fix(nuxt): use routeRules to hint pages to prerender (#29172)

packages/nuxt/src/core/templates.ts

@@ -8,6 +8,7 @@ import { hash } from 'ohash'
 import { camelCase } from 'scule'
 import { filename } from 'pathe/utils'
 import type { NuxtTemplate, NuxtTypeTemplate } from 'nuxt/schema'
+import type { Nitro } from 'nitropack'
 
 import { annotatePlugins, checkForCircularDependencies } from './app'
 
@@ -512,6 +513,7 @@ export const nuxtConfigTemplate: NuxtTemplate = {
       `export const outdatedBuildInterval = ${ctx.nuxt.options.experimental.checkOutdatedBuildInterval}`,
       `export const multiApp = ${!!ctx.nuxt.options.future.multiApp}`,
       `export const chunkErrorEvent = ${ctx.nuxt.options.experimental.emitRouteChunkError ? ctx.nuxt.options.builder === '@nuxt/vite-builder' ? '"vite:preloadError"' : '"nuxt:preloadError"' : 'false'}`,
+      `export const crawlLinks = ${!!((ctx.nuxt as any)._nitro as Nitro).options.prerender.crawlLinks}`,
     ].join('\n\n')
   },
 }

packages/nuxt/src/pages/module.ts

@@ -8,6 +8,7 @@ import type { Nuxt, NuxtApp, NuxtPage } from 'nuxt/schema'
 import { createRoutesContext } from 'unplugin-vue-router'
 import { resolveOptions } from 'unplugin-vue-router/options'
 import type { EditableTreeNode, Options as TypedRouterOptions } from 'unplugin-vue-router'
+import { createRouter as createRadixRouter, toRouteMatcher } from 'radix3'
 
 import type { NitroRouteConfig } from 'nitropack'
 import { defu } from 'defu'
@@ -272,7 +273,7 @@ export default defineNuxtModule({
 
     nuxt.hook('app:resolve', (app) => {
       const nitro = useNitro()
-      if (nitro.options.prerender.crawlLinks) {
+      if (nitro.options.prerender.crawlLinks || Object.values(nitro.options.routeRules).some(rule => rule.prerender)) {
         app.plugins.push({
           src: resolve(runtimeDir, 'plugins/prerender.server'),
           mode: 'server',
@@ -310,7 +311,20 @@ export default defineNuxtModule({
     })
 
     nuxt.hook('nitro:build:before', (nitro) => {
-      if (nuxt.options.dev || !nitro.options.static || nuxt.options.router.options.hashMode || !nitro.options.prerender.crawlLinks) { return }
+      if (nuxt.options.dev || nuxt.options.router.options.hashMode) { return }
+
+      // Inject page patterns that explicitly match `prerender: true` route rule
+      if (!nitro.options.static && !nitro.options.prerender.crawlLinks) {
+        const routeRulesMatcher = toRouteMatcher(createRadixRouter({ routes: nitro.options.routeRules }))
+        for (const route of prerenderRoutes) {
+          const rules = defu({} as Record<string, any>, ...routeRulesMatcher.matchAll(route).reverse())
+          if (rules.prerender) {
+            nitro.options.prerender.routes.push(route)
+          }
+        }
+      }
+
+      if (!nitro.options.static || !nitro.options.prerender.crawlLinks) { return }
 
       // Only hint the first route when `ssr: true` and no routes are provided
       // as the rest will be injected at runtime when this is prerendered

packages/nuxt/src/pages/runtime/plugins/prerender.server.ts

@@ -1,20 +1,31 @@
 import type { RouteRecordRaw } from 'vue-router'
 import { joinURL } from 'ufo'
+import { createRouter as createRadixRouter, toRouteMatcher } from 'radix3'
+import defu from 'defu'
 
-import { defineNuxtPlugin } from '#app/nuxt'
+import { defineNuxtPlugin, useRuntimeConfig } from '#app/nuxt'
 import { prerenderRoutes } from '#app/composables/ssr'
 // @ts-expect-error virtual file
 import _routes from '#build/routes'
 import routerOptions from '#build/router.options'
+// @ts-expect-error virtual file
+import { crawlLinks } from '#build/nuxt.config.mjs'
 
 let routes: string[]
 
+let _routeRulesMatcher: undefined | ReturnType<typeof toRouteMatcher> = undefined
+
 export default defineNuxtPlugin(async () => {
   if (!import.meta.server || !import.meta.prerender || routerOptions.hashMode) {
     return
   }
   if (routes && !routes.length) { return }
 
+  const routeRules = useRuntimeConfig().nitro!.routeRules
+  if (!crawlLinks && routeRules && Object.values(routeRules).some(r => r.prerender)) {
+    _routeRulesMatcher = toRouteMatcher(createRadixRouter({ routes: routeRules }))
+  }
+
   routes ||= Array.from(processRoutes(await routerOptions.routes?.(_routes) ?? _routes))
   const batch = routes.splice(0, 10)
   prerenderRoutes(batch)
@@ -24,10 +35,14 @@ export default defineNuxtPlugin(async () => {
 
 const OPTIONAL_PARAM_RE = /^\/?:.*(?:\?|\(\.\*\)\*)$/
 
+function shouldPrerender (path: string) {
+  return !_routeRulesMatcher || defu({} as Record<string, any>, ..._routeRulesMatcher.matchAll(path).reverse()).prerender
+}
+
 function processRoutes (routes: RouteRecordRaw[], currentPath = '/', routesToPrerender = new Set<string>()) {
   for (const route of routes) {
     // Add root of optional dynamic paths and catchalls
-    if (OPTIONAL_PARAM_RE.test(route.path) && !route.children?.length) {
+    if (OPTIONAL_PARAM_RE.test(route.path) && !route.children?.length && shouldPrerender(currentPath)) {
       routesToPrerender.add(currentPath)
     }
     // Skip dynamic paths
@@ -35,7 +50,9 @@ function processRoutes (routes: RouteRecordRaw[], currentPath = '/', routesToPre
       continue
     }
     const fullPath = joinURL(currentPath, route.path)
-    routesToPrerender.add(fullPath)
+    if (shouldPrerender(fullPath)) {
+      routesToPrerender.add(fullPath)
+    }
     if (route.children) {
       processRoutes(route.children, fullPath, routesToPrerender)
     }

test/basic.test.ts

@@ -618,6 +618,11 @@ describe('pages', () => {
       expect(status).toBe(200)
     }
   })
+
+  it.skipIf(isDev() || isWebpack /* TODO: fix bug with import.meta.prerender being undefined in webpack build */)('prerenders pages hinted with a route rule', async () => {
+    const html = await $fetch('/prerender/test')
+    expect(html).toContain('should be prerendered: true')
+  })
 })
 
 describe('nuxt composables', () => {

test/fixtures/basic/nuxt.config.ts

@@ -67,6 +67,7 @@ export default defineNuxtConfig({
       '/route-rules/middleware': { appMiddleware: 'route-rules-middleware' },
       '/hydration/spa-redirection/**': { ssr: false },
       '/no-scripts': { experimentalNoScripts: true },
+      '/prerender/**': { prerender: true },
     },
     output: { dir: process.env.NITRO_OUTPUT_DIR },
     prerender: {

test/fixtures/basic/pages/prerender/test.vue

@@ -0,0 +1,9 @@
+<script setup lang="ts">
+const wasPrerendered = useState(() => import.meta.prerender)
+</script>
+
+<template>
+  <div>
+    should be prerendered: {{ wasPrerendered }}
+  </div>
+</template>