Emit Static Export Intent (#9737)

* Emit Static Export Intent

* Remove the old export detail on rebuild

* Add test cases

* fix export

* Add a resolve return

packages/next/build/index.ts

@@ -18,6 +18,8 @@ import { verifyTypeScriptSetup } from '../lib/verifyTypeScriptSetup'
 import {
   BUILD_MANIFEST,
   DEFAULT_REDIRECT_STATUS,
+  EXPORT_DETAIL,
+  EXPORT_MARKER,
   PAGES_MANIFEST,
   PHASE_PRODUCTION_BUILD,
   PRERENDER_MANIFEST,
@@ -716,6 +718,22 @@ export default async function build(dir: string, conf = null): Promise<void> {
     )
   }
 
+  await fsWriteFile(
+    path.join(distDir, EXPORT_MARKER),
+    JSON.stringify({
+      version: 1,
+      hasExportPathMap: typeof config.exportPathMap === 'function',
+      exportTrailingSlash: config.exportTrailingSlash === true,
+    }),
+    'utf8'
+  )
+  await fsUnlink(path.join(distDir, EXPORT_DETAIL)).catch(err => {
+    if (err.code === 'ENOENT') {
+      return Promise.resolve()
+    }
+    return Promise.reject(err)
+  })
+
   staticPages.forEach(pg => allStaticPages.add(pg))
   pageInfos.forEach((info: PageInfo, key: string) => {
     allPageInfos.set(key, info)

packages/next/export/index.ts

@@ -1,11 +1,16 @@
 import chalk from 'chalk'
-import { copyFile as copyFileOrig, existsSync, readFileSync } from 'fs'
+import findUp from 'find-up'
+import {
+  copyFile as copyFileOrig,
+  existsSync,
+  readFileSync,
+  writeFileSync,
+} from 'fs'
 import Worker from 'jest-worker'
 import mkdirpModule from 'mkdirp'
 import { cpus } from 'os'
 import { dirname, join, resolve, sep } from 'path'
 import { promisify } from 'util'
-import findUp from 'find-up'
 import { AmpPageStatus, formatAmpMessages } from '../build/output/index'
 import createSpinner from '../build/spinner'
 import { API_ROUTE } from '../lib/constants'
@@ -16,11 +21,12 @@ import {
   CLIENT_PUBLIC_FILES_PATH,
   CLIENT_STATIC_FILES_PATH,
   CONFIG_FILE,
+  EXPORT_DETAIL,
   PAGES_MANIFEST,
   PHASE_EXPORT,
   PRERENDER_MANIFEST,
-  SERVER_DIRECTORY,
   SERVERLESS_DIRECTORY,
+  SERVER_DIRECTORY,
 } from '../next-server/lib/constants'
 import loadConfig, {
   isTargetLikeServerless,
@@ -180,6 +186,16 @@ export default async function(
   await recursiveDelete(join(outDir))
   await mkdirp(join(outDir, '_next', buildId))
 
+  writeFileSync(
+    join(distDir, EXPORT_DETAIL),
+    JSON.stringify({
+      version: 1,
+      outDirectory: outDir,
+      success: false,
+    }),
+    'utf8'
+  )
+
   // Copy static directory
   if (!options.buildExport && existsSync(join(dir, 'static'))) {
     log('  copying "static" directory')
@@ -372,6 +388,16 @@ export default async function(
   // Add an empty line to the console for the better readability.
   log('')
 
+  writeFileSync(
+    join(distDir, EXPORT_DETAIL),
+    JSON.stringify({
+      version: 1,
+      outDirectory: outDir,
+      success: true,
+    }),
+    'utf8'
+  )
+
   if (telemetry) {
     await telemetry.flush()
   }

packages/next/next-server/lib/constants.ts

@@ -4,6 +4,8 @@ export const PHASE_PRODUCTION_SERVER = 'phase-production-server'
 export const PHASE_DEVELOPMENT_SERVER = 'phase-development-server'
 export const PAGES_MANIFEST = 'pages-manifest.json'
 export const BUILD_MANIFEST = 'build-manifest.json'
+export const EXPORT_MARKER = 'export-marker.json'
+export const EXPORT_DETAIL = 'export-detail.json'
 export const PRERENDER_MANIFEST = 'prerender-manifest.json'
 export const ROUTES_MANIFEST = 'routes-manifest.json'
 export const REACT_LOADABLE_MANIFEST = 'react-loadable-manifest.json'

test/integration/export-intent/fixtures/bad-export/.gitignore

@@ -0,0 +1 @@
+/out

test/integration/export-intent/fixtures/bad-export/pages/index.js

@@ -0,0 +1,5 @@
+const A = () => {
+  throw new Error('fail da export')
+}
+A.getInitialProps = () => {}
+export default A

test/integration/export-intent/fixtures/custom-export/.gitignore

@@ -0,0 +1 @@
+/out

test/integration/export-intent/fixtures/custom-export/next.config.js

@@ -0,0 +1,5 @@
+module.exports = {
+  exportPathMap() {
+    return { '/': { page: '/' } }
+  },
+}

test/integration/export-intent/fixtures/custom-export/pages/index.js

@@ -0,0 +1 @@
+export default () => <div>Hello Export</div>

test/integration/export-intent/fixtures/custom-out/.gitignore

@@ -0,0 +1 @@
+/lel

test/integration/export-intent/fixtures/custom-out/next.config.js

@@ -0,0 +1,3 @@
+module.exports = {
+  exportTrailingSlash: true,
+}

test/integration/export-intent/fixtures/custom-out/pages/index.js

@@ -0,0 +1 @@
+export default () => <div>Hello Export</div>

test/integration/export-intent/fixtures/default-export/.gitignore

@@ -0,0 +1 @@
+/out

test/integration/export-intent/fixtures/default-export/pages/index.js

@@ -0,0 +1 @@
+export default () => <div>Hello Export</div>

test/integration/export-intent/fixtures/no-export/.gitignore

@@ -0,0 +1 @@
+/out

test/integration/export-intent/fixtures/no-export/pages/index.js

@@ -0,0 +1 @@
+export default () => <div>Hello Export</div>

test/integration/export-intent/test/index.test.js

@@ -0,0 +1,217 @@
+/* eslint-env jest */
+/* global jasmine */
+import { remove } from 'fs-extra'
+import { nextBuild, nextExport, nextExportDefault } from 'next-test-utils'
+import path, { join } from 'path'
+import fs from 'fs'
+
+jasmine.DEFAULT_TIMEOUT_INTERVAL = 1000 * 60 * 2
+
+const fixturesDir = join(__dirname, '..', 'fixtures')
+
+describe('Application Export Intent Output', () => {
+  describe('Default Export', () => {
+    const appDir = join(fixturesDir, 'default-export')
+    const distDir = join(appDir, '.next')
+
+    beforeAll(async () => {
+      await remove(distDir)
+    })
+
+    it('should build and export', async () => {
+      await nextBuild(appDir)
+      await nextExportDefault(appDir)
+    })
+
+    it('should have the expected outputs for export', () => {
+      expect(
+        JSON.parse(fs.readFileSync(join(distDir, 'export-marker.json'), 'utf8'))
+      ).toMatchInlineSnapshot(`
+        Object {
+          "exportTrailingSlash": false,
+          "hasExportPathMap": false,
+          "version": 1,
+        }
+      `)
+
+      const detail = JSON.parse(
+        fs.readFileSync(join(distDir, 'export-detail.json'), 'utf8')
+      )
+      expect({
+        ...detail,
+        outDirectory: path.basename(detail.outDirectory),
+      }).toMatchInlineSnapshot(`
+        Object {
+          "outDirectory": "out",
+          "success": true,
+          "version": 1,
+        }
+      `)
+    })
+  })
+
+  describe('Custom Export', () => {
+    const appDir = join(fixturesDir, 'custom-export')
+    const distDir = join(appDir, '.next')
+
+    beforeAll(async () => {
+      await remove(distDir)
+    })
+
+    it('should build and export', async () => {
+      await nextBuild(appDir)
+      await nextExportDefault(appDir)
+    })
+
+    it('should have the expected outputs for export', () => {
+      expect(
+        JSON.parse(fs.readFileSync(join(distDir, 'export-marker.json'), 'utf8'))
+      ).toMatchInlineSnapshot(`
+        Object {
+          "exportTrailingSlash": false,
+          "hasExportPathMap": true,
+          "version": 1,
+        }
+      `)
+
+      const detail = JSON.parse(
+        fs.readFileSync(join(distDir, 'export-detail.json'), 'utf8')
+      )
+      expect({
+        ...detail,
+        outDirectory: path.basename(detail.outDirectory),
+      }).toMatchInlineSnapshot(`
+        Object {
+          "outDirectory": "out",
+          "success": true,
+          "version": 1,
+        }
+      `)
+    })
+  })
+
+  describe('Custom Out', () => {
+    const appDir = join(fixturesDir, 'custom-out')
+    const distDir = join(appDir, '.next')
+
+    beforeAll(async () => {
+      await remove(distDir)
+    })
+
+    it('should build and export', async () => {
+      await nextBuild(appDir)
+      await nextExport(appDir, { outdir: join(appDir, 'lel') })
+    })
+
+    it('should have the expected outputs for export', () => {
+      expect(
+        JSON.parse(fs.readFileSync(join(distDir, 'export-marker.json'), 'utf8'))
+      ).toMatchInlineSnapshot(`
+        Object {
+          "exportTrailingSlash": true,
+          "hasExportPathMap": false,
+          "version": 1,
+        }
+      `)
+
+      const detail = JSON.parse(
+        fs.readFileSync(join(distDir, 'export-detail.json'), 'utf8')
+      )
+      expect({
+        ...detail,
+        outDirectory: path.basename(detail.outDirectory),
+      }).toMatchInlineSnapshot(`
+        Object {
+          "outDirectory": "lel",
+          "success": true,
+          "version": 1,
+        }
+      `)
+    })
+  })
+
+  describe('Bad Export', () => {
+    const appDir = join(fixturesDir, 'bad-export')
+    const distDir = join(appDir, '.next')
+
+    beforeAll(async () => {
+      await remove(distDir)
+    })
+
+    it('should build and export', async () => {
+      await nextBuild(appDir)
+      await nextExportDefault(appDir)
+    })
+
+    it('should have the expected outputs for export', () => {
+      expect(
+        JSON.parse(fs.readFileSync(join(distDir, 'export-marker.json'), 'utf8'))
+      ).toMatchInlineSnapshot(`
+        Object {
+          "exportTrailingSlash": false,
+          "hasExportPathMap": false,
+          "version": 1,
+        }
+      `)
+
+      const detail = JSON.parse(
+        fs.readFileSync(join(distDir, 'export-detail.json'), 'utf8')
+      )
+      expect({
+        ...detail,
+        outDirectory: path.basename(detail.outDirectory),
+      }).toMatchInlineSnapshot(`
+        Object {
+          "outDirectory": "out",
+          "success": false,
+          "version": 1,
+        }
+      `)
+    })
+  })
+
+  describe('No Export', () => {
+    const appDir = join(fixturesDir, 'no-export')
+    const distDir = join(appDir, '.next')
+
+    beforeAll(async () => {
+      await remove(distDir)
+    })
+
+    it('should build and not export', async () => {
+      await nextBuild(appDir)
+    })
+
+    it('should have the expected outputs for export', () => {
+      expect(
+        JSON.parse(fs.readFileSync(join(distDir, 'export-marker.json'), 'utf8'))
+      ).toMatchInlineSnapshot(`
+        Object {
+          "exportTrailingSlash": false,
+          "hasExportPathMap": false,
+          "version": 1,
+        }
+      `)
+
+      expect(() => {
+        fs.readFileSync(join(distDir, 'export-detail.json'), 'utf8')
+      }).toThrowError(/ENOENT/)
+    })
+
+    it('should export and create file', async () => {
+      await nextExportDefault(appDir)
+
+      expect(() => {
+        fs.readFileSync(join(distDir, 'export-detail.json'), 'utf8')
+      }).not.toThrow()
+    })
+
+    it('should build and clean up', async () => {
+      await nextBuild(appDir)
+
+      expect(() => {
+        fs.readFileSync(join(distDir, 'export-detail.json'), 'utf8')
+      }).toThrowError(/ENOENT/)
+    })
+  })
+})

test/lib/next-test-utils.js

@@ -192,6 +192,10 @@ export function nextExport(dir, { outdir }, opts = {}) {
   return runNextCommand(['export', dir, '--outdir', outdir], opts)
 }
 
+export function nextExportDefault(dir, opts = {}) {
+  return runNextCommand(['export', dir], opts)
+}
+
 export function nextStart(dir, port, opts = {}) {
   return runNextCommandDev(['start', '-p', port, dir], undefined, opts)
 }