Improved next/asset support (#3664)

* Allow next/asset to work properly with dynamic assetPrefix
Now we use webpack's publicPath via client side.

* Add test cases for dynamic assetPrefix and next/asset.

client/index.js

@@ -30,7 +30,10 @@ const {
   location
 } = window
 
-// With this, static assets will work across zones
+// With dynamic assetPrefix it's no longer possible to set assetPrefix at the build time
+// So, this is how we do it in the client side at runtime
+__webpack_public_path__ = `${assetPrefix}/_next/webpack/` //eslint-disable-line
+// Initialize next/asset with the assetPrefix
 asset.setAssetPrefix(assetPrefix)
 
 const asPath = getURL()

lib/asset.js

@@ -1,6 +1,11 @@
 let assetPrefix
 
 export default function asset (path) {
+  // If the URL starts with http, we assume it's an
+  if (/^https?:\/\//.test(path)) {
+    return path
+  }
+
   const pathWithoutSlash = path.replace(/^\//, '')
   return `${assetPrefix}/static/${pathWithoutSlash}`
 }

server/build/webpack.js

@@ -126,7 +126,6 @@ export default async function getBaseWebpackConfig (dir, {dev = false, isServer
       path: path.join(dir, config.distDir, isServer ? 'dist' : ''), // server compilation goes to `.next/dist`
       filename: '[name]',
       libraryTarget: 'commonjs2',
-      publicPath: `${config.assetPrefix}/_next/webpack/`,
       // This saves chunks with the name given via require.ensure()
       chunkFilename: '[name]-[chunkhash].js',
       strictModuleExceptionHandling: true,

test/integration/basic/pages/using-asset/asset.js

@@ -0,0 +1,10 @@
+import asset from 'next/asset'
+
+export default () => (
+  <div id='asset-page'>
+    <img id='img1' src={asset('/the-image')} />
+    <img id='img2' src={asset('the-image')} />
+    <img id='img3' src={asset('http://the-image.com/the-image')} />
+    <img id='img4' src={asset('https://the-image.com/the-image')} />
+  </div>
+)

test/integration/basic/pages/using-asset/index.js

@@ -0,0 +1,9 @@
+import Link from 'next/link'
+
+export default () => (
+  <div>
+    <Link href='/using-asset/asset'>
+      <a id='go-asset'>Asset</a>
+    </Link>
+  </div>
+)

test/integration/basic/test/asset.js

@@ -0,0 +1,57 @@
+/* global describe, it, expect */
+import cheerio from 'cheerio'
+import {
+  renderViaHTTP
+} from 'next-test-utils'
+import webdriver from 'next-webdriver'
+
+export default (context) => {
+  async function get$ (path) {
+    const html = await renderViaHTTP(context.appPort, path)
+    return cheerio.load(html)
+  }
+
+  describe('With next/asset', () => {
+    describe('with SSR', () => {
+      it('should handle beginning slash properly', async () => {
+        const $ = await get$('/using-asset/asset')
+        expect($('#img1').attr('src')).toBe('/static/the-image')
+        expect($('#img2').attr('src')).toBe('/static/the-image')
+      })
+
+      it('should handle http(s) properly', async () => {
+        const $ = await get$('/using-asset/asset')
+        expect($('#img3').attr('src')).toBe('http://the-image.com/the-image')
+        expect($('#img4').attr('src')).toBe('https://the-image.com/the-image')
+      })
+    })
+
+    describe('with client navigation', () => {
+      it('should handle beginning slash properly', async () => {
+        const browser = await webdriver(context.appPort, '/using-asset')
+        await browser
+          .elementByCss('#go-asset').click()
+          .waitForElementByCss('#asset-page')
+
+        expect(await browser.elementByCss('#img1').getAttribute('src'))
+          .toBe(`http://localhost:${context.appPort}/static/the-image`)
+        expect(await browser.elementByCss('#img2').getAttribute('src'))
+          .toBe(`http://localhost:${context.appPort}/static/the-image`)
+        browser.close()
+      })
+
+      it('should handle http(s) properly', async () => {
+        const browser = await webdriver(context.appPort, '/using-asset')
+        await browser
+          .elementByCss('#go-asset').click()
+          .waitForElementByCss('#asset-page')
+
+        expect(await browser.elementByCss('#img3').getAttribute('src'))
+          .toBe('http://the-image.com/the-image')
+        expect(await browser.elementByCss('#img4').getAttribute('src'))
+          .toBe('https://the-image.com/the-image')
+        browser.close()
+      })
+    })
+  })
+}

test/integration/basic/test/index.test.js

@@ -14,6 +14,7 @@ import rendering from './rendering'
 import clientNavigation from './client-navigation'
 import hmr from './hmr'
 import dynamic from './dynamic'
+import asset from './asset'
 
 const context = {}
 jasmine.DEFAULT_TIMEOUT_INTERVAL = 1000 * 60 * 5
@@ -60,4 +61,5 @@ describe('Basic Features', () => {
   clientNavigation(context, (p, q) => renderViaHTTP(context.appPort, p, q))
   dynamic(context, (p, q) => renderViaHTTP(context.appPort, p, q))
   hmr(context, (p, q) => renderViaHTTP(context.appPort, p, q))
+  asset(context)
 })

test/integration/custom-server/pages/asset.js

@@ -0,0 +1,7 @@
+import asset from 'next/asset'
+
+export default () => (
+  <div id='asset-page'>
+    <img src={asset('/myimage.png')} />
+  </div>
+)

test/integration/custom-server/pages/index.js

@@ -1,3 +1,9 @@
+import Link from 'next/link'
+
 export default () => (
-  <div>My Homepage</div>
+  <div>
+    <Link href='/asset'>
+      <a id='go-asset'>Asset</a>
+    </Link>
+  </div>
 )

test/integration/custom-server/server.js

@@ -11,7 +11,7 @@ const handleNextRequests = app.getRequestHandler()
 app.prepare().then(() => {
   const server = micro((req, res) => {
     if (/setAssetPrefix/.test(req.url)) {
-      app.setAssetPrefix('https://cdn.com/myapp')
+      app.setAssetPrefix(`http://127.0.0.1:${port}`)
     } else {
       // This is to support multi-zones support in localhost
       // and may be in staging deployments

test/integration/custom-server/test/index.test.js

@@ -3,11 +3,13 @@
 import { join } from 'path'
 import getPort from 'get-port'
 import clone from 'clone'
+import cheerio from 'cheerio'
 import {
   initNextServerScript,
   killApp,
   renderViaHTTP
 } from 'next-test-utils'
+import webdriver from 'next-webdriver'
 
 const appDir = join(__dirname, '../')
 let appPort
@@ -29,23 +31,51 @@ describe('Custom Server', () => {
 
   describe('with dynamic assetPrefix', () => {
     it('should set the assetPrefix dynamically', async () => {
-      const normalUsage = await renderViaHTTP(appPort, '/')
-      expect(normalUsage).not.toMatch(/cdn\.com\/myapp/)
+      const normalUsage = await renderViaHTTP(appPort, '/asset')
+      expect(normalUsage).not.toMatch(/127\.0\.0\.1/)
 
-      const dynamicUsage = await renderViaHTTP(appPort, '/?setAssetPrefix=1')
-      expect(dynamicUsage).toMatch(/cdn\.com\/myapp/)
+      const dynamicUsage = await renderViaHTTP(appPort, '/asset?setAssetPrefix=1')
+      expect(dynamicUsage).toMatch(/127\.0\.0\.1/)
     })
 
     it('should set the assetPrefix to a given request', async () => {
       for (let lc = 0; lc < 1000; lc++) {
         const [normalUsage, dynamicUsage] = await Promise.all([
-          await renderViaHTTP(appPort, '/'),
-          await renderViaHTTP(appPort, '/?setAssetPrefix=1')
+          await renderViaHTTP(appPort, '/asset'),
+          await renderViaHTTP(appPort, '/asset?setAssetPrefix=1')
         ])
 
-        expect(normalUsage).not.toMatch(/cdn\.com\/myapp/)
-        expect(dynamicUsage).toMatch(/cdn\.com\/myapp/)
+        expect(normalUsage).not.toMatch(/127\.0\.0\.1/)
+        expect(dynamicUsage).toMatch(/127\.0\.0\.1/)
       }
     })
+
+    it('should support next/asset in server side', async () => {
+      const $normal = cheerio.load(await renderViaHTTP(appPort, '/asset'))
+      expect($normal('img').attr('src')).toBe('/static/myimage.png')
+
+      const $dynamic = cheerio.load(await renderViaHTTP(appPort, '/asset?setAssetPrefix=1'))
+      expect($dynamic('img').attr('src')).toBe(`http://127.0.0.1:${context.appPort}/static/myimage.png`)
+    })
+
+    it('should support next/asset in client side', async() => {
+      const browser = await webdriver(context.appPort, '/')
+      await browser
+        .elementByCss('#go-asset').click()
+        .waitForElementByCss('#asset-page')
+
+      expect(await browser.elementByCss('img').getAttribute('src'))
+        .toBe(`http://localhost:${context.appPort}/static/myimage.png`)
+      browser.close()
+
+      const browser2 = await webdriver(context.appPort, '/?setAssetPrefix=1')
+      await browser2
+        .elementByCss('#go-asset').click()
+        .waitForElementByCss('#asset-page')
+
+      expect(await browser2.elementByCss('img').getAttribute('src'))
+        .toBe(`http://127.0.0.1:${context.appPort}/static/myimage.png`)
+      browser2.close()
+    })
   })
 })