feat(nuxt): experimental extraPageMetaExtractionKeys (nuxt#30015)

docs/2.guide/3.going-further/1.experimental-features.md

@@ -395,6 +395,35 @@ In addition, any changes to files within `srcDir` will trigger a rebuild of the
 A maximum of 10 cache tarballs are kept.
 ::
 
+## extraPageMetaExtractionKeys
+
+The `definePageMeta()` macro is a useful way to collect build-time meta about pages. Nuxt itself provides a set list of supported keys which is used to power some of the internal features such as redirects, page aliases and custom paths.
+
+This option allows passing additional keys to extract from the page metadata when using `scanPageMeta`.
+
+```vue
+<script lang="ts" setup>
+definePageMeta({
+  foo: 'bar'
+})
+</script>
+```
+
+```ts
+export default defineNuxtConfig({
+  experimental: {
+    extraPageMetaExtractionKeys: ['foo'],
+  },
+  hooks: {
+    'pages:resolved' (ctx) {
+      // ✅ foo is available
+    },
+  },
+})
+```
+
+This allows modules to access additional metadata from the page metadata in the build context. If you are using this within a module, it's recommended also to [augment the `NuxtPage` types with your keys](/docs/guide/directory-structure/pages#typing-custom-metadata).
+
 ## normalizeComponentNames
 
 Ensure that auto-generated Vue component names match the full component name

packages/nuxt/src/pages/utils.ts

@@ -71,13 +71,14 @@ export async function resolvePagesRoutes (): Promise<NuxtPage[]> {
     return pages
   }
 
+  const augmentCtx = { extraExtractionKeys: nuxt.options.experimental.extraPageMetaExtractionKeys }
   if (shouldAugment === 'after-resolve') {
     await nuxt.callHook('pages:extend', pages)
-    await augmentPages(pages, nuxt.vfs)
+    await augmentPages(pages, nuxt.vfs, augmentCtx)
   } else {
-    const augmentedPages = await augmentPages(pages, nuxt.vfs)
+    const augmentedPages = await augmentPages(pages, nuxt.vfs, augmentCtx)
     await nuxt.callHook('pages:extend', pages)
-    await augmentPages(pages, nuxt.vfs, { pagesToSkip: augmentedPages })
+    await augmentPages(pages, nuxt.vfs, { pagesToSkip: augmentedPages, ...augmentCtx })
     augmentedPages?.clear()
   }
 
@@ -158,13 +159,15 @@ export function generateRoutesFromFiles (files: ScannedFile[], options: Generate
 interface AugmentPagesContext {
   pagesToSkip?: Set<string>
   augmentedPages?: Set<string>
+  extraExtractionKeys?: string[]
 }
+
 export async function augmentPages (routes: NuxtPage[], vfs: Record<string, string>, ctx: AugmentPagesContext = {}) {
   ctx.augmentedPages ??= new Set()
   for (const route of routes) {
     if (route.file && !ctx.pagesToSkip?.has(route.file)) {
       const fileContent = route.file in vfs ? vfs[route.file]! : fs.readFileSync(await resolvePath(route.file), 'utf-8')
-      const routeMeta = await getRouteMeta(fileContent, route.file)
+      const routeMeta = await getRouteMeta(fileContent, route.file, ctx.extraExtractionKeys)
       if (route.meta) {
         routeMeta.meta = { ...routeMeta.meta, ...route.meta }
       }
@@ -196,12 +199,12 @@ export function extractScriptContent (html: string) {
 }
 
 const PAGE_META_RE = /definePageMeta\([\s\S]*?\)/
-const extractionKeys = ['name', 'path', 'props', 'alias', 'redirect'] as const
+const defaultExtractionKeys = ['name', 'path', 'props', 'alias', 'redirect'] as const
 const DYNAMIC_META_KEY = '__nuxt_dynamic_meta_key' as const
 
 const pageContentsCache: Record<string, string> = {}
 const metaCache: Record<string, Partial<Record<keyof NuxtPage, any>>> = {}
-export async function getRouteMeta (contents: string, absolutePath: string): Promise<Partial<Record<keyof NuxtPage, any>>> {
+export async function getRouteMeta (contents: string, absolutePath: string, extraExtractionKeys: string[] = []): Promise<Partial<Record<keyof NuxtPage, any>>> {
   // set/update pageContentsCache, invalidate metaCache on cache mismatch
   if (!(absolutePath in pageContentsCache) || pageContentsCache[absolutePath] !== contents) {
     pageContentsCache[absolutePath] = contents
@@ -221,6 +224,8 @@ export async function getRouteMeta (contents: string, absolutePath: string): Pro
 
   const extractedMeta = {} as Partial<Record<keyof NuxtPage, any>>
 
+  const extractionKeys = new Set<keyof NuxtPage>([...defaultExtractionKeys, ...extraExtractionKeys as Array<keyof NuxtPage>])
+
   for (const script of scriptBlocks) {
     if (!PAGE_META_RE.test(script.code)) {
       continue
@@ -295,7 +300,7 @@ export async function getRouteMeta (contents: string, absolutePath: string): Pro
             continue
           }
           const name = property.key.type === 'Identifier' ? property.key.name : String(property.value)
-          if (!(extractionKeys as unknown as string[]).includes(name)) {
+          if (!extractionKeys.has(name as keyof NuxtPage)) {
             dynamicProperties.add('meta')
             break
           }

packages/nuxt/test/page-metadata.test.ts

@@ -142,6 +142,24 @@ describe('page metadata', () => {
       }
     `)
   })
+
+  it('should extract configured extra meta', async () => {
+    const meta = await getRouteMeta(`
+    <script setup>
+    definePageMeta({
+      foo: 'bar',
+      bar: true,
+    })
+    </script>
+    `, filePath, ['bar', 'foo'])
+
+    expect(meta).toMatchInlineSnapshot(`
+      {
+        "bar": true,
+        "foo": "bar",
+      }
+    `)
+  })
 })
 
 describe('normalizeRoutes', () => {

packages/schema/src/config/experimental.ts

@@ -308,6 +308,16 @@ export default defineUntypedSchema({
       },
     },
 
+    /**
+     * Configure additional keys to extract from the page metadata when using `scanPageMeta`.
+     *
+     * This allows modules to access additional metadata from the page metadata. It's recommended
+     * to augment the NuxtPage types with your keys.
+     *
+     * @type {string[]}
+     */
+    extraPageMetaExtractionKeys: [],
+
     /**
      * Automatically share payload _data_ between pages that are prerendered. This can result in a significant
      * performance improvement when prerendering sites that use `useAsyncData` or `useFetch` and fetch the same