feat: doc tags (same as blog tags) (#3646)

* [v2] tags to doc, same as tags to blog - [IN PROGRESS]

- Addition of plugin-content-docs

- Addition of DocTagsListPage in `docusaurus-theme-classic`

! Error exists for this commit towards the theme aspect and help required.

Commit towards #3434

* docs: make tags list page work

* temp: disable onBrokenLinks

* theme bootstrap: create DocTagsListPage

* DocTagsPage added and functionality too

- individual doc tag page added to show docs for that specific tag

* Added all Docs Tags Link

* add some shared tag utils

* move tag tests to _dogfooding

* fix type

* fix some tests

* fix blog test

* refactor blog post tags handling

* better yaml tag examples

* better dogfood md files

* refactor and factorize theme tag components

* finish DocTagDocListPage

* Extract DocItemFooter + add inline tag list

* minor fix

* better typings

* fix versions.test.ts tests

* add tests for doc tags

* fix tests

* test toTagDocListProp

* move shared theme code to tagUtils

* Add new theme translation keys

* move common theme code to tagUtils + add tests

* update-code-translations should handle theme-common

* update french translation

* revert add translation

* fix pluralization problem in theme.docs.tagDocListPageTitle

* add theme component configuration options

* add more tags tests

* add documentation for docs tagging

Co-authored-by: slorber <lorber.sebastien@gmail.com>

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

@@ -22,7 +22,7 @@ import {
   STATIC_DIR_NAME,
   DEFAULT_PLUGIN_ID,
 } from '@docusaurus/core/lib/constants';
-import {flatten, take, kebabCase} from 'lodash';
+import {flatten, take} from 'lodash';
 
 import {
   PluginOptions,
@@ -51,6 +51,7 @@ import {
   generateBlogPosts,
   getContentPathList,
   getSourceToPermalink,
+  getBlogTags,
 } from './blogUtils';
 
 export default function pluginContentBlog(
@@ -65,7 +66,7 @@ export default function pluginContentBlog(
 
   const {
     siteDir,
-    siteConfig: {onBrokenMarkdownLinks},
+    siteConfig: {onBrokenMarkdownLinks, baseUrl},
     generatedFilesDir,
     i18n: {currentLocale},
   } = context;
@@ -151,17 +152,14 @@ export default function pluginContentBlog(
       const postsPerPage =
         postsPerPageOption === 'ALL' ? totalCount : postsPerPageOption;
       const numberOfPages = Math.ceil(totalCount / postsPerPage);
-      const {
-        siteConfig: {baseUrl = ''},
-      } = context;
-      const basePageUrl = normalizeUrl([baseUrl, routeBasePath]);
+      const baseBlogUrl = normalizeUrl([baseUrl, routeBasePath]);
 
       const blogListPaginated: BlogPaginated[] = [];
 
       function blogPaginationPermalink(page: number) {
         return page > 0
-          ? normalizeUrl([basePageUrl, `page/${page + 1}`])
-          : basePageUrl;
+          ? normalizeUrl([baseBlogUrl, `page/${page + 1}`])
+          : baseBlogUrl;
       }
 
       for (let page = 0; page < numberOfPages; page += 1) {
@@ -186,41 +184,9 @@ export default function pluginContentBlog(
         });
       }
 
-      const blogTags: BlogTags = {};
-      const tagsPath = normalizeUrl([basePageUrl, 'tags']);
-      blogPosts.forEach((blogPost) => {
-        const {tags} = blogPost.metadata;
-        if (!tags || tags.length === 0) {
-          // TODO: Extract tags out into a separate plugin.
-          // eslint-disable-next-line no-param-reassign
-          blogPost.metadata.tags = [];
-          return;
-        }
+      const blogTags: BlogTags = getBlogTags(blogPosts);
 
-        // eslint-disable-next-line no-param-reassign
-        blogPost.metadata.tags = tags.map((tag) => {
-          if (typeof tag === 'string') {
-            const normalizedTag = kebabCase(tag);
-            const permalink = normalizeUrl([tagsPath, normalizedTag]);
-            if (!blogTags[normalizedTag]) {
-              blogTags[normalizedTag] = {
-                // Will only use the name of the first occurrence of the tag.
-                name: tag.toLowerCase(),
-                items: [],
-                permalink,
-              };
-            }
-
-            blogTags[normalizedTag].items.push(blogPost.id);
-
-            return {
-              label: tag,
-              permalink,
-            };
-          }
-          return tag;
-        });
-      });
+      const tagsPath = normalizeUrl([baseBlogUrl, 'tags']);
 
       const blogTagsListPath =
         Object.keys(blogTags).length > 0 ? tagsPath : null;
@@ -348,6 +314,7 @@ export default function pluginContentBlog(
         Object.keys(blogTags).map(async (tag) => {
           const {name, items, permalink} = blogTags[tag];
 
+          // Refactor all this, see docs implementation
           tagsModule[tag] = {
             allTagsPath: blogTagsListPath,
             slug: tag,
@@ -535,7 +502,6 @@ export default function pluginContentBlog(
       const feedTypes = options.feedOptions.type;
       const {
         siteConfig: {title},
-        baseUrl,
       } = context;
       const feedsConfig = {
         rss: {