perf: avoid duplicated git log calls in loadContent() and postBuild() for untracked Git files (#11211)

Co-authored-by: slorber <749374+slorber@users.noreply.github.com>

packages/docusaurus-plugin-content-blog/src/plugin-content-blog.d.ts

@@ -521,9 +521,9 @@ declare module '@docusaurus/plugin-content-blog' {
       readingTime: ReadingTimeFunctionOption;
       /** Governs the direction of blog post sorting. */
       sortPosts: 'ascending' | 'descending';
-      /**	Whether to display the last date the doc was updated. */
+      /**	Whether to display the last date the blog post was updated. */
       showLastUpdateTime: boolean;
-      /** Whether to display the author who last updated the doc. */
+      /** Whether to display the author who last updated the blog post. */
       showLastUpdateAuthor: boolean;
       /** An optional function which can be used to transform blog posts
        *  (filter, modify, delete, etc...).

packages/docusaurus-plugin-sitemap/src/__tests__/createSitemapItem.test.ts

@@ -225,5 +225,66 @@ describe('createSitemapItem', () => {
         `);
       });
     });
+
+    describe('read from both - route metadata lastUpdatedAt null', () => {
+      const route = {
+        path: '/routePath',
+        metadata: {
+          sourceFilePath: 'route/file.md',
+          lastUpdatedAt: null,
+        },
+      };
+
+      it('lastmod default option', async () => {
+        await expect(
+          test({
+            route,
+          }),
+        ).resolves.toMatchInlineSnapshot(`
+              {
+                "changefreq": "weekly",
+                "lastmod": null,
+                "priority": 0.5,
+                "url": "https://example.com/routePath",
+              }
+          `);
+      });
+
+      it('lastmod date option', async () => {
+        await expect(
+          test({
+            route,
+            options: {
+              lastmod: 'date',
+            },
+          }),
+        ).resolves.toMatchInlineSnapshot(`
+          {
+            "changefreq": "weekly",
+            "lastmod": null,
+            "priority": 0.5,
+            "url": "https://example.com/routePath",
+          }
+        `);
+      });
+
+      it('lastmod datetime option', async () => {
+        await expect(
+          test({
+            route,
+            options: {
+              lastmod: 'datetime',
+            },
+          }),
+        ).resolves.toMatchInlineSnapshot(`
+          {
+            "changefreq": "weekly",
+            "lastmod": null,
+            "priority": 0.5,
+            "url": "https://example.com/routePath",
+          }
+        `);
+      });
+    });
   });
 });

packages/docusaurus-plugin-sitemap/src/createSitemapItem.ts

@@ -13,13 +13,19 @@ import type {PluginOptions} from './options';
 
 async function getRouteLastUpdatedAt(
   route: RouteConfig,
-): Promise<number | undefined> {
+): Promise<number | null | undefined> {
+  // Important to bail-out early here
+  // This can lead to duplicated getLastUpdate() calls and performance problems
+  // See https://github.com/facebook/docusaurus/pull/11211
+  if (route.metadata?.lastUpdatedAt === null) {
+    return null;
+  }
   if (route.metadata?.lastUpdatedAt) {
     return route.metadata?.lastUpdatedAt;
   }
   if (route.metadata?.sourceFilePath) {
     const lastUpdate = await getLastUpdate(route.metadata?.sourceFilePath);
-    return lastUpdate?.lastUpdatedAt;
+    return lastUpdate?.lastUpdatedAt ?? null;
   }
 
   return undefined;

packages/docusaurus-theme-classic/src/theme-classic.d.ts

@@ -852,8 +852,8 @@ declare module '@theme/EditMetaRow' {
   export interface Props {
     readonly className: string;
     readonly editUrl: string | null | undefined;
-    readonly lastUpdatedAt: number | undefined;
-    readonly lastUpdatedBy: string | undefined;
+    readonly lastUpdatedAt: number | null | undefined;
+    readonly lastUpdatedBy: string | null | undefined;
   }
   export default function EditMetaRow(props: Props): ReactNode;
 }
@@ -1024,8 +1024,8 @@ declare module '@theme/LastUpdated' {
   import type {ReactNode} from 'react';
 
   export interface Props {
-    readonly lastUpdatedAt?: number;
-    readonly lastUpdatedBy?: string;
+    readonly lastUpdatedAt?: number | null;
+    readonly lastUpdatedBy?: string | null;
   }
 
   export default function LastUpdated(props: Props): ReactNode;

packages/docusaurus-types/src/routing.d.ts

@@ -56,12 +56,19 @@ export type RouteMetadata = {
   /**
    * The last updated date of this route
    * This is generally read from the Git history of the sourceFilePath
-   * but can also be provided through other means (usually front matter)
+   * but can also be provided through other means (usually front matter).
    *
    * This has notably been introduced for adding "lastmod" support to the
    * sitemap plugin, see https://github.com/facebook/docusaurus/pull/9954
+   *
+   * `undefined` means we haven't tried to compute the value for this route.
+   * This is usually the case for routes created by third-party plugins that do
+   * not need this metadata.
+   *
+   * `null` means we already tried to compute a lastUpdatedAt, but we know for
+   * sure there isn't any. This usually happens for untracked Git files.
    */
-  lastUpdatedAt?: number;
+  lastUpdatedAt?: number | null;
 };
 
 /**

packages/docusaurus-utils/src/__tests__/lastUpdateUtils.test.ts

@@ -14,8 +14,10 @@ import execa from 'execa';
 import {
   getGitLastUpdate,
   LAST_UPDATE_FALLBACK,
+  LAST_UPDATE_UNTRACKED_GIT_FILEPATH,
   readLastUpdateData,
 } from '../lastUpdateUtils';
+import type {FrontMatterLastUpdate} from '../lastUpdateUtils';
 
 describe('getGitLastUpdate', () => {
   const {repoDir} = createTempRepo();
@@ -109,6 +111,34 @@ describe('readLastUpdateData', () => {
   const testTimestamp = new Date(testDate).getTime();
   const testAuthor = 'ozaki';
 
+  describe('on untracked Git file', () => {
+    function test(lastUpdateFrontMatter: FrontMatterLastUpdate | undefined) {
+      return readLastUpdateData(
+        LAST_UPDATE_UNTRACKED_GIT_FILEPATH,
+        {showLastUpdateAuthor: true, showLastUpdateTime: true},
+        lastUpdateFrontMatter,
+      );
+    }
+
+    it('reads null at/by from Git', async () => {
+      const {lastUpdatedAt, lastUpdatedBy} = await test({});
+      expect(lastUpdatedAt).toBeNull();
+      expect(lastUpdatedBy).toBeNull();
+    });
+
+    it('reads null at from Git and author from front matter', async () => {
+      const {lastUpdatedAt, lastUpdatedBy} = await test({author: testAuthor});
+      expect(lastUpdatedAt).toBeNull();
+      expect(lastUpdatedBy).toEqual(testAuthor);
+    });
+
+    it('reads null by from Git and date from front matter', async () => {
+      const {lastUpdatedAt, lastUpdatedBy} = await test({date: testDate});
+      expect(lastUpdatedBy).toBeNull();
+      expect(lastUpdatedAt).toEqual(testTimestamp);
+    });
+  });
+
   it('read last time show author time', async () => {
     const {lastUpdatedAt, lastUpdatedBy} = await readLastUpdateData(
       '',

packages/docusaurus-utils/src/gitUtils.ts

@@ -154,12 +154,12 @@ export async function getFileCommitDate(
     file,
   )}"`;
 
-  const result = (await GitCommandQueue.add(() =>
-    execa(command, {
+  const result = (await GitCommandQueue.add(() => {
+    return execa(command, {
       cwd: path.dirname(file),
       shell: true,
-    }),
-  ))!;
+    });
+  }))!;
 
   if (result.exitCode !== 0) {
     throw new Error(

packages/docusaurus-utils/src/lastUpdateUtils.ts

@@ -15,10 +15,18 @@ import {
 import type {PluginOptions} from '@docusaurus/types';
 
 export type LastUpdateData = {
-  /** A timestamp in **milliseconds**, usually read from `git log` */
-  lastUpdatedAt?: number;
-  /** The author's name, usually coming from `git log` */
-  lastUpdatedBy?: string;
+  /**
+   * A timestamp in **milliseconds**, usually read from `git log`
+   * `undefined`: not read
+   * `null`: no value to read (usual for untracked files)
+   */
+  lastUpdatedAt: number | undefined | null;
+  /**
+   * The author's name, usually coming from `git log`
+   * `undefined`: not read
+   * `null`: no value to read (usual for untracked files)
+   */
+  lastUpdatedBy: string | undefined | null;
 };
 
 let showedGitRequirementError = false;
@@ -68,9 +76,15 @@ export const LAST_UPDATE_FALLBACK: LastUpdateData = {
   lastUpdatedBy: 'Author',
 };
 
+// Not proud of this, but convenient for tests :/
+export const LAST_UPDATE_UNTRACKED_GIT_FILEPATH = `file/path/${Math.random()}.mdx`;
+
 export async function getLastUpdate(
   filePath: string,
 ): Promise<LastUpdateData | null> {
+  if (filePath === LAST_UPDATE_UNTRACKED_GIT_FILEPATH) {
+    return null;
+  }
   if (
     process.env.NODE_ENV !== 'production' ||
     process.env.DOCUSAURUS_DISABLE_LAST_UPDATE === 'true'
@@ -103,7 +117,7 @@ export async function readLastUpdateData(
   const {showLastUpdateAuthor, showLastUpdateTime} = options;
 
   if (!showLastUpdateAuthor && !showLastUpdateTime) {
-    return {};
+    return {lastUpdatedBy: undefined, lastUpdatedAt: undefined};
   }
 
   const frontMatterAuthor = lastUpdateFrontMatter?.author;
@@ -116,9 +130,21 @@ export async function readLastUpdateData(
   // If all the data is provided as front matter, we do not call it
   const getLastUpdateMemoized = _.memoize(() => getLastUpdate(filePath));
   const getLastUpdateBy = () =>
-    getLastUpdateMemoized().then((update) => update?.lastUpdatedBy);
+    getLastUpdateMemoized().then((update) => {
+      // Important, see https://github.com/facebook/docusaurus/pull/11211
+      if (update === null) {
+        return null;
+      }
+      return update?.lastUpdatedBy;
+    });
   const getLastUpdateAt = () =>
-    getLastUpdateMemoized().then((update) => update?.lastUpdatedAt);
+    getLastUpdateMemoized().then((update) => {
+      // Important, see https://github.com/facebook/docusaurus/pull/11211
+      if (update === null) {
+        return null;
+      }
+      return update?.lastUpdatedAt;
+    });
 
   const lastUpdatedBy = showLastUpdateAuthor
     ? frontMatterAuthor ?? (await getLastUpdateBy())

packages/docusaurus/src/commands/build/buildLocale.ts

@@ -35,6 +35,7 @@ export type BuildLocaleParams = {
 };
 
 const SkipBundling = process.env.DOCUSAURUS_SKIP_BUNDLING === 'true';
+const ExitAfterLoading = process.env.DOCUSAURUS_EXIT_AFTER_LOADING === 'true';
 const ExitAfterBundling = process.env.DOCUSAURUS_EXIT_AFTER_BUNDLING === 'true';
 
 export async function buildLocale({
@@ -59,6 +60,10 @@ export async function buildLocale({
     }),
   );
 
+  if (ExitAfterLoading) {
+    return process.exit(0);
+  }
+
   const {props} = site;
   const {outDir, plugins, siteConfig} = props;
 

website/docusaurus.config.ts

@@ -316,6 +316,10 @@ export default async function createConfigAsync() {
         './src/plugins/changelog/index.ts',
         {
           blogTitle: 'Docusaurus changelog',
+          // Not useful, but permits to run git commands earlier
+          // Otherwise the sitemap plugin will run them in postBuild()
+          showLastUpdateAuthor: true,
+          showLastUpdateTime: true,
           blogDescription:
             'Keep yourself up-to-date about new features in every release',
           blogSidebarCount: 'ALL',