Only add static files route if folder exists (#9305)

* Only add static files route if folder exists

* Remove extra import

packages/next/next-server/server/next-server.ts

@@ -243,6 +243,21 @@ export default class Server {
     const publicRoutes = fs.existsSync(this.publicDir)
       ? this.generatePublicRoutes()
       : []
+    const staticFilesRoute = fs.existsSync(join(this.dir, 'static'))
+      ? [
+          {
+            // It's very important to keep this route's param optional.
+            // (but it should support as many params as needed, separated by '/')
+            // Otherwise this will lead to a pretty simple DOS attack.
+            // See more: https://github.com/zeit/next.js/issues/2617
+            match: route('/static/:path*'),
+            fn: async (req, res, params, parsedUrl) => {
+              const p = join(this.dir, 'static', ...(params.path || []))
+              await this.serveStatic(req, res, p, parsedUrl)
+            },
+          } as Route,
+        ]
+      : []
 
     const routes: Route[] = [
       {
@@ -310,17 +325,7 @@ export default class Server {
         },
       },
       ...publicRoutes,
-      {
-        // It's very important to keep this route's param optional.
-        // (but it should support as many params as needed, separated by '/')
-        // Otherwise this will lead to a pretty simple DOS attack.
-        // See more: https://github.com/zeit/next.js/issues/2617
-        match: route('/static/:path*'),
-        fn: async (req, res, params, parsedUrl) => {
-          const p = join(this.dir, 'static', ...(params.path || []))
-          await this.serveStatic(req, res, p, parsedUrl)
-        },
-      },
+      ...staticFilesRoute,
       {
         match: route('/api/:path*'),
         fn: async (req, res, params, parsedUrl) => {

test/integration/static-page-name/pages/index.js

+import Link from 'next/link'
+
+export default () => (
+  <>
+    <h3>Hello</h3>
+    <Link href='/static'>
+      <a id='to-static'>To static</a>
+    </Link>
+  </>
+)

test/integration/static-page-name/pages/static.js

+export default () => <p id='static'>hello from static page</p>

test/integration/static-page-name/test/index.test.js

+/* eslint-env jest */
+/* global jasmine */
+import path from 'path'
+import fs from 'fs-extra'
+import webdriver from 'next-webdriver'
+import {
+  launchApp,
+  killApp,
+  findPort,
+  nextBuild,
+  nextStart,
+  renderViaHTTP
+} from 'next-test-utils'
+
+jasmine.DEFAULT_TIMEOUT_INTERVAL = 1000 * 60 * 2
+
+const appDir = path.join(__dirname, '..')
+const nextConfigPath = path.join(appDir, 'next.config.js')
+let app
+let appPort
+
+const runTests = () => {
+  it('should render the page via SSR correctly', async () => {
+    const html = await renderViaHTTP(appPort, '/static')
+    expect(html).toMatch(/hello from static page/)
+  })
+
+  it('should navigate to static page name correctly', async () => {
+    const browser = await webdriver(appPort, '/')
+    await browser.elementByCss('#to-static').click()
+    await browser.waitForElementByCss('#static')
+    const html = await browser.eval(`document.documentElement.innerHTML`)
+    expect(html).toMatch(/hello from static page/)
+  })
+}
+
+describe('Static Page Name', () => {
+  describe('dev mode', () => {
+    beforeAll(async () => {
+      appPort = await findPort()
+      app = await launchApp(appDir, appPort)
+    })
+    afterAll(() => killApp(app))
+    runTests()
+  })
+
+  describe('production mode', () => {
+    beforeAll(async () => {
+      appPort = await findPort()
+      await nextBuild(appDir)
+      app = await nextStart(appDir, appPort)
+    })
+    afterAll(() => killApp(app))
+    runTests()
+  })
+
+  describe('serverless mode', () => {
+    beforeAll(async () => {
+      appPort = await findPort()
+      await fs.writeFile(
+        nextConfigPath,
+        'module.exports = { target: "serverless" }'
+      )
+      await nextBuild(appDir)
+      app = await nextStart(appDir, appPort)
+    })
+    afterAll(async () => {
+      await killApp(app)
+      await fs.remove(nextConfigPath)
+    })
+    runTests()
+  })
+})