docs(v2): analytics (#1678)

* docs(v2): analytics

* docs(v2): rework analytics docs

* fix broken link

website/docs/advanced-plugins.md

@@ -166,18 +166,55 @@ module.exports = {
 
 ### `@docusaurus/plugin-google-analytics`
 
-The classic template ships with this plugin for Google Analytics. To use this analytics, specify the plugin in the `plugins` field, and provide your Google Analytics configuration in [theme config](./using-themes.md).
+The default [Google Analytics](https://developers.google.com/analytics/devguides/collection/analyticsjs/) plugin.
+
+**Installation**
+
+```shell
+$ yarn add @docusaurus/plugin-google-analytics
+```
+
+**Configuration**
 
 ```js
 // docusaurus.config.js
 module.exports = {
-  plugins: ['@docusaurus/plugin-google-analytics'],
+  plugins: [
+    [
+      '@docusaurus/plugin-google-analytics',
+      {
+        trackingID: 'UA-142857148-5',
+      },
+    ],
+  ],
 };
 ```
 
 ### `@docusaurus/plugin-google-gtag`
 
-_This section is a work in progress. [Welcoming PRs](https://github.com/facebook/docusaurus/issues/1640)._
+The default [Global Site Tag (gtag.js)](https://developers.google.com/analytics/devguides/collection/gtagjs/) plugin.
+
+**Installation**
+
+```shell
+$ yarn add @docusaurus/plugin-google-gtag
+```
+
+**Configuration**
+
+```js
+// docusaurus.config.js
+module.exports = {
+  plugins: [
+    [
+      '@docusaurus/plugin-google-gtag',
+      {
+        trackingID: 'UA-142857148-5',
+      },
+    ],
+  ],
+};
+```
 
 ### `@docusaurus/plugin-sitemap`
 

website/docs/analytics.md

@@ -0,0 +1,47 @@
+---
+id: analytics
+title: Analytics
+keywords:
+  - docusaurus
+  - analytics
+---
+
+This page describes how to configure a Docusaurus site to enable Google's libraries and SDKs for tracking.
+
+## `@docusaurus/plugin-google-analytics`
+
+[Google's analytics.js library](https://developers.google.com/analytics/devguides/collection/analyticsjs/) is a JavaScript library for measuring how users interact with your website. This section explains how to configure a Docusaurus site to enable Google Analytics.
+
+If you generalized your site using Docusaurus' classic template, ou may enable the analytics plugin directly by specifying the Google Analytics tracking id via the `themeConfig` field:
+
+```js
+// docusaurus.config.js
+module.exports = {
+  themeConfig: {
+    googleAnalytics: {
+      trackingID: 'UA-142857148-5',
+    },
+  },
+};
+```
+
+To learn how to manually set up the Google Analytics plugin for Docusaurus sites not generated from the classic template, refer to [Advanced Guides: Plugins – `@docusaurus/plugin-google-analytics`](advanced-plugins.md#docusaurusplugin-google-analytics).
+
+## `@docusaurus/plugin-google-gtag`
+
+Google's [Global Site Tag (gtag.js)](https://developers.google.com/analytics/devguides/collection/gtagjs/) is a JavaScript tagging framework and API that allows you to send event data to Google Analytics, Google Ads, and Google Marketing Platform. This section describes how to configure a Docusaurus site to enable global site tag for Google Analytics.
+
+If you generalized your site using Docusaurus' classic template, ou may enable the gtag plugin directly by specifying the gtag tracking id via the `themeConfig` field:
+
+```js
+// docusaurus.config.js
+module.exports = {
+  themeConfig: {
+    gtag: {
+      trackingID: 'UA-142857148-5',
+    },
+  },
+};
+```
+
+To learn how to manually set up the gtag plugin for Docusaurus sites not generated from the classic template, refer to [Advanced Guides: Plugins – `@docusaurus/plugin-google-gtag`](advanced-plugins.md#docusaurusplugin-google-gtag).

website/docs/reaching-users.md

@@ -1,35 +0,0 @@
----
-id: reaching-users
-title: Reaching Users
-keywords:
-  - docusaurus
-  - seo
-  - analytics
----
-
-## Search
-
-_This section is a work in progress. [Welcoming PRs](https://github.com/facebook/docusaurus/issues/1640)._
-
-<!--
-
-References
----
-- [Docusaurus v1 search](https://docusaurus.io/docs/en/search)
-- [Algolia documentation](https://www.algolia.com/doc/)
--->
-
-## Analytics
-
-_This section is a work in progress. [Welcoming PRs](https://github.com/facebook/docusaurus/issues/1640)._
-
-<!--
-
-Cover actual usage guidelines of adding analytics to sites.
-
-References
----
-- [source code](packages/docusaurus-plugin-google-analytics/src/index.js)
-- [plugins](plugins.md)
-
--->

website/docs/search.md

@@ -0,0 +1,19 @@
+---
+id: search
+title: Search
+keywords:
+  - docusaurus
+  - search
+---
+
+## Search
+
+_This section is a work in progress. [Welcoming PRs](https://github.com/facebook/docusaurus/issues/1640)._
+
+<!--
+
+References
+---
+- [Docusaurus v1 search](https://docusaurus.io/docs/en/search)
+- [Algolia documentation](https://www.algolia.com/doc/)
+-->

website/sidebars.js

@@ -23,8 +23,9 @@ module.exports = {
         items: ['markdown-features', 'sidebar'],
       },
       'blog',
+      'analytics',
       'seo',
-      // 'reaching-users', // add back analytics and search
+      'search',
       'using-plugins',
       'using-themes',
       'deployment',