feat: improve base url options (#2655)

packages/bridge/src/nitro.ts

@@ -15,6 +15,13 @@ export function setupNitroBridge () {
     throw new Error('[nitro] Please use `nuxt generate` for static target')
   }
 
+  // Handle legacy property name `assetsPath`
+  nuxt.options.app.buildAssetsDir = nuxt.options.app.buildAssetsDir || nuxt.options.app.assetsPath
+  nuxt.options.app.assetsPath = nuxt.options.app.buildAssetsDir
+  // Nitro expects app config on `config.app` rather than `config._app`
+  nuxt.options.publicRuntimeConfig.app = nuxt.options.publicRuntimeConfig.app || {}
+  Object.assign(nuxt.options.publicRuntimeConfig.app, nuxt.options.publicRuntimeConfig._app)
+
   // Disable loading-screen
   // @ts-ignore
   nuxt.options.build.loadingScreen = false

packages/bridge/src/vite/client.ts

@@ -3,6 +3,7 @@ import * as vite from 'vite'
 import { createVuePlugin } from 'vite-plugin-vue2'
 import PluginLegacy from '@vitejs/plugin-legacy'
 import consola from 'consola'
+import { joinURL } from 'ufo'
 import { devStyleSSRPlugin } from '../../../vite/src/plugins/dev-ssr-css'
 import { jsxPlugin } from './plugins/jsx'
 import { ViteBuildContext, ViteOptions } from './types'
@@ -28,7 +29,6 @@ export async function buildClient (ctx: ViteBuildContext) {
     },
     build: {
       outDir: resolve(ctx.nuxt.options.buildDir, 'dist/client'),
-      assetsDir: '.',
       rollupOptions: {
         input: resolve(ctx.nuxt.options.buildDir, 'client.js')
       },
@@ -39,7 +39,10 @@ export async function buildClient (ctx: ViteBuildContext) {
       jsxPlugin(),
       createVuePlugin(ctx.config.vue),
       PluginLegacy(),
-      devStyleSSRPlugin(ctx.nuxt.options.rootDir)
+      devStyleSSRPlugin({
+        rootDir: ctx.nuxt.options.rootDir,
+        buildAssetsURL: joinURL(ctx.nuxt.options.app.baseURL, ctx.nuxt.options.app.buildAssetsDir)
+      })
     ],
     server: {
       middlewareMode: true

packages/bridge/src/vite/manifest.ts

@@ -46,7 +46,6 @@ export async function prepareManifests (ctx: ViteBuildContext) {
 export async function generateBuildManifest (ctx: ViteBuildContext) {
   const rDist = (...args: string[]): string => resolve(ctx.nuxt.options.buildDir, 'dist', ...args)
 
-  const publicPath = ctx.nuxt.options.app.assetsPath // Default: /nuxt/
   const viteClientManifest = await fse.readJSON(rDist('client/manifest.json'))
   const clientEntries = Object.entries(viteClientManifest)
 
@@ -59,12 +58,13 @@ export async function generateBuildManifest (ctx: ViteBuildContext) {
   const polyfillName = initialEntries.find(id => id.startsWith('polyfills-legacy.'))
 
   // @vitejs/plugin-legacy uses SystemJS which need to call `System.import` to load modules
-  const clientImports = initialJs.filter(id => id !== polyfillName).map(id => publicPath + id)
+  const clientImports = initialJs.filter(id => id !== polyfillName)
   const clientEntryCode = `var imports = ${JSON.stringify(clientImports)}\nimports.reduce((p, id) => p.then(() => System.import(id)), Promise.resolve())`
   const clientEntryName = 'entry-legacy.' + hash(clientEntryCode) + '.js'
 
   const clientManifest = {
-    publicPath,
+    // This publicPath will be ignored by Nitro and computed dynamically
+    publicPath: ctx.nuxt.options.app.buildAssetsDir,
     all: uniq([
       polyfillName,
       clientEntryName,
@@ -74,12 +74,12 @@ export async function generateBuildManifest (ctx: ViteBuildContext) {
       polyfillName,
       clientEntryName,
       ...initialAssets
-    ],
+    ].filter(Boolean),
     async: [
       // We move initial entries to the client entry
       ...initialJs,
       ...asyncEntries
-    ],
+    ].filter(Boolean),
     modules: {},
     assetsMapping: {}
   }

packages/bridge/src/vite/server.ts

@@ -51,7 +51,6 @@ export async function buildServer (ctx: ViteBuildContext) {
     },
     build: {
       outDir: resolve(ctx.nuxt.options.buildDir, 'dist/server'),
-      assetsDir: ctx.nuxt.options.app.assetsPath.replace(/^\/|\/$/, ''),
       ssr: true,
       ssrManifest: true,
       rollupOptions: {

packages/bridge/src/vite/vite.ts

@@ -1,6 +1,7 @@
 import { resolve } from 'pathe'
 import * as vite from 'vite'
 import consola from 'consola'
+import { withoutLeadingSlash } from 'ufo'
 import { distDir } from '../dirs'
 import { warmupViteServer } from '../../../vite/src/utils/warmup'
 import { buildClient } from './client'
@@ -73,6 +74,7 @@ async function bundle (nuxt: Nuxt, builder: any) {
         publicDir: resolve(nuxt.options.srcDir, nuxt.options.dir.static),
         clearScreen: false,
         build: {
+          assetsDir: withoutLeadingSlash(nuxt.options.app.buildAssetsDir),
           emptyOutDir: false
         },
         plugins: [

packages/nitro/src/build.ts

@@ -4,7 +4,7 @@ import * as rollup from 'rollup'
 import fse from 'fs-extra'
 import { printFSTree } from './utils/tree'
 import { getRollupConfig } from './rollup/config'
-import { hl, prettyPath, serializeTemplate, writeFile, isDirectory, readDirRecursively, replaceAll } from './utils'
+import { hl, prettyPath, serializeTemplate, writeFile, isDirectory, replaceAll } from './utils'
 import { NitroContext } from './context'
 import { scanMiddleware } from './server/middleware'
 
@@ -30,20 +30,17 @@ async function cleanupDir (dir: string) {
 export async function generate (nitroContext: NitroContext) {
   consola.start('Generating public...')
 
+  await nitroContext._internal.hooks.callHook('nitro:generate', nitroContext)
+
   const publicDir = nitroContext._nuxt.publicDir
-  let publicFiles: string[] = []
   if (await isDirectory(publicDir)) {
-    publicFiles = readDirRecursively(publicDir).map(r => r.replace(publicDir, ''))
     await fse.copy(publicDir, nitroContext.output.publicDir)
   }
 
   const clientDist = resolve(nitroContext._nuxt.buildDir, 'dist/client')
   if (await isDirectory(clientDist)) {
-    await fse.copy(clientDist, join(nitroContext.output.publicDir, nitroContext._nuxt.publicPath), {
-      // TODO: Workaround vite's issue that duplicates public files
-      // https://github.com/nuxt/framework/issues/1192
-      filter: src => !publicFiles.includes(src.replace(clientDist, ''))
-    })
+    const buildAssetsDir = join(nitroContext.output.publicDir, nitroContext._nuxt.buildAssetsDir)
+    await fse.copy(clientDist, buildAssetsDir)
   }
 
   consola.success('Generated public ' + prettyPath(nitroContext.output.publicDir))

packages/nitro/src/context.ts

@@ -19,6 +19,7 @@ export interface NitroHooks {
   'nitro:document': (htmlTemplate: { src: string, contents: string, dst: string }) => void
   'nitro:rollup:before': (context: NitroContext) => void | Promise<void>
   'nitro:compiled': (context: NitroContext) => void
+  'nitro:generate': (context: NitroContext) => void | Promise<void>
   'close': () => void
 }
 
@@ -71,8 +72,8 @@ export interface NitroContext {
     generateDir: string
     publicDir: string
     serverDir: string
-    routerBase: string
-    publicPath: string
+    baseURL: string
+    buildAssetsDir: string
     isStatic: boolean
     fullStatic: boolean
     staticAssets: any
@@ -139,8 +140,8 @@ export function getNitroContext (nuxtOptions: NuxtOptions, input: NitroInput): N
       generateDir: nuxtOptions.generate.dir,
       publicDir: resolve(nuxtOptions.srcDir, nuxtOptions.dir.public || nuxtOptions.dir.static),
       serverDir: resolve(nuxtOptions.srcDir, (nuxtOptions.dir as any).server || 'server'),
-      routerBase: nuxtOptions.router.base,
-      publicPath: nuxtOptions.app.assetsPath,
+      baseURL: nuxtOptions.app.baseURL,
+      buildAssetsDir: nuxtOptions.app.buildAssetsDir,
       isStatic: nuxtOptions.target === 'static' && !nuxtOptions.dev,
       fullStatic: nuxtOptions.target === 'static' && !nuxtOptions._legacyGenerate,
       staticAssets: nuxtOptions.generate.staticAssets,

packages/nitro/src/presets/browser.ts

@@ -1,17 +1,19 @@
 import { existsSync, promises as fsp } from 'fs'
 import { resolve } from 'pathe'
 import consola from 'consola'
+import { joinURL } from 'ufo'
 import { extendPreset, prettyPath } from '../utils'
 import { NitroPreset, NitroContext, NitroInput } from '../context'
 import { worker } from './worker'
 
 export const browser: NitroPreset = extendPreset(worker, (input: NitroInput) => {
-  const routerBase = input._nuxt.routerBase
+  // TODO: Join base at runtime
+  const baseURL = input._nuxt.baseURL
 
   const script = `<script>
 if ('serviceWorker' in navigator) {
   window.addEventListener('load', function () {
-    navigator.serviceWorker.register('${routerBase}sw.js');
+    navigator.serviceWorker.register('${joinURL(baseURL, 'sw.js')}');
   });
 }
 </script>`
@@ -21,11 +23,11 @@ if ('serviceWorker' in navigator) {
 <html>
 <head>
   <meta charset="utf-8">
-  <link rel="prefetch" href="${routerBase}sw.js">
-  <link rel="prefetch" href="${routerBase}_server/index.mjs">
+  <link rel="prefetch" href="${joinURL(baseURL, 'sw.js')}">
+  <link rel="prefetch" href="${joinURL(baseURL, '_server/index.mjs')}">
   <script>
   async function register () {
-    const registration = await navigator.serviceWorker.register('${routerBase}sw.js')
+    const registration = await navigator.serviceWorker.register('${joinURL(baseURL, 'sw.js')}')
     await navigator.serviceWorker.ready
     registration.active.addEventListener('statechange', (event) => {
       if (event.target.state === 'activated') {
@@ -62,7 +64,7 @@ if ('serviceWorker' in navigator) {
         tmpl.contents = tmpl.contents.replace('</body>', script + '</body>')
       },
       async 'nitro:compiled' ({ output }: NitroContext) {
-        await fsp.writeFile(resolve(output.publicDir, 'sw.js'), `self.importScripts('${input._nuxt.routerBase}_server/index.mjs');`, 'utf8')
+        await fsp.writeFile(resolve(output.publicDir, 'sw.js'), `self.importScripts('${joinURL(baseURL, '_server/index.mjs')}');`, 'utf8')
 
         // Temp fix
         if (!existsSync(resolve(output.publicDir, 'index.html'))) {

packages/nitro/src/rollup/config.ts

@@ -159,8 +159,6 @@ export const getRollupConfig = (nitroContext: NitroContext) => {
       'process.server': 'true',
       'process.client': 'false',
       'process.env.NUXT_NO_SSR': JSON.stringify(!nitroContext._nuxt.ssr),
-      'process.env.ROUTER_BASE': JSON.stringify(nitroContext._nuxt.routerBase),
-      'process.env.PUBLIC_PATH': JSON.stringify(nitroContext._nuxt.publicPath),
       'process.env.NUXT_STATIC_BASE': JSON.stringify(nitroContext._nuxt.staticAssets.base),
       'process.env.NUXT_STATIC_VERSION': JSON.stringify(nitroContext._nuxt.staticAssets.version),
       'process.env.NUXT_FULL_STATIC': nitroContext._nuxt.fullStatic as unknown as string,
@@ -227,6 +225,7 @@ export const getRollupConfig = (nitroContext: NitroContext) => {
     entries: {
       '#nitro': nitroContext._internal.runtimeDir,
       '#nitro-renderer': resolve(nitroContext._internal.runtimeDir, 'app', renderer),
+      '#paths': resolve(nitroContext._internal.runtimeDir, 'app/paths'),
       '#config': resolve(nitroContext._internal.runtimeDir, 'app/config'),
       '#nitro-vue-renderer': vue2ServerRenderer,
       // Only file and data URLs are supported by the default ESM loader on Windows (#427)

packages/nitro/src/runtime/app/config.ts

@@ -11,6 +11,12 @@ for (const type of ['private', 'public']) {
   }
 }
 
+// Load dynamic app configuration
+const appConfig = _runtimeConfig.public.app
+appConfig.baseURL = process.env.NUXT_APP_BASE_URL || appConfig.baseURL
+appConfig.cdnURL = process.env.NUXT_APP_CDN_URL || appConfig.cdnURL
+appConfig.buildAssetsDir = process.env.NUXT_APP_BUILD_ASSETS_DIR || appConfig.buildAssetsDir
+
 // Named exports
 export const privateConfig = deepFreeze(defu(_runtimeConfig.private, _runtimeConfig.public))
 export const publicConfig = deepFreeze(_runtimeConfig.public)

packages/nitro/src/runtime/app/paths.ts

@@ -0,0 +1,19 @@
+import { joinURL } from 'ufo'
+import config from '#config'
+
+export function baseURL () {
+  return config.app.baseURL
+}
+
+export function buildAssetsDir () {
+  return config.app.buildAssetsDir
+}
+
+export function buildAssetsURL (...path: string[]) {
+  return joinURL(publicAssetsURL(), config.app.buildAssetsDir, ...path)
+}
+
+export function publicAssetsURL (...path: string[]) {
+  const publicBase = config.app.cdnURL || config.app.baseURL
+  return path.length ? joinURL(publicBase, ...path) : publicBase
+}

packages/nitro/src/runtime/app/render.ts

@@ -2,6 +2,7 @@ import type { ServerResponse } from 'http'
 import { createRenderer } from 'vue-bundle-renderer'
 import devalue from '@nuxt/devalue'
 import { privateConfig, publicConfig } from './config'
+import { buildAssetsURL } from './paths'
 // @ts-ignore
 import htmlTemplate from '#build/views/document.template.mjs'
 
@@ -12,8 +13,6 @@ const PAYLOAD_JS = '/payload.js'
 const getClientManifest = cachedImport(() => import('#build/dist/server/client.manifest.mjs'))
 const getSSRApp = !process.env.NUXT_NO_SSR && cachedImport(() => import('#build/dist/server/server.mjs'))
 
-const publicPath = (publicConfig.app && publicConfig.app.assetsPath) || process.env.PUBLIC_PATH || '/_nuxt'
-
 const getSSRRenderer = cachedResult(async () => {
   // Load client manifest
   const clientManifest = await getClientManifest()
@@ -23,7 +22,7 @@ const getSSRRenderer = cachedResult(async () => {
   if (!createSSRApp) { throw new Error('Server bundle is not available') }
   // Create renderer
   const { renderToString } = await import('#nitro-renderer')
-  return createRenderer((createSSRApp), { clientManifest, renderToString, publicPath }).renderToString
+  return createRenderer((createSSRApp), { clientManifest, renderToString, publicPath: buildAssetsURL() }).renderToString
 })
 
 const getSPARenderer = cachedResult(async () => {
@@ -50,13 +49,13 @@ const getSPARenderer = cachedResult(async () => {
         entryFiles
           .flatMap(({ css }) => css)
           .filter(css => css != null)
-          .map(file => `<link rel="stylesheet" href="${publicPath}${file}">`)
+          .map(file => `<link rel="stylesheet" href="${buildAssetsURL(file)}">`)
           .join(''),
       renderScripts: () =>
         entryFiles
           .map(({ file }) => {
             const isMJS = !file.endsWith('.js')
-            return `<script ${isMJS ? 'type="module"' : ''} src="${publicPath}${file}"></script>`
+            return `<script ${isMJS ? 'type="module"' : ''} src="${buildAssetsURL(file)}"></script>`
           })
           .join('')
     }

packages/nitro/src/runtime/entries/cloudflare.ts

@@ -1,9 +1,9 @@
 import '#polyfill'
-import { getAssetFromKV } from '@cloudflare/kv-asset-handler'
+import { getAssetFromKV, mapRequestToAsset } from '@cloudflare/kv-asset-handler'
+import { withoutBase } from 'ufo'
 import { localCall } from '../server'
 import { requestHasBody, useRequestBody } from '../server/utils'
-
-const PUBLIC_PATH = process.env.PUBLIC_PATH // Default: /_nuxt/
+import { buildAssetsURL, baseURL } from '#paths'
 
 addEventListener('fetch', (event: any) => {
   event.respondWith(handleEvent(event))
@@ -11,7 +11,7 @@ addEventListener('fetch', (event: any) => {
 
 async function handleEvent (event) {
   try {
-    return await getAssetFromKV(event, { cacheControl: assetsCacheControl })
+    return await getAssetFromKV(event, { cacheControl: assetsCacheControl, mapRequestToAsset: baseURLModifier })
   } catch (_err) {
     // Ignore
   }
@@ -42,7 +42,7 @@ async function handleEvent (event) {
 }
 
 function assetsCacheControl (request) {
-  if (request.url.includes(PUBLIC_PATH) /* TODO: Check with routerBase */) {
+  if (request.url.startsWith(buildAssetsURL())) {
     return {
       browserTTL: 31536000,
       edgeTTL: 31536000
@@ -50,3 +50,8 @@ function assetsCacheControl (request) {
   }
   return {}
 }
+
+const baseURLModifier = (request: Request) => {
+  const url = withoutBase(request.url, baseURL())
+  return mapRequestToAsset(new Request(url, request))
+}

packages/nitro/src/runtime/entries/server.ts

@@ -3,6 +3,7 @@ import { Server as HttpServer } from 'http'
 import { Server as HttpsServer } from 'https'
 import destr from 'destr'
 import { handle } from '../server'
+import { baseURL } from '#paths'
 
 const cert = process.env.NITRO_SSL_CERT
 const key = process.env.NITRO_SSL_KEY
@@ -19,7 +20,7 @@ server.listen(port, hostname, (err) => {
     process.exit(1)
   }
   const protocol = cert && key ? 'https' : 'http'
-  console.log(`Listening on ${protocol}://${hostname}:${port}`)
+  console.log(`Listening on ${protocol}://${hostname}:${port}${baseURL()}`)
 })
 
 export default {}

packages/nitro/src/runtime/server/index.ts

@@ -1,8 +1,8 @@
-import '../app/config'
 import { createApp, useBase } from 'h3'
 import { createFetch, Headers } from 'ohmyfetch'
 import destr from 'destr'
 import { createCall, createFetch as createLocalFetch } from 'unenv/runtime/fetch/index'
+import { baseURL } from '../app/paths'
 import { timingMiddleware } from './timing'
 import { handleError } from './error'
 // @ts-ignore
@@ -18,7 +18,7 @@ app.use(serverMiddleware)
 app.use(() => import('../app/render').then(e => e.renderMiddleware), { lazy: true })
 
 export const stack = app.stack
-export const handle = useBase(process.env.ROUTER_BASE, app)
+export const handle = useBase(baseURL(), app)
 export const localCall = createCall(handle)
 export const localFetch = createLocalFetch(localCall, globalThis.fetch)
 

packages/nitro/src/runtime/server/static.ts

@@ -2,9 +2,10 @@ import { createError } from 'h3'
 import { withoutTrailingSlash, withLeadingSlash, parseURL } from 'ufo'
 // @ts-ignore
 import { getAsset, readAsset } from '#static'
+import { buildAssetsDir } from '#paths'
 
 const METHODS = ['HEAD', 'GET']
-const PUBLIC_PATH = process.env.PUBLIC_PATH // Default: /_nuxt/
+
 const TWO_DAYS = 2 * 60 * 60 * 24
 const STATIC_ASSETS_BASE = process.env.NUXT_STATIC_BASE + '/' + process.env.NUXT_STATIC_VERSION
 
@@ -26,8 +27,10 @@ export default async function serveStatic (req, res) {
     }
   }
 
+  const isBuildAsset = id.startsWith(buildAssetsDir())
+
   if (!asset) {
-    if (id.startsWith(PUBLIC_PATH) && !id.startsWith(STATIC_ASSETS_BASE)) {
+    if (isBuildAsset && !id.startsWith(STATIC_ASSETS_BASE)) {
       throw createError({
         statusMessage: 'Cannot find static asset ' + id,
         statusCode: 404
@@ -62,7 +65,7 @@ export default async function serveStatic (req, res) {
     res.setHeader('Last-Modified', asset.mtime)
   }
 
-  if (id.startsWith(PUBLIC_PATH)) {
+  if (isBuildAsset) {
     res.setHeader('Cache-Control', `max-age=${TWO_DAYS}, immutable`)
   }
 

packages/nitro/src/server/dev.ts

@@ -12,6 +12,7 @@ import servePlaceholder from 'serve-placeholder'
 import serveStatic from 'serve-static'
 import { resolve } from 'pathe'
 import connect from 'connect'
+import { joinURL } from 'ufo'
 import type { NitroContext } from '../context'
 import { handleVfs } from './vfs'
 
@@ -76,8 +77,9 @@ export function createDevServer (nitroContext: NitroContext) {
   const app = createApp()
 
   // _nuxt and static
-  app.use(nitroContext._nuxt.publicPath, serveStatic(resolve(nitroContext._nuxt.buildDir, 'dist/client')))
-  app.use(nitroContext._nuxt.routerBase, serveStatic(resolve(nitroContext._nuxt.publicDir)))
+  const buildAssetsURL = joinURL(nitroContext._nuxt.baseURL, nitroContext._nuxt.buildAssetsDir)
+  app.use(buildAssetsURL, serveStatic(resolve(nitroContext._nuxt.buildDir, 'dist/client')))
+  app.use(nitroContext._nuxt.baseURL, serveStatic(resolve(nitroContext._nuxt.publicDir)))
 
   // debugging endpoint to view vfs
   app.use('/_vfs', useBase('/_vfs', handleVfs(nitroContext)))
@@ -89,7 +91,7 @@ export function createDevServer (nitroContext: NitroContext) {
   app.use(devMiddleware.middleware)
 
   // serve placeholder 404 assets instead of hitting SSR
-  app.use(nitroContext._nuxt.publicPath, servePlaceholder())
+  app.use(buildAssetsURL, servePlaceholder())
 
   // SSR Proxy
   const proxy = httpProxy.createProxy()

packages/nitro/src/server/middleware.ts

@@ -23,10 +23,10 @@ export interface ServerMiddleware {
   promisify?: boolean // Default is true
 }
 
-function filesToMiddleware (files: string[], baseDir: string, basePath: string, overrides?: Partial<ServerMiddleware>): ServerMiddleware[] {
+function filesToMiddleware (files: string[], baseDir: string, baseURL: string, overrides?: Partial<ServerMiddleware>): ServerMiddleware[] {
   return files.map((file) => {
     const route = joinURL(
-      basePath,
+      baseURL,
       file
         .slice(0, file.length - extname(file).length)
         .replace(/\/index$/, '')

packages/nitro/src/utils/index.ts

@@ -1,5 +1,5 @@
 import { createRequire } from 'module'
-import { relative, dirname, join, resolve } from 'pathe'
+import { relative, dirname, resolve } from 'pathe'
 import fse from 'fs-extra'
 import jiti from 'jiti'
 import defu from 'defu'
@@ -152,11 +152,3 @@ export function readPackageJson (
     throw error
   }
 }
-
-export function readDirRecursively (dir: string) {
-  return fse.readdirSync(dir).reduce((files, file) => {
-    const name = join(dir, file)
-    const isDirectory = fse.statSync(name).isDirectory()
-    return isDirectory ? [...files, ...readDirRecursively(name)] : [...files, name]
-  }, [])
-}

packages/nitro/types/shims.d.ts

@@ -21,3 +21,11 @@ declare module '#config' {
   const runtimeConfig: PrivateRuntimeConfig & PublicRuntimeConfig
   export default runtimeConfig
 }
+
+declare module '#paths' {
+  export const baseURL: () => string
+  export const buildAssetsDir: () => string
+
+  export const buildAssetsURL: (...path: string[]) => string
+  export const publicAssetsURL: (...path: string[]) => string
+}

packages/nuxt3/src/core/nitro.ts

@@ -20,6 +20,7 @@ export function initNitro (nuxt: Nuxt) {
   nuxt.hooks.addHooks(nitroContext.nuxtHooks)
   nuxt.hook('close', () => nitroContext._internal.hooks.callHook('close'))
   nitroContext._internal.hooks.hook('nitro:document', template => nuxt.callHook('nitro:document', template))
+  nitroContext._internal.hooks.hook('nitro:generate', ctx => nuxt.callHook('nitro:generate', ctx))
 
   // @ts-ignore
   nuxt.hooks.addHooks(nitroDevContext.nuxtHooks)

packages/nuxt3/src/pages/runtime/router.ts

@@ -8,7 +8,7 @@ import {
 import NuxtNestedPage from './nested-page.vue'
 import NuxtPage from './page.vue'
 import NuxtLayout from './layout'
-import { defineNuxtPlugin } from '#app'
+import { defineNuxtPlugin, useRuntimeConfig } from '#app'
 // @ts-ignore
 import routes from '#build/routes'
 
@@ -29,9 +29,10 @@ export default defineNuxtPlugin((nuxtApp) => {
   // TODO: remove before release - present for backwards compatibility & intentionally undocumented
   nuxtApp.vueApp.component('NuxtChild', NuxtNestedPage)
 
+  const { baseURL } = useRuntimeConfig().app
   const routerHistory = process.client
-    ? createWebHistory()
-    : createMemoryHistory()
+    ? createWebHistory(baseURL)
+    : createMemoryHistory(baseURL)
 
   const router = createRouter({
     history: routerHistory,

packages/schema/src/config/_app.ts

@@ -1,7 +1,6 @@
 import { resolve, join } from 'pathe'
 import { existsSync, readdirSync } from 'fs'
 import defu from 'defu'
-import { isRelative, joinURL, hasProtocol } from 'ufo'
 
 export default {
   /** Vue.js config */
@@ -29,16 +28,40 @@ export default {
   /**
    * Nuxt App configuration.
    * @version 2
+   * @version 3
    */
   app: {
-    $resolve: (val, get) => {
-      const useCDN = hasProtocol(get('build.publicPath'), true) && !get('dev')
-      const isRelativePublicPath = isRelative(get('build.publicPath'))
-      return defu(val, {
-        basePath: get('router.base'),
-        assetsPath: isRelativePublicPath ? get('build.publicPath') : useCDN ? '/' : joinURL(get('router.base'), get('build.publicPath')),
-        cdnURL: useCDN ? get('build.publicPath') : null
-      })
+    /**
+     * The base path of your Nuxt application.
+     *
+     * This can be set at runtime by setting the BASE_PATH environment variable.
+     * @example
+     * ```bash
+     * BASE_PATH=/prefix/ node .output/server/index.mjs
+     * ```
+     */
+    baseURL: '/',
+    /** The folder name for the built site assets, relative to `baseURL` (or `cdnURL` if set). This is set at build time and should not be customized at runtime. */
+    buildAssetsDir: '/_nuxt/',
+    /**
+     * The folder name for the built site assets, relative to `baseURL` (or `cdnURL` if set).
+     * @deprecated - use `buildAssetsDir` instead
+     * @version 2
+     */
+    assetsPath: {
+      $resolve: (val, get) => val ?? get('buildAssetsDir')
+    },
+    /**
+     * An absolute URL to serve the public folder from (production-only).
+     *
+     * This can be set to a different value at runtime by setting the CDN_URL environment variable.
+     * @example
+     * ```bash
+     * CDN_URL=https://mycdn.org/ node .output/server/index.mjs
+     * ```
+    */
+    cdnURL: {
+      $resolve: (val, get) => get('dev') ? null : val || null
     }
   },
 
@@ -302,7 +325,7 @@ export default {
    * @see [vue@3 documentation](https://v3.vuejs.org/guide/transitions-enterleave.html)
    * @version 2
    */
-   pageTransition: {
+  pageTransition: {
     $resolve: (val, get) => {
       val = typeof val === 'string' ? { name: val } : val
       return defu(val, {

packages/schema/src/config/build.ts

@@ -1,5 +1,5 @@
 import { isCI, isTest } from 'std-env'
-import { hasProtocol } from 'ufo'
+import { normalizeURL, withTrailingSlash } from 'ufo'
 
 export default {
   /**
@@ -153,13 +153,9 @@ export default {
    * }
    * ```
    * @version 2
-   * @version 3
    */
   publicPath: {
-    $resolve: (val, get) => {
-      if (hasProtocol(val, true) && get('dev')) { val = null }
-      return (val || '/_nuxt/').replace(/([^/])$/, '$1/')
-    }
+    $resolve: (val, get) => val ? withTrailingSlash(normalizeURL(val)) : get('app.buildAssetsDir')
   },
 
   /**

packages/schema/src/config/generate.ts

@@ -160,7 +160,7 @@ export default {
      * The full path to the directory underneath `/_nuxt/` where static assets
      * (payload, state and manifest files) will live.
      */
-    base: { $resolve: (val, get) => val || joinURL(get('app.assetsPath'), get('generate.dir')) },
+    base: { $resolve: (val, get) => val || joinURL(get('app.buildAssetsDir'), get('generate.dir')) },
     /** The full path to the versioned directory where static assets for the current buidl are located. */
     versionBase: { $resolve: (val, get) => val || joinURL(get('generate.base'), get('generate.version')) },
     /** A unique string to uniquely identify payload versions (defaults to the current timestamp).  */

packages/schema/src/config/router.ts

@@ -16,10 +16,9 @@ export default {
    * This can be useful if you need to serve Nuxt as a different context root, from
    * within a bigger web site.
    * @version 2
-   * @version 3
    */
   base: {
-    $resolve: (val = '/') => withTrailingSlash(normalizeURL(val))
+    $resolve: (val, get) => val ? withTrailingSlash(normalizeURL(val)) : get('app.baseURL')
   },
 
   /** @private */

packages/schema/src/types/hooks.ts

@@ -80,6 +80,7 @@ export interface NuxtHooks {
   // @nuxt/nitro
   'nitro:document': (template: { src: string, contents: string }) => HookResult
   'nitro:context': (context: any) => HookResult
+  'nitro:generate': (context: any) => HookResult
 
   // @nuxt/cli
   'generate:cache:ignore': (ignore: string[]) => HookResult

packages/vite/src/client.ts

@@ -5,12 +5,14 @@ import vuePlugin from '@vitejs/plugin-vue'
 import viteJsxPlugin from '@vitejs/plugin-vue-jsx'
 import type { Connect } from 'vite'
 
+import { joinURL, withoutLeadingSlash } from 'ufo'
 import { cacheDirPlugin } from './plugins/cache-dir'
 import { analyzePlugin } from './plugins/analyze'
 import { wpfs } from './utils/wpfs'
 import type { ViteBuildContext, ViteOptions } from './vite'
 import { writeManifest } from './manifest'
 import { devStyleSSRPlugin } from './plugins/dev-ssr-css'
+import { DynamicBasePlugin } from './plugins/dynamic-base'
 
 export async function buildClient (ctx: ViteBuildContext) {
   const clientConfig: vite.InlineConfig = vite.mergeConfig(ctx.config, {
@@ -25,6 +27,7 @@ export async function buildClient (ctx: ViteBuildContext) {
       }
     },
     build: {
+      assetsDir: ctx.nuxt.options.dev ? withoutLeadingSlash(ctx.nuxt.options.app.buildAssetsDir) : '.',
       rollupOptions: {
         output: {
           chunkFileNames: ctx.nuxt.options.dev ? undefined : '[name]-[hash].mjs',
@@ -38,7 +41,11 @@ export async function buildClient (ctx: ViteBuildContext) {
       cacheDirPlugin(ctx.nuxt.options.rootDir, 'client'),
       vuePlugin(ctx.config.vue),
       viteJsxPlugin(),
-      devStyleSSRPlugin(ctx.nuxt.options.rootDir)
+      DynamicBasePlugin.vite({ env: 'client', devAppConfig: ctx.nuxt.options.app }),
+      devStyleSSRPlugin({
+        rootDir: ctx.nuxt.options.rootDir,
+        buildAssetsURL: joinURL(ctx.nuxt.options.app.baseURL, ctx.nuxt.options.app.buildAssetsDir)
+      })
     ],
     server: {
       middlewareMode: true

packages/vite/src/manifest.ts

@@ -1,5 +1,6 @@
 import fse from 'fs-extra'
 import { resolve } from 'pathe'
+import { joinURL } from 'ufo'
 import type { ViteBuildContext } from './vite'
 
 export async function writeManifest (ctx: ViteBuildContext, extraEntries: string[] = []) {
@@ -15,7 +16,7 @@ export async function writeManifest (ctx: ViteBuildContext, extraEntries: string
 
   // Legacy dev manifest
   const devClientManifest = {
-    publicPath: ctx.nuxt.options.build.publicPath,
+    publicPath: joinURL(ctx.nuxt.options.app.baseURL, ctx.nuxt.options.app.buildAssetsDir),
     all: entries,
     initial: entries,
     async: [],

packages/vite/src/plugins/dev-ssr-css.ts

@@ -1,7 +1,13 @@
+import { joinURL } from 'ufo'
 import { Plugin } from 'vite'
 import { isCSS } from '../utils'
 
-export function devStyleSSRPlugin (rootDir: string): Plugin {
+export interface DevStyleSSRPluginOptions {
+  rootDir: string
+  buildAssetsURL: string
+}
+
+export function devStyleSSRPlugin (options: DevStyleSSRPluginOptions): Plugin {
   return {
     name: 'nuxt:dev-style-ssr',
     apply: 'serve',
@@ -12,13 +18,13 @@ export function devStyleSSRPlugin (rootDir: string): Plugin {
       }
 
       let moduleId = id
-      if (moduleId.startsWith(rootDir)) {
-        moduleId = moduleId.slice(rootDir.length)
+      if (moduleId.startsWith(options.rootDir)) {
+        moduleId = moduleId.slice(options.rootDir.length)
       }
 
       // When dev `<style>` is injected, remove the `<link>` styles from manifest
-      // TODO: Use `app.assetsPath` or unique hash
-      return code + `\ndocument.querySelectorAll(\`link[href="/_nuxt${moduleId}"]\`).forEach(i=>i.remove())`
+      const selector = joinURL(options.buildAssetsURL, moduleId)
+      return code + `\ndocument.querySelectorAll(\`link[href="${selector}"]\`).forEach(i=>i.remove())`
     }
   }
 }

packages/vite/src/plugins/dynamic-base.ts

@@ -0,0 +1,57 @@
+import { createUnplugin } from 'unplugin'
+
+interface DynamicBasePluginOptions {
+  env: 'dev' | 'server' | 'client'
+  devAppConfig?: Record<string, any>
+  globalPublicPath?: string
+}
+
+export const DynamicBasePlugin = createUnplugin(function (options: DynamicBasePluginOptions) {
+  return {
+    name: 'nuxt:dynamic-base-path',
+    resolveId (id) {
+      if (id.startsWith('/__NUXT_BASE__')) {
+        return id.replace('/__NUXT_BASE__', '')
+      }
+    },
+    enforce: 'post',
+    transform (code, id) {
+      if (options.globalPublicPath && id.includes('entry.ts')) {
+        code = 'import { joinURL } from "ufo";' +
+          `${options.globalPublicPath} = joinURL(NUXT_BASE, NUXT_CONFIG.app.buildAssetsDir);` + code
+      }
+
+      if (code.includes('NUXT_BASE') && !code.includes('const NUXT_BASE =')) {
+        code = 'const NUXT_BASE = NUXT_CONFIG.app.cdnURL || NUXT_CONFIG.app.baseURL;' + code
+
+        if (options.env === 'dev') {
+          code = `const NUXT_CONFIG = { app: ${JSON.stringify(options.devAppConfig)} };` + code
+        } else if (options.env === 'server') {
+          code = 'import NUXT_CONFIG from "#config";' + code
+        } else {
+          code = 'const NUXT_CONFIG = __NUXT__.config;' + code
+        }
+      }
+
+      if (id === 'vite/preload-helper') {
+        // Define vite base path as buildAssetsUrl (i.e. including _nuxt/)
+        code = code.replace(
+          /const base = ['"]\/__NUXT_BASE__\/['"]/,
+          'import { joinURL } from "ufo";' +
+          'const base = joinURL(NUXT_BASE, NUXT_CONFIG.app.buildAssetsDir);')
+      }
+
+      // Sanitize imports
+      code = code.replace(/from *['"]\/__NUXT_BASE__(\/[^'"]*)['"]/g, 'from "$1"')
+
+      // Dynamically compute string URLs featuring baseURL
+      for (const delimiter of ['`', '"', "'"]) {
+        const delimiterRE = new RegExp(`${delimiter}([^${delimiter}]*)\\/__NUXT_BASE__\\/([^${delimiter}]*)${delimiter}`, 'g')
+        /* eslint-disable-next-line no-template-curly-in-string */
+        code = code.replace(delimiterRE, '`$1${NUXT_BASE}$2`')
+      }
+
+      return code
+    }
+  }
+})

packages/vite/src/server.ts

@@ -1,4 +1,4 @@
-import { resolve, normalize } from 'pathe'
+import { join, resolve, normalize } from 'pathe'
 import * as vite from 'vite'
 import vuePlugin from '@vitejs/plugin-vue'
 import viteJsxPlugin from '@vitejs/plugin-vue-jsx'
@@ -6,12 +6,14 @@ import fse from 'fs-extra'
 import pDebounce from 'p-debounce'
 import consola from 'consola'
 import { resolveModule } from '@nuxt/kit'
+import { withoutTrailingSlash } from 'ufo'
 import { ViteBuildContext, ViteOptions } from './vite'
 import { wpfs } from './utils/wpfs'
 import { cacheDirPlugin } from './plugins/cache-dir'
+import { DynamicBasePlugin } from './plugins/dynamic-base'
 import { bundleRequest } from './dev-bundler'
 import { writeManifest } from './manifest'
-import { isCSS } from './utils'
+import { isCSS, isDirectory, readDirRecursively } from './utils'
 
 export async function buildServer (ctx: ViteBuildContext) {
   const _resolve = id => resolveModule(id, { paths: ctx.nuxt.options.modulesDir })
@@ -38,7 +40,7 @@ export async function buildServer (ctx: ViteBuildContext) {
       }
     },
     ssr: {
-      external: [],
+      external: ['#config'],
       noExternal: [
         ...ctx.nuxt.options.build.transpile,
         // TODO: Use externality for production (rollup) build
@@ -75,12 +77,41 @@ export async function buildServer (ctx: ViteBuildContext) {
     plugins: [
       cacheDirPlugin(ctx.nuxt.options.rootDir, 'server'),
       vuePlugin(ctx.config.vue),
+      DynamicBasePlugin.vite({ env: ctx.nuxt.options.dev ? 'dev' : 'server', devAppConfig: ctx.nuxt.options.app }),
       viteJsxPlugin()
     ]
   } as ViteOptions)
 
   await ctx.nuxt.callHook('vite:extendConfig', serverConfig, { isClient: false, isServer: true })
 
+  ctx.nuxt.hook('nitro:generate', async () => {
+    const clientDist = resolve(ctx.nuxt.options.buildDir, 'dist/client')
+
+    // Remove public files that have been duplicated into buildAssetsDir
+    // TODO: Add option to configure this behaviour in vite
+    const publicDir = join(ctx.nuxt.options.srcDir, ctx.nuxt.options.dir.public)
+    let publicFiles: string[] = []
+    if (await isDirectory(publicDir)) {
+      publicFiles = readDirRecursively(publicDir).map(r => r.replace(publicDir, ''))
+      for (const file of publicFiles) {
+        try {
+          fse.rmSync(join(clientDist, file))
+        } catch {}
+      }
+    }
+
+    // Copy doubly-nested /_nuxt/_nuxt files into buildAssetsDir
+    // TODO: Workaround vite issue
+    if (await isDirectory(clientDist)) {
+      const nestedAssetsPath = withoutTrailingSlash(join(clientDist, ctx.nuxt.options.app.buildAssetsDir))
+
+      if (await isDirectory(nestedAssetsPath)) {
+        await fse.copy(nestedAssetsPath, clientDist, { recursive: true })
+        await fse.remove(nestedAssetsPath)
+      }
+    }
+  })
+
   const onBuild = () => ctx.nuxt.callHook('build:resources', wpfs)
 
   // Production build

packages/vite/src/utils/index.ts

@@ -1,4 +1,6 @@
 import { createHash } from 'crypto'
+import { promises as fsp, readdirSync, statSync } from 'fs'
+import { join } from 'pathe'
 
 export function uniq<T> (arr: T[]): T[] {
   return Array.from(new Set(arr))
@@ -32,3 +34,19 @@ export function hash (input: string, length = 8) {
     .digest('hex')
     .slice(0, length)
 }
+
+export function readDirRecursively (dir: string) {
+  return readdirSync(dir).reduce((files, file) => {
+    const name = join(dir, file)
+    const isDirectory = statSync(name).isDirectory()
+    return isDirectory ? [...files, ...readDirRecursively(name)] : [...files, name]
+  }, [])
+}
+
+export async function isDirectory (path: string) {
+  try {
+    return (await fsp.stat(path)).isDirectory()
+  } catch (_err) {
+    return false
+  }
+}

packages/vite/src/vite.ts

@@ -5,6 +5,7 @@ import type { Nuxt } from '@nuxt/schema'
 import type { InlineConfig, SSROptions } from 'vite'
 import type { Options } from '@vitejs/plugin-vue'
 import { sanitizeFilePath } from 'mlly'
+import { joinURL, withoutLeadingSlash } from 'ufo'
 import { buildClient } from './client'
 import { buildServer } from './server'
 import virtual from './plugins/virtual'
@@ -47,7 +48,9 @@ export async function bundle (nuxt: Nuxt) {
             'abort-controller': 'unenv/runtime/mock/empty'
           }
         },
-        base: nuxt.options.build.publicPath,
+        base: nuxt.options.dev
+          ? joinURL(nuxt.options.app.baseURL, nuxt.options.app.buildAssetsDir)
+          : '/__NUXT_BASE__/',
         publicDir: resolve(nuxt.options.srcDir, nuxt.options.dir.public),
         // TODO: move to kit schema when it exists
         vue: {
@@ -71,6 +74,7 @@ export async function bundle (nuxt: Nuxt) {
         },
         clearScreen: false,
         build: {
+          assetsDir: withoutLeadingSlash(nuxt.options.app.buildAssetsDir),
           emptyOutDir: false,
           rollupOptions: {
             input: resolve(nuxt.options.appDir, 'entry'),

packages/webpack/src/configs/client.ts

@@ -4,6 +4,7 @@ import webpack from 'webpack'
 import { BundleAnalyzerPlugin } from 'webpack-bundle-analyzer'
 
 import type { ClientOptions } from 'webpack-hot-middleware'
+import { joinURL } from 'ufo'
 import { applyPresets, WebpackConfigContext } from '../utils/config'
 import { nuxt } from '../presets/nuxt'
 
@@ -53,7 +54,7 @@ function clientHMR (ctx: WebpackConfigContext) {
   const hotMiddlewareClientOptions = {
     reload: true,
     timeout: 30000,
-    path: `${options.router.base}/__webpack_hmr/${ctx.name}`.replace(/\/\//g, '/'),
+    path: joinURL(options.app.baseURL, '__webpack_hmr', ctx.name),
     ...clientOptions,
     ansiColors: JSON.stringify(clientOptions.ansiColors || {}),
     overlayStyles: JSON.stringify(clientOptions.overlayStyles || {}),

packages/webpack/src/configs/server.ts

@@ -45,9 +45,13 @@ function serverStandalone (ctx: WebpackConfigContext) {
     '#',
     ...ctx.options.build.transpile
   ]
+  const external = ['#config']
 
   if (!Array.isArray(ctx.config.externals)) { return }
   ctx.config.externals.push(({ request }, cb) => {
+    if (external.includes(request)) {
+      return cb(null, true)
+    }
     if (
       request[0] === '.' ||
       isAbsolute(request) ||

packages/webpack/src/presets/base.ts

@@ -5,7 +5,7 @@ import consola from 'consola'
 import webpack from 'webpack'
 import FriendlyErrorsWebpackPlugin from '@nuxt/friendly-errors-webpack-plugin'
 import { escapeRegExp } from 'lodash-es'
-import { hasProtocol, joinURL } from 'ufo'
+import { joinURL } from 'ufo'
 import WarningIgnorePlugin from '../plugins/warning-ignore'
 import { WebpackConfigContext, applyPresets, fileName } from '../utils/config'
 
@@ -194,9 +194,7 @@ function getOutput (ctx: WebpackConfigContext): webpack.Configuration['output']
     path: resolve(options.buildDir, 'dist', ctx.isServer ? 'server' : 'client'),
     filename: fileName(ctx, 'app'),
     chunkFilename: fileName(ctx, 'chunk'),
-    publicPath: hasProtocol(options.build.publicPath, true)
-      ? options.build.publicPath
-      : joinURL(options.router.base, options.build.publicPath)
+    publicPath: joinURL(options.app.baseURL, options.app.buildAssetsDir)
   }
 }
 

packages/webpack/src/webpack.ts

@@ -13,6 +13,8 @@ import type { Context as WebpackDevMiddlewareContext, Options as WebpackDevMiddl
 import type { MiddlewareOptions as WebpackHotMiddlewareOptions } from 'webpack-hot-middleware'
 
 import type { Nuxt } from '@nuxt/schema'
+import { joinURL } from 'ufo'
+import { DynamicBasePlugin } from '../../vite/src/plugins/dynamic-base'
 import { createMFS } from './utils/mfs'
 import { client, server } from './configs'
 import { createWebpackConfigContext, applyPresets, getWebpackConfig } from './utils/config'
@@ -113,6 +115,11 @@ class WebpackBundler {
     this.compilers = webpackConfigs.map((config) => {
       // Support virtual modules (input)
       config.plugins.push(this.virtualModules)
+      config.plugins.push(DynamicBasePlugin.webpack({
+        env: this.nuxt.options.dev ? 'dev' : config.name as 'client',
+        devAppConfig: this.nuxt.options.app,
+        globalPublicPath: '__webpack_public_path__'
+      }))
 
       // Create compiler
       const compiler = webpack(config)
@@ -210,7 +217,7 @@ class WebpackBundler {
         // @ts-ignore
         compiler,
         {
-          publicPath: buildOptions.publicPath,
+          publicPath: joinURL(this.nuxt.options.app.baseURL, this.nuxt.options.app.buildAssetsDir),
           outputFileSystem: this.mfs,
           stats: 'none',
           ...buildOptions.devMiddleware
@@ -229,7 +236,7 @@ class WebpackBundler {
         {
           log: false,
           heartbeat: 10000,
-          path: `/__webpack_hmr/${name}`,
+          path: joinURL(this.nuxt.options.app.baseURL, '__webpack_hmr', name),
           ...hotMiddlewareOptions
         } as WebpackHotMiddlewareOptions
       )