feat: client mode modern and support dev/generate (#4264)

packages/cli/src/commands/build.js

@@ -24,17 +24,6 @@ export default {
       default: true,
       description: 'Don\'t generate static version for SPA mode (useful for nuxt start)'
     },
-    modern: {
-      alias: 'm',
-      type: 'boolean',
-      description: 'Build app for modern browsers',
-      prepare(cmd, options, argv) {
-        options.build = options.build || {}
-        if (argv.modern) {
-          options.build.modern = !!argv.modern
-        }
-      }
-    },
     quiet: {
       alias: 'q',
       type: 'boolean',

packages/cli/src/commands/generate.js

@@ -11,6 +11,15 @@ export default {
       type: 'boolean',
       default: true,
       description: 'Only generate pages for dynamic routes. Nuxt has to be built once before using this option'
+    },
+    modern: {
+      ...common.modern,
+      description: 'Generate app in modern build (modern mode can be only client)',
+      prepare(cmd, options, argv) {
+        if (argv.modern) {
+          options.modern = 'client'
+        }
+      }
     }
   },
   async run(cmd) {

packages/cli/src/commands/start.js

@@ -9,18 +9,7 @@ export default {
   usage: 'start <dir>',
   options: {
     ...common,
-    ...server,
-    modern: {
-      alias: 'm',
-      type: 'boolean',
-      description: 'Build app for modern browsers',
-      prepare(cmd, options, argv) {
-        options.build = options.build || {}
-        if (argv.modern) {
-          options.build.modern = !!argv.modern
-        }
-      }
-    }
+    ...server
   },
   async run(cmd) {
     const argv = cmd.getArgv()

packages/cli/src/options/common.js

@@ -15,6 +15,16 @@ export default {
     default: 'nuxt.config.js',
     description: 'Path to Nuxt.js config file (default: nuxt.config.js)'
   },
+  modern: {
+    alias: 'm',
+    type: 'string',
+    description: 'Build/Start app for modern browsers, e.g. server, client and false',
+    prepare(cmd, options, argv) {
+      if (argv.modern) {
+        options.modern = argv.modern
+      }
+    }
+  },
   version: {
     type: 'boolean',
     description: 'Display the Nuxt version'

packages/cli/test/unit/__snapshots__/command.test.js.snap

@@ -10,6 +10,7 @@ exports[`cli/command builds help text 1`] = `
     --spa, -s          Launch in SPA mode
     --universal, -u    Launch in Universal mode (default)
     --config-file, -c  Path to Nuxt.js config file (default: nuxt.config.js)
+    --modern, -m       Build/Start app for modern browsers, e.g. server, client and false
     --version          Display the Nuxt version
     --help, -h         Display this message
     --port, -p         Port number on which to start the application
@@ -30,6 +31,7 @@ exports[`cli/command loads command from name 1`] = `
     --spa, -s          Launch in SPA mode
     --universal, -u    Launch in Universal mode (default)
     --config-file, -c  Path to Nuxt.js config file (default: nuxt.config.js)
+    --modern, -m       Build/Start app for modern browsers, e.g. server, client and false
     --version          Display the Nuxt version
     --help, -h         Display this message
     --port, -p         Port number on which to start the application

packages/cli/test/unit/command.test.js

@@ -18,7 +18,7 @@ describe('cli/command', () => {
     const cmd = new Command({ options: allOptions })
     const minimistOptions = cmd._getMinimistOptions()
 
-    expect(minimistOptions.string.length).toBe(4)
+    expect(minimistOptions.string.length).toBe(5)
     expect(minimistOptions.boolean.length).toBe(4)
     expect(minimistOptions.alias.c).toBe('config-file')
     expect(minimistOptions.default.c).toBe(common['config-file'].default)

packages/common/src/index.js

@@ -1,2 +1,3 @@
 export { default as Hookable } from './hookable'
+export { default as ModernBrowsers } from '../data/modern-browsers.json'
 export * from './utils'

packages/config/src/config/_common.js

@@ -12,6 +12,7 @@ export default () => ({
 
   // Mode
   mode: 'universal',
+  modern: false,
 
   // Globals
   globalName: `nuxt`,

packages/config/src/config/build.js

@@ -7,7 +7,6 @@ export default () => ({
   extractCSS: false,
   cssSourceMap: undefined,
   ssr: undefined,
-  modern: undefined,
   parallel: false,
   cache: false,
   publicPath: '/_nuxt/',

packages/config/src/options.js

@@ -216,6 +216,10 @@ export function getNuxtConfig(_options) {
   const modePreset = options.modes[options.mode || 'universal']
   defaultsDeep(options, modePreset)
 
+  if (options.modern === true) {
+    options.modern = 'server'
+  }
+
   // If no server-side rendering, add appear true transition
   /* istanbul ignore if */
   if (options.render.ssr === false && options.transition) {

packages/server/package.json

@@ -11,6 +11,7 @@
     "@nuxt/common": "^2.2.0",
     "@nuxt/config": "^2.2.0",
     "@nuxtjs/youch": "^4.2.3",
+    "browserslist-useragent": "^2.0.1",
     "chalk": "^2.4.1",
     "compression": "^1.7.3",
     "connect": "^3.6.6",

packages/server/src/middleware/modern.js

@@ -0,0 +1,22 @@
+import { ModernBrowsers } from '@nuxt/common'
+import { matchesUA } from 'browserslist-useragent'
+
+const modernBrowsers = Object.keys(ModernBrowsers)
+  .map(browser => `${browser} >= ${ModernBrowsers[browser]}`)
+
+const isModernBrowser = (ua) => {
+  return Boolean(ua) && matchesUA(ua, {
+    allowHigherVersions: true,
+    browsers: modernBrowsers
+  })
+}
+
+export default function (req, res, next) {
+  const { socket = {}, headers } = req
+  if (socket.isModernBrowser === undefined) {
+    const ua = headers && headers['user-agent']
+    socket.isModernBrowser = isModernBrowser(ua)
+  }
+  req.isModernBrowser = socket.isModernBrowser
+  next()
+}

packages/server/src/server.js

@@ -13,6 +13,7 @@ import ServerContext from './context'
 import renderAndGetWindow from './jsdom'
 import nuxtMiddleware from './middleware/nuxt'
 import errorMiddleware from './middleware/error'
+import modernMiddleware from './middleware/modern'
 
 export default class Server {
   constructor(nuxt) {
@@ -29,8 +30,8 @@ export default class Server {
     this.resources = {}
 
     // Will be available on dev
-    this.webpackDevMiddleware = null
-    this.webpackHotMiddleware = null
+    this.devMiddleware = null
+    this.hotMiddleware = null
 
     // Create new connect instance
     this.app = connect()
@@ -70,14 +71,19 @@ export default class Server {
       }
     }
 
+    if (this.options.modern === 'server') {
+      this.useMiddleware(modernMiddleware)
+    }
+
     // Add webpack middleware support only for development
     if (this.options.dev) {
       this.useMiddleware(async (req, res, next) => {
-        if (this.webpackDevMiddleware) {
-          await this.webpackDevMiddleware(req, res)
+        const name = req.isModernBrowser ? 'modern' : 'client'
+        if (this.devMiddleware[name]) {
+          await this.devMiddleware[name](req, res)
         }
-        if (this.webpackHotMiddleware) {
-          await this.webpackHotMiddleware(req, res)
+        if (this.hotMiddleware[name]) {
+          await this.hotMiddleware[name](req, res)
         }
         next()
       })

packages/vue-renderer/package.json

@@ -10,7 +10,6 @@
   "dependencies": {
     "@nuxt/common": "^2.2.0",
     "@nuxtjs/devalue": "^1.1.0",
-    "browserslist-useragent": "^2.0.1",
     "consola": "^2.2.2",
     "fs-extra": "^7.0.1",
     "lru-cache": "^4.1.3",

packages/vue-renderer/src/renderer.js

@@ -3,12 +3,11 @@ import crypto from 'crypto'
 import fs from 'fs-extra'
 import consola from 'consola'
 import devalue from '@nuxtjs/devalue'
+import invert from 'lodash/invert'
 import template from 'lodash/template'
 import { waitFor } from '@nuxt/common'
-import { matchesUA } from 'browserslist-useragent'
 import { createBundleRenderer } from 'vue-server-renderer'
 
-import ModernBrowsers from '../data/modern-browsers.json'
 import SPAMetaRenderer from './spa-meta'
 
 export default class VueRenderer {
@@ -22,9 +21,6 @@ export default class VueRenderer {
       spa: null
     }
 
-    this.modernBrowsers = Object.keys(ModernBrowsers)
-      .map(browser => `${browser} >= ${ModernBrowsers[browser]}`)
-
     // Renderer runtime resources
     Object.assign(this.context.resources, {
       clientManifest: null,
@@ -36,6 +32,52 @@ export default class VueRenderer {
     })
   }
 
+  get assetsMapping() {
+    if (this._assetsMapping) return this._assetsMapping
+
+    const legacyAssets = this.context.resources.clientManifest.assetsMapping
+    const modernAssets = invert(this.context.resources.modernManifest.assetsMapping)
+    const mapping = {}
+    for (const legacyJsFile in legacyAssets) {
+      const chunkNamesHash = legacyAssets[legacyJsFile]
+      mapping[legacyJsFile] = modernAssets[chunkNamesHash]
+    }
+    delete this.context.resources.clientManifest.assetsMapping
+    delete this.context.resources.modernManifest.assetsMapping
+    this._assetsMapping = mapping
+    return mapping
+  }
+
+  renderScripts(context) {
+    if (this.context.options.modern === 'client') {
+      const publicPath = this.context.options.build.publicPath
+      const scriptPattern = /<script[^>]*?src="([^"]*)"[^>]*>[^<]*<\/script>/g
+      return context.renderScripts().replace(scriptPattern, (scriptTag, jsFile) => {
+        const legacyJsFile = jsFile.replace(publicPath, '')
+        const modernJsFile = this.assetsMapping[legacyJsFile]
+        const moduleTag = scriptTag.replace('<script', '<script type="module"').replace(legacyJsFile, modernJsFile)
+        const noModuleTag = scriptTag.replace('<script', '<script nomodule')
+        return noModuleTag + moduleTag
+      })
+    }
+    return context.renderScripts()
+  }
+
+  renderResourceHints(context) {
+    if (this.context.options.modern === 'client') {
+      const modulePreloadTags = []
+      for (const legacyJsFile of context.getPreloadFiles()) {
+        if (legacyJsFile.asType === 'script') {
+          const publicPath = this.context.options.build.publicPath
+          const modernJsFile = this.assetsMapping[legacyJsFile.file]
+          modulePreloadTags.push(`<link rel="modulepreload" href="${publicPath}${modernJsFile}" as="script">`)
+        }
+      }
+      return modulePreloadTags.join('')
+    }
+    return context.renderResourceHints()
+  }
+
   async ready() {
     // Production: Load SSR resources from fs
     if (!this.context.options.dev) {
@@ -151,7 +193,7 @@ export default class VueRenderer {
       rendererOptions
     )
 
-    if (this.context.options.build.modern) {
+    if (this.context.options.modern === 'server') {
       this.renderer.modern = createBundleRenderer(
         this.context.resources.serverBundle,
         {
@@ -186,7 +228,8 @@ export default class VueRenderer {
     context.url = url
 
     // Basic response if SSR is disabled or spa data provided
-    const spa = context.spa || (context.res && context.res.spa)
+    const { req, res } = context
+    const spa = context.spa || (res && res.spa)
     const ENV = this.context.options.env
 
     if (this.noSSR || spa) {
@@ -224,18 +267,9 @@ export default class VueRenderer {
       return { html, getPreloadFiles }
     }
 
-    const { req: { socket = {}, headers } = {} } = context
-    if (socket.isModernBrowser === undefined) {
-      const ua = headers && headers['user-agent']
-      socket.isModernBrowser = this.renderer.modern && ua && matchesUA(ua, {
-        allowHigherVersions: true,
-        browsers: this.modernBrowsers
-      })
-    }
-
     let APP
     // Call renderToString from the bundleRenderer and generate the HTML (will update the context as well)
-    if (socket.isModernBrowser) {
+    if (req && req.isModernBrowser) {
       APP = await this.renderer.modern.renderToString(context)
     } else {
       APP = await this.renderer.ssr.renderToString(context)
@@ -257,7 +291,7 @@ export default class VueRenderer {
     }
 
     if (this.context.options.render.resourceHints) {
-      HEAD += context.renderResourceHints()
+      HEAD += this.renderResourceHints(context)
     }
 
     await this.context.nuxt.callHook('render:routeContext', context.nuxt)
@@ -273,7 +307,7 @@ export default class VueRenderer {
     }
 
     APP += `<script>${serializedSession}</script>`
-    APP += context.renderScripts()
+    APP += this.renderScripts(context)
     APP += m.script.text({ body: true })
     APP += m.noscript.text({ body: true })
 

packages/webpack/src/builder.js

@@ -24,8 +24,8 @@ export class WebpackBuilder {
     // Fields that set on build
     this.compilers = []
     this.compilersWatching = []
-    this.webpackDevMiddleware = null
-    this.webpackHotMiddleware = null
+    this.devMiddleware = {}
+    this.hotMiddleware = {}
     this.perfLoader = null
 
     // Initialize shared FS and Cache
@@ -47,7 +47,7 @@ export class WebpackBuilder {
 
     // Modern
     let modernConfig
-    if (options.build.modern) {
+    if (options.modern) {
       modernConfig = new ModernConfig(this).config()
       compilersOptions.push(modernConfig)
     }
@@ -141,7 +141,7 @@ export class WebpackBuilder {
       if (options.dev) {
         // --- Dev Build ---
         // Client Build, watch is started by dev-middleware
-        if (compiler.options.name === 'client') {
+        if (['client', 'modern'].includes(name)) {
           return this.webpackDev(compiler)
         }
         // Server, build and watch for changes
@@ -178,10 +178,11 @@ export class WebpackBuilder {
   webpackDev(compiler) {
     consola.debug('Adding webpack middleware...')
 
+    const name = [compiler.options.name]
     const { nuxt: { server }, options } = this.context
 
     // Create webpack dev middleware
-    this.webpackDevMiddleware = pify(
+    this.devMiddleware[name] = pify(
       webpackDevMiddleware(
         compiler,
         Object.assign(
@@ -196,9 +197,9 @@ export class WebpackBuilder {
       )
     )
 
-    this.webpackDevMiddleware.close = pify(this.webpackDevMiddleware.close)
+    this.devMiddleware[name].close = pify(this.devMiddleware[name].close)
 
-    this.webpackHotMiddleware = pify(
+    this.hotMiddleware[name] = pify(
       webpackHotMiddleware(
         compiler,
         Object.assign(
@@ -206,15 +207,18 @@ export class WebpackBuilder {
             log: false,
             heartbeat: 10000
           },
-          options.build.hotMiddleware
+          options.build.hotMiddleware,
+          {
+            path: `/__webpack_hmr/${name}`
+          }
         )
       )
     )
 
     // Inject to renderer instance
     if (server) {
-      server.webpackDevMiddleware = this.webpackDevMiddleware
-      server.webpackHotMiddleware = this.webpackHotMiddleware
+      server.devMiddleware = this.devMiddleware
+      server.hotMiddleware = this.hotMiddleware
     }
   }
 
@@ -223,8 +227,8 @@ export class WebpackBuilder {
       watching.close()
     }
     // Stop webpack middleware
-    if (this.webpackDevMiddleware) {
-      await this.webpackDevMiddleware.close()
+    for (const devMiddleware of Object.values(this.devMiddleware)) {
+      await devMiddleware.close()
     }
   }
 

packages/webpack/src/config/client.js

@@ -103,7 +103,7 @@ export default class WebpackClientConfig extends WebpackBaseConfig {
       }, this.options.build.analyze)))
     }
 
-    if (this.options.build.modern) {
+    if (this.options.modern) {
       plugins.push(new ModernModePlugin({
         targetDir: path.resolve(this.options.buildDir, 'dist', 'client'),
         isModernBuild: this.isModern
@@ -167,9 +167,9 @@ export default class WebpackClientConfig extends WebpackBaseConfig {
     if (this.options.dev) {
       config.entry.app.unshift(
         // https://github.com/glenjamin/webpack-hot-middleware#config
-        `webpack-hot-middleware/client?name=client&reload=true&timeout=30000&path=${
+        `webpack-hot-middleware/client?name=${this.name}&reload=true&timeout=30000&path=${
           this.options.router.base
-        }/__webpack_hmr`.replace(/\/\//g, '/')
+        }/__webpack_hmr/${this.name}`.replace(/\/\//g, '/')
       )
     }
 

packages/webpack/src/config/plugins/vue/client.js

@@ -26,12 +26,20 @@ export default class VueSSRClientPlugin {
         .filter(file => isJS(file) || isCSS(file))
         .filter(file => !initialFiles.includes(file))
 
+      const assetsMapping = {}
+      stats.assets
+        .filter(({ name }) => isJS(name))
+        .forEach(({ name, chunkNames }) => {
+          assetsMapping[name] = hash(chunkNames.join('|'))
+        })
+
       const manifest = {
         publicPath: stats.publicPath,
         all: allFiles,
         initial: initialFiles,
         async: asyncFiles,
-        modules: { /* [identifier: string]: Array<index: number> */ }
+        modules: { /* [identifier: string]: Array<index: number> */ },
+        assetsMapping
       }
 
       const assetModules = stats.modules.filter(m => m.assets.length)

packages/webpack/src/config/plugins/vue/modern.js

@@ -2,12 +2,14 @@
 ** This plugin is inspired by @vue/cli-service ModernModePlugin
 ** https://github.com/vuejs/vue-cli/blob/dev/packages/@vue/cli-service/lib/webpack/ModernModePlugin.js
 */
-import path from 'path'
-import fs from 'fs-extra'
+import EventEmitter from 'events'
 
 // https://gist.github.com/samthor/64b114e4a4f539915a95b91ffd340acc
 const safariFix = `!function(){var e=document,t=e.createElement("script");if(!("noModule"in t)&&"onbeforeload"in t){var n=!1;e.addEventListener("beforeload",function(e){if(e.target===t)n=!0;else if(!e.target.hasAttribute("nomodule")||!n)return;e.preventDefault()},!0),t.type="module",t.src=".",e.head.appendChild(t),t.remove()}}();`
 
+const assetsMap = {}
+const watcher = new EventEmitter()
+
 class ModernModePlugin {
   constructor({ targetDir, isModernBuild }) {
     this.targetDir = targetDir
@@ -22,20 +24,33 @@ class ModernModePlugin {
     }
   }
 
+  set assets({ name, content }) {
+    assetsMap[name] = content
+    watcher.emit(name)
+  }
+
+  getAssets(name) {
+    return assetsMap[name] ||
+      new Promise((resolve) => {
+        watcher.once(name, () => {
+          return assetsMap[name] && resolve(assetsMap[name])
+        })
+        return assetsMap[name] && resolve(assetsMap[name])
+      })
+  }
+
   applyLegacy(compiler) {
     const ID = `nuxt-legacy-bundle`
     compiler.hooks.compilation.tap(ID, (compilation) => {
       // For html-webpack-plugin 4.0
       // HtmlWebpackPlugin.getHooks(compilation).alterAssetTags.tapAsync(ID, async (data, cb) => {
-      compilation.hooks.htmlWebpackPluginAlterAssetTags.tapAsync(ID, async (data, cb) => {
+      compilation.hooks.htmlWebpackPluginAlterAssetTags.tapAsync(ID, (data, cb) => {
         // get stats, write to disk
-        await fs.ensureDir(this.targetDir)
-        const htmlName = path.basename(data.plugin.options.filename)
-        // Watch out for output files in sub directories
-        const htmlPath = path.dirname(data.plugin.options.filename)
-        const tempFilename = path.join(this.targetDir, htmlPath, `legacy-assets-${htmlName}.json`)
-        await fs.mkdirp(path.dirname(tempFilename))
-        await fs.writeFile(tempFilename, JSON.stringify(data.body))
+        this.assets = {
+          name: data.plugin.options.filename,
+          content: data.body
+        }
+
         cb()
       })
     })
@@ -72,15 +87,16 @@ class ModernModePlugin {
         })
 
         // inject links for legacy assets as <script nomodule>
-        const htmlName = path.basename(data.plugin.options.filename)
-        // Watch out for output files in sub directories
-        const htmlPath = path.dirname(data.plugin.options.filename)
-        const tempFilename = path.join(this.targetDir, htmlPath, `legacy-assets-${htmlName}.json`)
-        const legacyAssets = JSON.parse(await fs.readFile(tempFilename, 'utf-8'))
+        const fileName = data.plugin.options.filename
+        const legacyAssets = (await this.getAssets(fileName))
           .filter(a => a.tagName === 'script' && a.attributes)
-        legacyAssets.forEach(a => (a.attributes.nomodule = ''))
-        data.body.push(...legacyAssets)
-        await fs.remove(tempFilename)
+
+        for (const a of legacyAssets) {
+          a.attributes.nomodule = ''
+          data.body.push(a)
+        }
+
+        delete assetsMap[fileName]
         cb()
       })
 

test/fixtures/modern/nuxt.config.js

@@ -1,6 +1,6 @@
 export default {
+  modern: true,
   build: {
-    modern: true,
     filenames: {
       app: ({ isModern }) => {
         return `${isModern ? 'modern-' : ''}[name].js`

test/unit/modern.client.test.js

@@ -0,0 +1,36 @@
+import { loadFixture, getPort, Nuxt, rp } from '../utils'
+
+let nuxt, port
+const url = route => 'http://localhost:' + port + route
+
+describe('modern client mode', () => {
+  beforeAll(async () => {
+    const options = await loadFixture('modern', { modern: 'client' })
+    nuxt = new Nuxt(options)
+    port = await getPort()
+    await nuxt.server.listen(port, 'localhost')
+  })
+
+  test('should contain nomodule legacy resources', async () => {
+    const response = await rp(url('/'))
+    expect(response).toContain('script nomodule src="/_nuxt/app.js')
+    expect(response).toContain('script nomodule src="/_nuxt/commons.app.js')
+  })
+
+  test('should contain module modern resources', async () => {
+    const response = await rp(url('/'))
+    expect(response).toContain('<script type="module" src="/_nuxt/modern-app.js"')
+    expect(response).toContain('<script type="module" src="/_nuxt/modern-commons.app.js"')
+  })
+
+  test('should contain module preload resources', async () => {
+    const response = await rp(url('/'))
+    expect(response).toContain('<link rel="modulepreload" href="/_nuxt/modern-app.js" as="script">')
+    expect(response).toContain('<link rel="modulepreload" href="/_nuxt/modern-commons.app.js" as="script">')
+  })
+
+  // Close server and ask nuxt to stop listening to file changes
+  afterAll(async () => {
+    await nuxt.close()
+  })
+})

test/unit/modern.server.test.js

@@ -3,9 +3,9 @@ import { loadFixture, getPort, Nuxt, rp } from '../utils'
 let nuxt, port
 const url = route => 'http://localhost:' + port + route
 
-describe('modern build', () => {
+describe('modern server mode', () => {
   beforeAll(async () => {
-    const options = await loadFixture('modern')
+    const options = await loadFixture('modern', { modern: 'server' })
     nuxt = new Nuxt(options)
     port = await getPort()
     await nuxt.server.listen(port, 'localhost')
@@ -36,4 +36,9 @@ describe('modern build', () => {
     const response = await rp(url('/_nuxt/app.js'))
     expect(response).not.toContain('arrow:()=>"build test"')
   })
+
+  // Close server and ask nuxt to stop listening to file changes
+  afterAll(async () => {
+    await nuxt.close()
+  })
 })