i18n'];
-		build: Pick<AstroConfig['build'], 'server' | 'client' | 'format'>;
+		build: Pick<AstroConfig['build'], 'server' | 'client' | 'format' | 'assetsPrefix'>;
 		root: URL;
 		image: Pick<AstroConfig['image'], 'objectFit' | 'objectPosition' | 'layout'>;
 	};

packages/astro/test/fixtures/astro-manifest/astro.config.mjs

@@ -2,6 +2,9 @@ import { defineConfig } from "astro/config";
 
 // https://astro.build/config
 export default defineConfig({
+	build: {
+		assetsPrefix: 'https://cdn.example.com',
+	},
 	site: "https://astro.build/",
 	i18n: {
 		locales: ["en", "fr"],

packages/astro/test/fixtures/astro-manifest/src/pages/server.astro

@@ -18,5 +18,6 @@ import { root, outDir, srcDir, build, cacheDir } from "astro:config/server";
 <p id="cache-dir">{cacheDir}</p>
 <p id="build-client">{build.client}</p>
 <p id="build-server">{build.server}</p>
+<p id="build-assets-prefix">{build.assetsPrefix}</p>
 </body>
 </html>

packages/astro/test/serializeManifest.test.ts

@@ -116,6 +116,7 @@ describe('astro:config/server', () => {
 					.text()
 					.endsWith('/dist/serializeManifest-when-the-experimental-flag-is-enabled-in/server/'),
 			);
+			assert.equal($('#build-assets-prefix').text(), 'https://cdn.example.com');
 			// URL
 			assert.equal($('#root-url').text(), 'true');
 		});
@@ -158,6 +159,7 @@ describe('astro:config/server', () => {
 					.text()
 					.endsWith('/dist/serializeManifest-when-the-experimental-flag-is-enabled-in-ssr/server/'),
 			);
+			assert.equal($('#build-assets-prefix').text(), 'https://cdn.example.com');
 			// URL
 			assert.equal($('#root-url').text(), 'true');
 		});