Merge pull request #3656 from BookStackApp/x_linking

Link reference tracking & updating

.env.example.complete

@@ -299,7 +299,7 @@ APP_DEFAULT_DARK_MODE=false
 # Page revision limit
 # Number of page revisions to keep in the system before deleting old revisions.
 # If set to 'false' a limit will not be enforced.
-REVISION_LIMIT=50
+REVISION_LIMIT=100
 
 # Recycle Bin Lifetime
 # The number of days that content will remain in the recycle bin before

app/Config/app.php

@@ -22,7 +22,7 @@ return [
     // The number of revisions to keep in the database.
     // Once this limit is reached older revisions will be deleted.
     // If set to false then a limit will not be enforced.
-    'revision_limit' => env('REVISION_LIMIT', 50),
+    'revision_limit' => env('REVISION_LIMIT',  100),
 
     // The number of days that content will remain in the recycle bin before
     // being considered for auto-removal. It is not a guarantee that content will

app/Console/Commands/RegenerateCommentContent.php

@@ -5,6 +5,7 @@ namespace BookStack\Console\Commands;
 use BookStack\Actions\Comment;
 use BookStack\Actions\CommentRepo;
 use Illuminate\Console\Command;
+use Illuminate\Support\Facades\DB;
 
 class RegenerateCommentContent extends Command
 {
@@ -43,9 +44,9 @@ class RegenerateCommentContent extends Command
      */
     public function handle()
     {
-        $connection = \DB::getDefaultConnection();
+        $connection = DB::getDefaultConnection();
         if ($this->option('database') !== null) {
-            \DB::setDefaultConnection($this->option('database'));
+            DB::setDefaultConnection($this->option('database'));
         }
 
         Comment::query()->chunk(100, function ($comments) {
@@ -55,7 +56,8 @@ class RegenerateCommentContent extends Command
             }
         });
 
-        \DB::setDefaultConnection($connection);
+        DB::setDefaultConnection($connection);
         $this->comment('Comment HTML content has been regenerated');
+        return 0;
     }
 }

app/Console/Commands/RegeneratePermissions.php

@@ -50,5 +50,6 @@ class RegeneratePermissions extends Command
 
         DB::setDefaultConnection($connection);
         $this->comment('Permissions regenerated');
+        return 0;
     }
 }

app/Console/Commands/RegenerateReferences.php

@@ -0,0 +1,58 @@
+<?php
+
+namespace BookStack\Console\Commands;
+
+use BookStack\References\ReferenceStore;
+use Illuminate\Console\Command;
+use Illuminate\Support\Facades\DB;
+
+class RegenerateReferences extends Command
+{
+    /**
+     * The name and signature of the console command.
+     *
+     * @var string
+     */
+    protected $signature = 'bookstack:regenerate-references {--database= : The database connection to use.}';
+
+    /**
+     * The console command description.
+     *
+     * @var string
+     */
+    protected $description = 'Regenerate all the cross-item model reference index';
+
+    protected ReferenceStore $references;
+
+    /**
+     * Create a new command instance.
+     *
+     * @return void
+     */
+    public function __construct(ReferenceStore $references)
+    {
+        $this->references = $references;
+        parent::__construct();
+    }
+
+    /**
+     * Execute the console command.
+     *
+     * @return int
+     */
+    public function handle()
+    {
+        $connection = DB::getDefaultConnection();
+
+        if ($this->option('database')) {
+            DB::setDefaultConnection($this->option('database'));
+        }
+
+        $this->references->updateForAllPages();
+
+        DB::setDefaultConnection($connection);
+
+        $this->comment('References have been regenerated');
+        return 0;
+    }
+}

app/Entities/Models/BookChild.php

@@ -2,6 +2,7 @@
 
 namespace BookStack\Entities\Models;
 
+use BookStack\References\ReferenceUpdater;
 use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
 
@@ -57,9 +58,15 @@ abstract class BookChild extends Entity
      */
     public function changeBook(int $newBookId): Entity
     {
+        $oldUrl = $this->getUrl();
         $this->book_id = $newBookId;
         $this->refreshSlug();
         $this->save();
+
+        if ($oldUrl !== $this->getUrl()) {
+            app()->make(ReferenceUpdater::class)->updateEntityPageReferences($this, $oldUrl);
+        }
+
         $this->refresh();
 
         // Update all child pages if a chapter

app/Entities/Models/Entity.php

@@ -18,6 +18,7 @@ use BookStack\Interfaces\Loggable;
 use BookStack\Interfaces\Sluggable;
 use BookStack\Interfaces\Viewable;
 use BookStack\Model;
+use BookStack\References\Reference;
 use BookStack\Search\SearchIndex;
 use BookStack\Search\SearchTerm;
 use BookStack\Traits\HasCreatorAndUpdater;
@@ -203,6 +204,22 @@ abstract class Entity extends Model implements Sluggable, Favouritable, Viewable
         return $this->morphMany(Deletion::class, 'deletable');
     }
 
+    /**
+     * Get the references pointing from this entity to other items.
+     */
+    public function referencesFrom(): MorphMany
+    {
+        return $this->morphMany(Reference::class, 'from');
+    }
+
+    /**
+     * Get the references pointing to this entity from other items.
+     */
+    public function referencesTo(): MorphMany
+    {
+        return $this->morphMany(Reference::class, 'to');
+    }
+
     /**
      * Check if this instance or class is a certain type of entity.
      * Examples of $type are 'page', 'book', 'chapter'.

app/Entities/Repos/BaseRepo.php

@@ -6,6 +6,7 @@ use BookStack\Actions\TagRepo;
 use BookStack\Entities\Models\Entity;
 use BookStack\Entities\Models\HasCoverImage;
 use BookStack\Exceptions\ImageUploadException;
+use BookStack\References\ReferenceUpdater;
 use BookStack\Uploads\ImageRepo;
 use Illuminate\Http\UploadedFile;
 
@@ -13,11 +14,13 @@ class BaseRepo
 {
     protected TagRepo $tagRepo;
     protected ImageRepo $imageRepo;
+    protected ReferenceUpdater $referenceUpdater;
 
-    public function __construct(TagRepo $tagRepo, ImageRepo $imageRepo)
+    public function __construct(TagRepo $tagRepo, ImageRepo $imageRepo, ReferenceUpdater $referenceUpdater)
     {
         $this->tagRepo = $tagRepo;
         $this->imageRepo = $imageRepo;
+        $this->referenceUpdater = $referenceUpdater;
     }
 
     /**
@@ -48,6 +51,8 @@ class BaseRepo
      */
     public function update(Entity $entity, array $input)
     {
+        $oldUrl = $entity->getUrl();
+
         $entity->fill($input);
         $entity->updated_by = user()->id;
 
@@ -64,6 +69,10 @@ class BaseRepo
 
         $entity->rebuildPermissions();
         $entity->indexForSearch();
+
+        if ($oldUrl !== $entity->getUrl()) {
+            $this->referenceUpdater->updateEntityPageReferences($entity, $oldUrl);
+        }
     }
 
     /**

app/Entities/Repos/PageRepo.php

@@ -16,20 +16,32 @@ use BookStack\Exceptions\MoveOperationException;
 use BookStack\Exceptions\NotFoundException;
 use BookStack\Exceptions\PermissionsException;
 use BookStack\Facades\Activity;
+use BookStack\References\ReferenceStore;
+use BookStack\References\ReferenceUpdater;
 use Exception;
-use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Pagination\LengthAwarePaginator;
 
 class PageRepo
 {
-    protected $baseRepo;
+    protected BaseRepo $baseRepo;
+    protected RevisionRepo $revisionRepo;
+    protected ReferenceStore $referenceStore;
+    protected ReferenceUpdater $referenceUpdater;
 
     /**
      * PageRepo constructor.
      */
-    public function __construct(BaseRepo $baseRepo)
+    public function __construct(
+        BaseRepo         $baseRepo,
+        RevisionRepo     $revisionRepo,
+        ReferenceStore   $referenceStore,
+        ReferenceUpdater $referenceUpdater
+    )
     {
         $this->baseRepo = $baseRepo;
+        $this->revisionRepo = $revisionRepo;
+        $this->referenceStore = $referenceStore;
+        $this->referenceUpdater = $referenceUpdater;
     }
 
     /**
@@ -39,6 +51,7 @@ class PageRepo
      */
     public function getById(int $id, array $relations = ['book']): Page
     {
+        /** @var Page $page */
         $page = Page::visible()->with($relations)->find($id);
 
         if (!$page) {
@@ -70,17 +83,7 @@ class PageRepo
      */
     public function getByOldSlug(string $bookSlug, string $pageSlug): ?Page
     {
-        /** @var ?PageRevision $revision */
-        $revision = PageRevision::query()
-            ->whereHas('page', function (Builder $query) {
-                $query->scopes('visible');
-            })
-            ->where('slug', '=', $pageSlug)
-            ->where('type', '=', 'version')
-            ->where('book_slug', '=', $bookSlug)
-            ->orderBy('created_at', 'desc')
-            ->with('page')
-            ->first();
+        $revision = $this->revisionRepo->getBySlugs($bookSlug, $pageSlug);
 
         return $revision->page ?? null;
     }
@@ -112,7 +115,7 @@ class PageRepo
     public function getParentFromSlugs(string $bookSlug, string $chapterSlug = null): Entity
     {
         if ($chapterSlug !== null) {
-            return $chapter = Chapter::visible()->whereSlugs($bookSlug, $chapterSlug)->firstOrFail();
+            return Chapter::visible()->whereSlugs($bookSlug, $chapterSlug)->firstOrFail();
         }
 
         return Book::visible()->where('slug', '=', $bookSlug)->firstOrFail();
@@ -123,9 +126,7 @@ class PageRepo
      */
     public function getUserDraft(Page $page): ?PageRevision
     {
-        $revision = $this->getUserDraftQuery($page)->first();
-
-        return $revision;
+        return $this->revisionRepo->getLatestDraftForCurrentUser($page);
     }
 
     /**
@@ -134,11 +135,11 @@ class PageRepo
     public function getNewDraftPage(Entity $parent)
     {
         $page = (new Page())->forceFill([
-            'name'       => trans('entities.pages_initial_name'),
+            'name' => trans('entities.pages_initial_name'),
             'created_by' => user()->id,
-            'owned_by'   => user()->id,
+            'owned_by' => user()->id,
             'updated_by' => user()->id,
-            'draft'      => true,
+            'draft' => true,
         ]);
 
         if ($parent instanceof Chapter) {
@@ -165,11 +166,10 @@ class PageRepo
         $draft->draft = false;
         $draft->revision_count = 1;
         $draft->priority = $this->getNewPriority($draft);
-        $draft->refreshSlug();
         $draft->save();
 
-        $this->savePageRevision($draft, trans('entities.pages_initial_revision'));
-        $draft->indexForSearch();
+        $this->revisionRepo->storeNewForPage($draft, trans('entities.pages_initial_revision'));
+        $this->referenceStore->updateForPage($draft);
         $draft->refresh();
 
         Activity::add(ActivityType::PAGE_CREATE, $draft);
@@ -189,13 +189,14 @@ class PageRepo
 
         $this->updateTemplateStatusAndContentFromInput($page, $input);
         $this->baseRepo->update($page, $input);
+        $this->referenceStore->updateForPage($page);
 
         // Update with new details
         $page->revision_count++;
         $page->save();
 
         // Remove all update drafts for this user & page.
-        $this->getUserDraftQuery($page)->delete();
+        $this->revisionRepo->deleteDraftsForCurrentUser($page);
 
         // Save a revision after updating
         $summary = trim($input['summary'] ?? '');
@@ -203,7 +204,7 @@ class PageRepo
         $nameChanged = isset($input['name']) && $input['name'] !== $oldName;
         $markdownChanged = isset($input['markdown']) && $input['markdown'] !== $oldMarkdown;
         if ($htmlChanged || $nameChanged || $markdownChanged || $summary) {
-            $this->savePageRevision($page, $summary);
+            $this->revisionRepo->storeNewForPage($page, $summary);
         }
 
         Activity::add(ActivityType::PAGE_UPDATE, $page);
@@ -239,32 +240,6 @@ class PageRepo
         }
     }
 
-    /**
-     * Saves a page revision into the system.
-     */
-    protected function savePageRevision(Page $page, string $summary = null): PageRevision
-    {
-        $revision = new PageRevision();
-
-        $revision->name = $page->name;
-        $revision->html = $page->html;
-        $revision->markdown = $page->markdown;
-        $revision->text = $page->text;
-        $revision->page_id = $page->id;
-        $revision->slug = $page->slug;
-        $revision->book_slug = $page->book->slug;
-        $revision->created_by = user()->id;
-        $revision->created_at = $page->updated_at;
-        $revision->type = 'version';
-        $revision->summary = $summary;
-        $revision->revision_number = $page->revision_count;
-        $revision->save();
-
-        $this->deleteOldRevisions($page);
-
-        return $revision;
-    }
-
     /**
      * Save a page update draft.
      */
@@ -280,7 +255,7 @@ class PageRepo
         }
 
         // Otherwise, save the data to a revision
-        $draft = $this->getPageRevisionToUpdate($page);
+        $draft = $this->revisionRepo->getNewDraftForCurrentUser($page);
         $draft->fill($input);
 
         if (!empty($input['markdown'])) {
@@ -314,6 +289,7 @@ class PageRepo
      */
     public function restoreRevision(Page $page, int $revisionId): Page
     {
+        $oldUrl = $page->getUrl();
         $page->revision_count++;
 
         /** @var PageRevision $revision */
@@ -332,9 +308,14 @@ class PageRepo
         $page->refreshSlug();
         $page->save();
         $page->indexForSearch();
+        $this->referenceStore->updateForPage($page);
 
         $summary = trans('entities.pages_revision_restored_from', ['id' => strval($revisionId), 'summary' => $revision->summary]);
-        $this->savePageRevision($page, $summary);
+        $this->revisionRepo->storeNewForPage($page, $summary);
+
+        if ($oldUrl !== $page->getUrl()) {
+            $this->referenceUpdater->updateEntityPageReferences($page, $oldUrl);
+        }
 
         Activity::add(ActivityType::PAGE_RESTORE, $page);
         Activity::add(ActivityType::REVISION_RESTORE, $revision);
@@ -393,48 +374,6 @@ class PageRepo
         return $parentClass::visible()->where('id', '=', $entityId)->first();
     }
 
-    /**
-     * Get a page revision to update for the given page.
-     * Checks for an existing revisions before providing a fresh one.
-     */
-    protected function getPageRevisionToUpdate(Page $page): PageRevision
-    {
-        $drafts = $this->getUserDraftQuery($page)->get();
-        if ($drafts->count() > 0) {
-            return $drafts->first();
-        }
-
-        $draft = new PageRevision();
-        $draft->page_id = $page->id;
-        $draft->slug = $page->slug;
-        $draft->book_slug = $page->book->slug;
-        $draft->created_by = user()->id;
-        $draft->type = 'update_draft';
-
-        return $draft;
-    }
-
-    /**
-     * Delete old revisions, for the given page, from the system.
-     */
-    protected function deleteOldRevisions(Page $page)
-    {
-        $revisionLimit = config('app.revision_limit');
-        if ($revisionLimit === false) {
-            return;
-        }
-
-        $revisionsToDelete = PageRevision::query()
-            ->where('page_id', '=', $page->id)
-            ->orderBy('created_at', 'desc')
-            ->skip(intval($revisionLimit))
-            ->take(10)
-            ->get(['id']);
-        if ($revisionsToDelete->count() > 0) {
-            PageRevision::query()->whereIn('id', $revisionsToDelete->pluck('id'))->delete();
-        }
-    }
-
     /**
      * Get a new priority for a page.
      */
@@ -450,15 +389,4 @@ class PageRepo
 
         return (new BookContents($page->book))->getLastPriority() + 1;
     }
-
-    /**
-     * Get the query to find the user's draft copies of the given page.
-     */
-    protected function getUserDraftQuery(Page $page)
-    {
-        return PageRevision::query()->where('created_by', '=', user()->id)
-            ->where('type', 'update_draft')
-            ->where('page_id', '=', $page->id)
-            ->orderBy('created_at', 'desc');
-    }
 }

app/Entities/Repos/RevisionRepo.php

@@ -0,0 +1,131 @@
+<?php
+
+namespace BookStack\Entities\Repos;
+
+use BookStack\Entities\Models\Page;
+use BookStack\Entities\Models\PageRevision;
+use Illuminate\Database\Eloquent\Builder;
+
+class RevisionRepo
+{
+    /**
+     * Get a revision by its stored book and page slug values.
+     */
+    public function getBySlugs(string $bookSlug, string $pageSlug): ?PageRevision
+    {
+        /** @var ?PageRevision $revision */
+        $revision = PageRevision::query()
+            ->whereHas('page', function (Builder $query) {
+                $query->scopes('visible');
+            })
+            ->where('slug', '=', $pageSlug)
+            ->where('type', '=', 'version')
+            ->where('book_slug', '=', $bookSlug)
+            ->orderBy('created_at', 'desc')
+            ->with('page')
+            ->first();
+
+        return $revision;
+    }
+
+    /**
+     * Get the latest draft revision, for the given page, belonging to the current user.
+     */
+    public function getLatestDraftForCurrentUser(Page $page): ?PageRevision
+    {
+        /** @var ?PageRevision $revision */
+        $revision = $this->queryForCurrentUserDraft($page->id)->first();
+
+        return $revision;
+    }
+
+    /**
+     * Delete all drafts revisions, for the given page, belonging to the current user.
+     */
+    public function deleteDraftsForCurrentUser(Page $page): void
+    {
+        $this->queryForCurrentUserDraft($page->id)->delete();
+    }
+
+    /**
+     * Get a user update_draft page revision to update for the given page.
+     * Checks for an existing revisions before providing a fresh one.
+     */
+    public function getNewDraftForCurrentUser(Page $page): PageRevision
+    {
+        $draft = $this->getLatestDraftForCurrentUser($page);
+
+        if ($draft) {
+            return $draft;
+        }
+
+        $draft = new PageRevision();
+        $draft->page_id = $page->id;
+        $draft->slug = $page->slug;
+        $draft->book_slug = $page->book->slug;
+        $draft->created_by = user()->id;
+        $draft->type = 'update_draft';
+
+        return $draft;
+    }
+
+    /**
+     * Store a new revision in the system for the given page.
+     */
+    public function storeNewForPage(Page $page, string $summary = null): PageRevision
+    {
+        $revision = new PageRevision();
+
+        $revision->name = $page->name;
+        $revision->html = $page->html;
+        $revision->markdown = $page->markdown;
+        $revision->text = $page->text;
+        $revision->page_id = $page->id;
+        $revision->slug = $page->slug;
+        $revision->book_slug = $page->book->slug;
+        $revision->created_by = user()->id;
+        $revision->created_at = $page->updated_at;
+        $revision->type = 'version';
+        $revision->summary = $summary;
+        $revision->revision_number = $page->revision_count;
+        $revision->save();
+
+        $this->deleteOldRevisions($page);
+
+        return $revision;
+    }
+
+    /**
+     * Delete old revisions, for the given page, from the system.
+     */
+    protected function deleteOldRevisions(Page $page)
+    {
+        $revisionLimit = config('app.revision_limit');
+        if ($revisionLimit === false) {
+            return;
+        }
+
+        $revisionsToDelete = PageRevision::query()
+            ->where('page_id', '=', $page->id)
+            ->orderBy('created_at', 'desc')
+            ->skip(intval($revisionLimit))
+            ->take(10)
+            ->get(['id']);
+
+        if ($revisionsToDelete->count() > 0) {
+            PageRevision::query()->whereIn('id', $revisionsToDelete->pluck('id'))->delete();
+        }
+    }
+
+    /**
+     * Query update draft revisions for the current user.
+     */
+    protected function queryForCurrentUserDraft(int $pageId): Builder
+    {
+        return PageRevision::query()
+            ->where('created_by', '=', user()->id)
+            ->where('type', 'update_draft')
+            ->where('page_id', '=', $pageId)
+            ->orderBy('created_at', 'desc');
+    }
+}

app/Entities/Tools/TrashCan.php

@@ -376,6 +376,8 @@ class TrashCan
         $entity->searchTerms()->delete();
         $entity->deletions()->delete();
         $entity->favourites()->delete();
+        $entity->referencesTo()->delete();
+        $entity->referencesFrom()->delete();
 
         if ($entity instanceof HasCoverImage && $entity->cover()->exists()) {
             $imageService = app()->make(ImageService::class);

app/Http/Controllers/BookController.php

@@ -15,19 +15,22 @@ use BookStack\Entities\Tools\ShelfContext;
 use BookStack\Exceptions\ImageUploadException;
 use BookStack\Exceptions\NotFoundException;
 use BookStack\Facades\Activity;
+use BookStack\References\ReferenceFetcher;
 use Illuminate\Http\Request;
 use Illuminate\Validation\ValidationException;
 use Throwable;
 
 class BookController extends Controller
 {
-    protected $bookRepo;
-    protected $entityContextManager;
+    protected BookRepo $bookRepo;
+    protected ShelfContext $shelfContext;
+    protected ReferenceFetcher $referenceFetcher;
 
-    public function __construct(ShelfContext $entityContextManager, BookRepo $bookRepo)
+    public function __construct(ShelfContext $entityContextManager, BookRepo $bookRepo, ReferenceFetcher $referenceFetcher)
     {
         $this->bookRepo = $bookRepo;
-        $this->entityContextManager = $entityContextManager;
+        $this->shelfContext = $entityContextManager;
+        $this->referenceFetcher = $referenceFetcher;
     }
 
     /**
@@ -44,7 +47,7 @@ class BookController extends Controller
         $popular = $this->bookRepo->getPopular(4);
         $new = $this->bookRepo->getRecentlyCreated(4);
 
-        $this->entityContextManager->clearShelfContext();
+        $this->shelfContext->clearShelfContext();
 
         $this->setPageTitle(trans('entities.books'));
 
@@ -122,7 +125,7 @@ class BookController extends Controller
 
         View::incrementFor($book);
         if ($request->has('shelf')) {
-            $this->entityContextManager->setShelfContext(intval($request->get('shelf')));
+            $this->shelfContext->setShelfContext(intval($request->get('shelf')));
         }
 
         $this->setPageTitle($book->getShortName());
@@ -133,6 +136,7 @@ class BookController extends Controller
             'bookChildren'      => $bookChildren,
             'bookParentShelves' => $bookParentShelves,
             'activity'          => $activities->entityActivity($book, 20, 1),
+            'referenceCount'    => $this->referenceFetcher->getPageReferenceCountToEntity($book),
         ]);
     }
 

app/Http/Controllers/BookshelfController.php

@@ -10,6 +10,7 @@ use BookStack\Entities\Tools\PermissionsUpdater;
 use BookStack\Entities\Tools\ShelfContext;
 use BookStack\Exceptions\ImageUploadException;
 use BookStack\Exceptions\NotFoundException;
+use BookStack\References\ReferenceFetcher;
 use Exception;
 use Illuminate\Http\Request;
 use Illuminate\Validation\ValidationException;
@@ -18,11 +19,13 @@ class BookshelfController extends Controller
 {
     protected BookshelfRepo $shelfRepo;
     protected ShelfContext $shelfContext;
+    protected ReferenceFetcher $referenceFetcher;
 
-    public function __construct(BookshelfRepo $shelfRepo, ShelfContext $shelfContext)
+    public function __construct(BookshelfRepo $shelfRepo, ShelfContext $shelfContext, ReferenceFetcher $referenceFetcher)
     {
         $this->shelfRepo = $shelfRepo;
         $this->shelfContext = $shelfContext;
+        $this->referenceFetcher = $referenceFetcher;
     }
 
     /**
@@ -124,6 +127,7 @@ class BookshelfController extends Controller
             'activity'                => $activities->entityActivity($shelf, 20, 1),
             'order'                   => $order,
             'sort'                    => $sort,
+            'referenceCount'          => $this->referenceFetcher->getPageReferenceCountToEntity($shelf),
         ]);
     }
 

app/Http/Controllers/ChapterController.php

@@ -13,20 +13,21 @@ use BookStack\Entities\Tools\PermissionsUpdater;
 use BookStack\Exceptions\MoveOperationException;
 use BookStack\Exceptions\NotFoundException;
 use BookStack\Exceptions\PermissionsException;
+use BookStack\References\ReferenceFetcher;
 use Illuminate\Http\Request;
 use Illuminate\Validation\ValidationException;
 use Throwable;
 
 class ChapterController extends Controller
 {
-    protected $chapterRepo;
+    protected ChapterRepo $chapterRepo;
+    protected ReferenceFetcher $referenceFetcher;
 
-    /**
-     * ChapterController constructor.
-     */
-    public function __construct(ChapterRepo $chapterRepo)
+
+    public function __construct(ChapterRepo $chapterRepo, ReferenceFetcher $referenceFetcher)
     {
         $this->chapterRepo = $chapterRepo;
+        $this->referenceFetcher = $referenceFetcher;
     }
 
     /**
@@ -77,13 +78,14 @@ class ChapterController extends Controller
         $this->setPageTitle($chapter->getShortName());
 
         return view('chapters.show', [
-            'book'        => $chapter->book,
-            'chapter'     => $chapter,
-            'current'     => $chapter,
-            'sidebarTree' => $sidebarTree,
-            'pages'       => $pages,
-            'next'        => $nextPreviousLocator->getNext(),
-            'previous'    => $nextPreviousLocator->getPrevious(),
+            'book'           => $chapter->book,
+            'chapter'        => $chapter,
+            'current'        => $chapter,
+            'sidebarTree'    => $sidebarTree,
+            'pages'          => $pages,
+            'next'           => $nextPreviousLocator->getNext(),
+            'previous'       => $nextPreviousLocator->getPrevious(),
+            'referenceCount' => $this->referenceFetcher->getPageReferenceCountToEntity($chapter),
         ]);
     }
 

app/Http/Controllers/MaintenanceController.php

@@ -5,6 +5,7 @@ namespace BookStack\Http\Controllers;
 use BookStack\Actions\ActivityType;
 use BookStack\Entities\Tools\TrashCan;
 use BookStack\Notifications\TestEmail;
+use BookStack\References\ReferenceStore;
 use BookStack\Uploads\ImageService;
 use Illuminate\Http\Request;
 
@@ -74,6 +75,24 @@ class MaintenanceController extends Controller
             $this->showErrorNotification($errorMessage);
         }
 
-        return redirect('/settings/maintenance#image-cleanup')->withInput();
+        return redirect('/settings/maintenance#image-cleanup');
+    }
+
+    /**
+     * Action to regenerate the reference index in the system.
+     */
+    public function regenerateReferences(ReferenceStore $referenceStore)
+    {
+        $this->checkPermission('settings-manage');
+        $this->logActivity(ActivityType::MAINTENANCE_ACTION_RUN, 'regenerate-references');
+
+        try {
+            $referenceStore->updateForAllPages();
+            $this->showSuccessNotification(trans('settings.maint_regen_references_success'));
+        } catch (\Exception $exception) {
+            $this->showErrorNotification($exception->getMessage());
+        }
+
+        return redirect('/settings/maintenance#regenerate-references');
     }
 }

app/Http/Controllers/PageController.php

@@ -14,6 +14,7 @@ use BookStack\Entities\Tools\PageEditorData;
 use BookStack\Entities\Tools\PermissionsUpdater;
 use BookStack\Exceptions\NotFoundException;
 use BookStack\Exceptions\PermissionsException;
+use BookStack\References\ReferenceFetcher;
 use Exception;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Http\Request;
@@ -23,13 +24,15 @@ use Throwable;
 class PageController extends Controller
 {
     protected PageRepo $pageRepo;
+    protected ReferenceFetcher $referenceFetcher;
 
     /**
      * PageController constructor.
      */
-    public function __construct(PageRepo $pageRepo)
+    public function __construct(PageRepo $pageRepo, ReferenceFetcher $referenceFetcher)
     {
         $this->pageRepo = $pageRepo;
+        $this->referenceFetcher = $referenceFetcher;
     }
 
     /**
@@ -160,6 +163,7 @@ class PageController extends Controller
             'pageNav'         => $pageNav,
             'next'            => $nextPreviousLocator->getNext(),
             'previous'        => $nextPreviousLocator->getPrevious(),
+            'referenceCount'  => $this->referenceFetcher->getPageReferenceCountToEntity($page),
         ]);
     }
 

app/Http/Controllers/ReferenceController.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace BookStack\Http\Controllers;
+
+use BookStack\Entities\Models\Book;
+use BookStack\Entities\Models\Bookshelf;
+use BookStack\Entities\Models\Chapter;
+use BookStack\Entities\Models\Page;
+use BookStack\References\ReferenceFetcher;
+
+class ReferenceController extends Controller
+{
+    protected ReferenceFetcher $referenceFetcher;
+
+    public function __construct(ReferenceFetcher $referenceFetcher)
+    {
+        $this->referenceFetcher = $referenceFetcher;
+    }
+
+    /**
+     * Display the references to a given page.
+     */
+    public function page(string $bookSlug, string $pageSlug)
+    {
+        /** @var Page $page */
+        $page = Page::visible()->whereSlugs($bookSlug, $pageSlug)->firstOrFail();
+        $references = $this->referenceFetcher->getPageReferencesToEntity($page);
+
+        return view('pages.references', [
+            'page' => $page,
+            'references' => $references,
+        ]);
+    }
+
+    /**
+     * Display the references to a given chapter.
+     */
+    public function chapter(string $bookSlug, string $chapterSlug)
+    {
+        /** @var Chapter $chapter */
+        $chapter = Chapter::visible()->whereSlugs($bookSlug, $chapterSlug)->firstOrFail();
+        $references = $this->referenceFetcher->getPageReferencesToEntity($chapter);
+
+        return view('chapters.references', [
+            'chapter' => $chapter,
+            'references' => $references,
+        ]);
+    }
+
+    /**
+     * Display the references to a given book.
+     */
+    public function book(string $slug)
+    {
+        $book = Book::visible()->where('slug', '=', $slug)->firstOrFail();
+        $references = $this->referenceFetcher->getPageReferencesToEntity($book);
+
+        return view('books.references', [
+            'book' => $book,
+            'references' => $references,
+        ]);
+    }
+
+    /**
+     * Display the references to a given shelf.
+     */
+    public function shelf(string $slug)
+    {
+        $shelf = Bookshelf::visible()->where('slug', '=', $slug)->firstOrFail();
+        $references = $this->referenceFetcher->getPageReferencesToEntity($shelf);
+
+        return view('shelves.references', [
+            'shelf' => $shelf,
+            'references' => $references,
+        ]);
+    }
+}

app/References/CrossLinkParser.php

@@ -0,0 +1,103 @@
+<?php
+
+namespace BookStack\References;
+
+use BookStack\Model;
+use BookStack\References\ModelResolvers\BookLinkModelResolver;
+use BookStack\References\ModelResolvers\BookshelfLinkModelResolver;
+use BookStack\References\ModelResolvers\ChapterLinkModelResolver;
+use BookStack\References\ModelResolvers\CrossLinkModelResolver;
+use BookStack\References\ModelResolvers\PageLinkModelResolver;
+use BookStack\References\ModelResolvers\PagePermalinkModelResolver;
+use DOMDocument;
+use DOMXPath;
+
+class CrossLinkParser
+{
+    /**
+     * @var CrossLinkModelResolver[]
+     */
+    protected array $modelResolvers;
+
+    public function __construct(array $modelResolvers)
+    {
+        $this->modelResolvers = $modelResolvers;
+    }
+
+    /**
+     * Extract any found models within the given HTML content.
+     *
+     * @return Model[]
+     */
+    public function extractLinkedModels(string $html): array
+    {
+        $models = [];
+
+        $links = $this->getLinksFromContent($html);
+
+        foreach ($links as $link) {
+            $model = $this->linkToModel($link);
+            if (!is_null($model)) {
+                $models[get_class($model) . ':' . $model->id] = $model;
+            }
+        }
+
+        return array_values($models);
+    }
+
+    /**
+     * Get a list of href values from the given document.
+     *
+     * @returns string[]
+     */
+    protected function getLinksFromContent(string $html): array
+    {
+        $links = [];
+
+        $html = '<body>' . $html . '</body>';
+        libxml_use_internal_errors(true);
+        $doc = new DOMDocument();
+        $doc->loadHTML(mb_convert_encoding($html, 'HTML-ENTITIES', 'UTF-8'));
+
+        $xPath = new DOMXPath($doc);
+        $anchors = $xPath->query('//a[@href]');
+
+        /** @var \DOMElement $anchor */
+        foreach ($anchors as $anchor) {
+            $links[] = $anchor->getAttribute('href');
+        }
+
+        return $links;
+    }
+
+    /**
+     * Attempt to resolve the given link to a model using the instance model resolvers.
+     */
+    protected function linkToModel(string $link): ?Model
+    {
+        foreach ($this->modelResolvers as $resolver) {
+            $model = $resolver->resolve($link);
+            if (!is_null($model)) {
+                return $model;
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Create a new instance with a pre-defined set of model resolvers, specifically for the
+     * default set of entities within BookStack.
+     */
+    public static function createWithEntityResolvers(): self
+    {
+        return new self([
+            new PagePermalinkModelResolver(),
+            new PageLinkModelResolver(),
+            new ChapterLinkModelResolver(),
+            new BookLinkModelResolver(),
+            new BookshelfLinkModelResolver(),
+        ]);
+    }
+
+}

app/References/ModelResolvers/BookLinkModelResolver.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace BookStack\References\ModelResolvers;
+
+use BookStack\Entities\Models\Book;
+use BookStack\Model;
+
+class BookLinkModelResolver implements CrossLinkModelResolver
+{
+    public function resolve(string $link): ?Model
+    {
+        $pattern = '/^' . preg_quote(url('/books'), '/') . '\/([\w-]+)' . '([#?\/]|$)/';
+        $matches = [];
+        $match = preg_match($pattern, $link, $matches);
+        if (!$match) {
+            return null;
+        }
+
+        $bookSlug = $matches[1];
+
+        /** @var ?Book $model */
+        $model = Book::query()->where('slug', '=',  $bookSlug)->first(['id']);
+
+        return $model;
+    }
+}

app/References/ModelResolvers/BookshelfLinkModelResolver.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace BookStack\References\ModelResolvers;
+
+use BookStack\Entities\Models\Bookshelf;
+use BookStack\Model;
+
+class BookshelfLinkModelResolver implements CrossLinkModelResolver
+{
+    public function resolve(string $link): ?Model
+    {
+        $pattern = '/^' . preg_quote(url('/shelves'), '/') . '\/([\w-]+)' . '([#?\/]|$)/';
+        $matches = [];
+        $match = preg_match($pattern, $link, $matches);
+        if (!$match) {
+            return null;
+        }
+
+        $shelfSlug = $matches[1];
+
+        /** @var ?Bookshelf $model */
+        $model = Bookshelf::query()->where('slug', '=',  $shelfSlug)->first(['id']);
+
+        return $model;
+    }
+}

app/References/ModelResolvers/ChapterLinkModelResolver.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace BookStack\References\ModelResolvers;
+
+use BookStack\Entities\Models\Chapter;
+use BookStack\Model;
+
+class ChapterLinkModelResolver implements CrossLinkModelResolver
+{
+    public function resolve(string $link): ?Model
+    {
+        $pattern = '/^' . preg_quote(url('/books'), '/') . '\/([\w-]+)' . '\/chapter\/' . '([\w-]+)' . '([#?\/]|$)/';
+        $matches = [];
+        $match = preg_match($pattern, $link, $matches);
+        if (!$match) {
+            return null;
+        }
+
+        $bookSlug = $matches[1];
+        $chapterSlug = $matches[2];
+
+        /** @var ?Chapter $model */
+        $model = Chapter::query()->whereSlugs($bookSlug, $chapterSlug)->first(['id']);
+
+        return $model;
+    }
+}

app/References/ModelResolvers/CrossLinkModelResolver.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace BookStack\References\ModelResolvers;
+
+use BookStack\Model;
+
+interface CrossLinkModelResolver
+{
+    /**
+     * Resolve the given href link value to a model.
+     */
+    public function resolve(string $link): ?Model;
+}

app/References/ModelResolvers/PageLinkModelResolver.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace BookStack\References\ModelResolvers;
+
+use BookStack\Entities\Models\Page;
+use BookStack\Model;
+
+class PageLinkModelResolver implements CrossLinkModelResolver
+{
+    public function resolve(string $link): ?Model
+    {
+        $pattern = '/^' . preg_quote(url('/books'), '/') . '\/([\w-]+)' . '\/page\/' . '([\w-]+)' . '([#?\/]|$)/';
+        $matches = [];
+        $match = preg_match($pattern, $link, $matches);
+        if (!$match) {
+            return null;
+        }
+
+        $bookSlug = $matches[1];
+        $pageSlug = $matches[2];
+
+        /** @var ?Page $model */
+        $model = Page::query()->whereSlugs($bookSlug, $pageSlug)->first(['id']);
+
+        return $model;
+    }
+}

app/References/ModelResolvers/PagePermalinkModelResolver.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace BookStack\References\ModelResolvers;
+
+use BookStack\Entities\Models\Page;
+use BookStack\Model;
+
+class PagePermalinkModelResolver implements CrossLinkModelResolver
+{
+    public function resolve(string $link): ?Model
+    {
+        $pattern = '/^' . preg_quote(url('/link'), '/') . '\/(\d+)/';
+        $matches = [];
+        $match = preg_match($pattern, $link, $matches);
+        if (!$match) {
+            return null;
+        }
+
+        $id = intval($matches[1]);
+        /** @var ?Page $model */
+        $model = Page::query()->find($id, ['id']);
+
+        return $model;
+    }
+}

app/References/Reference.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace BookStack\References;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\MorphTo;
+
+/**
+ * @property int $from_id
+ * @property string $from_type
+ * @property int $to_id
+ * @property string $to_type
+ */
+class Reference extends Model
+{
+    public $timestamps = false;
+
+    public function from(): MorphTo
+    {
+        return $this->morphTo('from');
+    }
+
+    public function to(): MorphTo
+    {
+        return $this->morphTo('to');
+    }
+}

app/References/ReferenceFetcher.php

@@ -0,0 +1,62 @@
+<?php
+
+namespace BookStack\References;
+
+use BookStack\Auth\Permissions\PermissionApplicator;
+use BookStack\Entities\Models\Entity;
+use BookStack\Entities\Models\Page;
+use Illuminate\Database\Eloquent\Collection;
+use Illuminate\Database\Eloquent\Relations\Relation;
+
+class ReferenceFetcher
+{
+    protected PermissionApplicator $permissions;
+
+    public function __construct(PermissionApplicator $permissions)
+    {
+        $this->permissions = $permissions;
+    }
+
+    /**
+     * Query and return the page references pointing to the given entity.
+     * Loads the commonly required relations while taking permissions into account.
+     */
+    public function getPageReferencesToEntity(Entity $entity): Collection
+    {
+        $baseQuery = $entity->referencesTo()
+            ->where('from_type', '=', (new Page())->getMorphClass())
+            ->with([
+                'from' => fn(Relation $query) => $query->select(Page::$listAttributes),
+                'from.book' => fn(Relation $query) => $query->scopes('visible'),
+                'from.chapter' => fn(Relation $query) => $query->scopes('visible')
+            ]);
+
+        $references = $this->permissions->restrictEntityRelationQuery(
+            $baseQuery,
+            'references',
+            'from_id',
+            'from_type'
+        )->get();
+
+        return $references;
+    }
+
+    /**
+     * Returns the count of page references pointing to the given entity.
+     * Takes permissions into account.
+     */
+    public function getPageReferenceCountToEntity(Entity $entity): int
+    {
+        $baseQuery = $entity->referencesTo()
+            ->where('from_type', '=', (new Page())->getMorphClass());
+
+        $count = $this->permissions->restrictEntityRelationQuery(
+            $baseQuery,
+            'references',
+            'from_id',
+            'from_type'
+        )->count();
+
+        return $count;
+    }
+}

app/References/ReferenceStore.php

@@ -0,0 +1,71 @@
+<?php
+
+namespace BookStack\References;
+
+use BookStack\Entities\Models\Page;
+use Illuminate\Database\Eloquent\Collection;
+
+class ReferenceStore
+{
+
+    /**
+     * Update the outgoing references for the given page.
+     */
+    public function updateForPage(Page $page): void
+    {
+        $this->updateForPages([$page]);
+    }
+
+    /**
+     * Update the outgoing references for all pages in the system.
+     */
+    public function updateForAllPages(): void
+    {
+        Reference::query()
+            ->where('from_type', '=', (new Page())->getMorphClass())
+            ->delete();
+
+        Page::query()->select(['id', 'html'])->chunk(100, function(Collection $pages) {
+            $this->updateForPages($pages->all());
+        });
+    }
+
+    /**
+     * Update the outgoing references for the pages in the given array.
+     *
+     * @param Page[] $pages
+     */
+    protected function updateForPages(array $pages): void
+    {
+        if (count($pages) === 0) {
+            return;
+        }
+
+        $parser = CrossLinkParser::createWithEntityResolvers();
+        $references = [];
+
+        $pageIds = array_map(fn(Page $page) => $page->id, $pages);
+        Reference::query()
+            ->where('from_type', '=', $pages[0]->getMorphClass())
+            ->whereIn('from_id', $pageIds)
+            ->delete();
+
+        foreach ($pages as $page) {
+            $models = $parser->extractLinkedModels($page->html);
+
+            foreach ($models as $model) {
+                $references[] = [
+                    'from_id' => $page->id,
+                    'from_type' => $page->getMorphClass(),
+                    'to_id' => $model->id,
+                    'to_type' => $model->getMorphClass(),
+                ];
+            }
+        }
+
+        foreach (array_chunk($references, 1000) as $referenceDataChunk) {
+            Reference::query()->insert($referenceDataChunk);
+        }
+    }
+
+}

app/References/ReferenceUpdater.php

@@ -0,0 +1,94 @@
+<?php
+
+namespace BookStack\References;
+
+use BookStack\Entities\Models\Entity;
+use BookStack\Entities\Models\Page;
+use BookStack\Entities\Repos\RevisionRepo;
+use DOMDocument;
+use DOMXPath;
+
+class ReferenceUpdater
+{
+    protected ReferenceFetcher $referenceFetcher;
+    protected RevisionRepo $revisionRepo;
+
+    public function __construct(ReferenceFetcher $referenceFetcher, RevisionRepo $revisionRepo)
+    {
+        $this->referenceFetcher = $referenceFetcher;
+        $this->revisionRepo = $revisionRepo;
+    }
+
+    public function updateEntityPageReferences(Entity $entity, string $oldLink)
+    {
+        $references = $this->referenceFetcher->getPageReferencesToEntity($entity);
+        $newLink = $entity->getUrl();
+
+        /** @var Reference $reference */
+        foreach ($references as $reference) {
+            /** @var Page $page */
+            $page = $reference->from;
+            $this->updateReferencesWithinPage($page, $oldLink, $newLink);
+        }
+    }
+
+    protected function updateReferencesWithinPage(Page $page, string $oldLink, string $newLink)
+    {
+        $page = (clone $page)->refresh();
+        $html = $this->updateLinksInHtml($page->html, $oldLink, $newLink);
+        $markdown = $this->updateLinksInMarkdown($page->markdown, $oldLink, $newLink);
+
+        $page->html = $html;
+        $page->markdown = $markdown;
+        $page->revision_count++;
+        $page->save();
+
+        $summary = trans('entities.pages_references_update_revision');
+        $this->revisionRepo->storeNewForPage($page, $summary);
+    }
+
+    protected function updateLinksInMarkdown(string $markdown, string $oldLink, string $newLink): string
+    {
+        if (empty($markdown)) {
+            return $markdown;
+        }
+
+        $commonLinkRegex = '/(\[.*?\]\()' . preg_quote($oldLink, '/') . '(.*?\))/i';
+        $markdown = preg_replace($commonLinkRegex, '$1' . $newLink . '$2', $markdown);
+
+        $referenceLinkRegex = '/(\[.*?\]:\s?)' . preg_quote($oldLink, '/') . '(.*?)($|\s)/i';
+        $markdown = preg_replace($referenceLinkRegex, '$1' . $newLink . '$2$3', $markdown);
+
+        return $markdown;
+    }
+
+    protected function updateLinksInHtml(string $html, string $oldLink, string $newLink): string
+    {
+        if (empty($html)) {
+            return $html;
+        }
+
+        $html = '<body>' . $html . '</body>';
+        libxml_use_internal_errors(true);
+        $doc = new DOMDocument();
+        $doc->loadHTML(mb_convert_encoding($html, 'HTML-ENTITIES', 'UTF-8'));
+
+        $xPath = new DOMXPath($doc);
+        $anchors = $xPath->query('//a[@href]');
+
+        /** @var \DOMElement $anchor */
+        foreach ($anchors as $anchor) {
+            $link = $anchor->getAttribute('href');
+            $updated = str_ireplace($oldLink, $newLink, $link);
+            $anchor->setAttribute('href', $updated);
+        }
+
+        $html = '';
+        $topElems = $doc->documentElement->childNodes->item(0)->childNodes;
+        foreach ($topElems as $child) {
+            $html .= $doc->saveHTML($child);
+        }
+
+        return $html;
+    }
+}

database/migrations/2022_08_17_092941_create_references_table.php

@@ -0,0 +1,34 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+class CreateReferencesTable extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        Schema::create('references', function (Blueprint $table) {
+            $table->id();
+            $table->unsignedInteger('from_id')->index();
+            $table->string('from_type', 25)->index();
+            $table->unsignedInteger('to_id')->index();
+            $table->string('to_type', 25)->index();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        Schema::dropIfExists('references');
+    }
+}

resources/icons/popular.svg

@@ -1,4 +1,3 @@
 <svg viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg">
     <path d="M13.5.67s.74 2.65.74 4.8c0 2.06-1.35 3.73-3.41 3.73-2.07 0-3.63-1.67-3.63-3.73l.03-.36C5.21 7.51 4 10.62 4 14c0 4.42 3.58 8 8 8s8-3.58 8-8C20 8.61 17.41 3.8 13.5.67zM11.71 19c-1.78 0-3.22-1.4-3.22-3.14 0-1.62 1.05-2.76 2.81-3.12 1.77-.36 3.6-1.21 4.62-2.58.39 1.29.59 2.65.59 4.04 0 2.65-2.15 4.8-4.8 4.8z"/>
-    <path d="M0 0h24v24H0z" fill="none"/>
 </svg>

resources/icons/reference.svg

@@ -0,0 +1,3 @@
+<svg viewBox="0 0 48 48" xmlns="http://www.w3.org/2000/svg">
+ <path d="m24 44.15c-0.4 0-0.79167-0.06667-1.175-0.2-0.38333-0.13333-0.70833-0.33333-0.975-0.6l-17.2-17.2c-0.26667-0.26667-0.46667-0.59167-0.6-0.975s-0.2-0.775-0.2-1.175 0.066667-0.79167 0.2-1.175c0.13333-0.38333 0.33333-0.70833 0.6-0.975l17.2-17.2c0.26667-0.26667 0.59167-0.46667 0.975-0.6s0.775-0.2 1.175-0.2 0.79167 0.066667 1.175 0.2c0.38333 0.13333 0.70833 0.33333 0.975 0.6l17.2 17.2c0.26667 0.26667 0.46667 0.59167 0.6 0.975s0.2 0.775 0.2 1.175-0.06667 0.79167-0.2 1.175c-0.13333 0.38333-0.33333 0.70833-0.6 0.975l-17.2 17.2c-0.26667 0.26667-0.59167 0.46667-0.975 0.6s-0.775 0.2-1.175 0.2zm4.05-18.65-5.15 5.15c-0.3 0.3-0.44167 0.65-0.425 1.05 0.01667 0.4 0.175 0.75 0.475 1.05s0.65833 0.45 1.075 0.45 0.775-0.15 1.075-0.45l7.7-7.7c0.3-0.3 0.45-0.65 0.45-1.05s-0.15-0.75-0.45-1.05l-7.75-7.75c-0.3-0.3-0.65-0.45-1.05-0.45s-0.75 0.15-1.05 0.45-0.45 0.65833-0.45 1.075 0.15 0.775 0.45 1.075l5.1 5.15h-12.4c-0.43333 0-0.79167 0.14167-1.075 0.425s-0.425 0.64167-0.425 1.075 0.14167 0.79167 0.425 1.075 0.64167 0.425 1.075 0.425z"/>
+</svg>

resources/lang/en/entities.php

@@ -23,6 +23,7 @@ return [
     'meta_updated' => 'Updated :timeLength',
     'meta_updated_name' => 'Updated :timeLength by :user',
     'meta_owned_name' => 'Owned by :user',
+    'meta_reference_page_count' => 'Referenced on 1 page|Referenced on :count pages',
     'entity_select' => 'Entity Select',
     'entity_select_lack_permission' => 'You don\'t have the required permissions to select this item',
     'images' => 'Images',
@@ -248,6 +249,7 @@ return [
     'pages_edit_content_link' => 'Edit Content',
     'pages_permissions_active' => 'Page Permissions Active',
     'pages_initial_revision' => 'Initial publish',
+    'pages_references_update_revision' => 'System auto-update of internal links',
     'pages_initial_name' => 'New Page',
     'pages_editing_draft_notification' => 'You are currently editing a draft that was last saved :timeDiff.',
     'pages_draft_edited_notification' => 'This page has been updated by since that time. It is recommended that you discard this draft.',
@@ -369,4 +371,9 @@ return [
     'convert_to_book_desc' => 'You can convert this chapter to a new book with the same contents. Any permissions set on this chapter will be copied to the new book but any inherited permissions, from the parent book, will not be copied which could lead to a change of access control.',
     'convert_chapter' => 'Convert Chapter',
     'convert_chapter_confirm' => 'Are you sure you want to convert this chapter?',
+
+    // References
+    'references' => 'References',
+    'references_none' => 'There are no tracked references to this item.',
+    'references_to_desc' => 'Shown below are all the known pages in the system that link to this item.',
 ];

resources/lang/en/settings.php

@@ -89,6 +89,10 @@ return [
     'maint_send_test_email_mail_text' => 'Congratulations! As you received this email notification, your email settings seem to be configured properly.',
     'maint_recycle_bin_desc' => 'Deleted shelves, books, chapters & pages are sent to the recycle bin so they can be restored or permanently deleted. Older items in the recycle bin may be automatically removed after a while depending on system configuration.',
     'maint_recycle_bin_open' => 'Open Recycle Bin',
+    'maint_regen_references' => 'Regenerate References',
+    'maint_regen_references_desc' => 'This action will rebuild the cross-item reference index within the database. This is usually handled automatically but this action can be useful to index old content or content added via unofficial methods.',
+    'maint_regen_references_success' => 'Reference index has been regenerated!',
+    'maint_timeout_command_note' => 'Note: This action can take time to run, which can lead to timeout issues in some web environments. As an alternative, this action be performed using a terminal command.',
 
     // Recycle Bin
     'recycle_bin' => 'Recycle Bin',

resources/views/books/references.blade.php

@@ -0,0 +1,20 @@
+@extends('layouts.simple')
+
+@section('body')
+
+    <div class="container small">
+
+        <div class="my-s">
+            @include('entities.breadcrumbs', ['crumbs' => [
+                $book,
+                $book->getUrl('/references') => [
+                    'text' => trans('entities.references'),
+                    'icon' => 'reference',
+                ]
+            ]])
+        </div>
+
+        @include('entities.references', ['references' => $references])
+    </div>
+
+@stop

resources/views/chapters/references.blade.php

@@ -0,0 +1,21 @@
+@extends('layouts.simple')
+
+@section('body')
+
+    <div class="container small">
+
+        <div class="my-s">
+            @include('entities.breadcrumbs', ['crumbs' => [
+                $chapter->book,
+                $chapter,
+                $chapter->getUrl('/references') => [
+                    'text' => trans('entities.references'),
+                    'icon' => 'reference',
+                ]
+            ]])
+        </div>
+
+        @include('entities.references', ['references' => $references])
+    </div>
+
+@stop

resources/views/entities/meta.blade.php

@@ -59,4 +59,13 @@
             <span title="{{ $entity->updated_at->toDayDateTimeString() }}">{{ trans('entities.meta_updated', ['timeLength' => $entity->updated_at->diffForHumans()]) }}</span>
         </div>
     @endif
+
+    @if($referenceCount ?? 0)
+        <a href="{{ $entity->getUrl('/references') }}" class="entity-meta-item">
+            @icon('reference')
+            <div>
+                {!! trans_choice('entities.meta_reference_page_count', $referenceCount, ['count' => $referenceCount]) !!}
+            </div>
+        </a>
+    @endif
 </div>

resources/views/entities/references.blade.php

@@ -0,0 +1,13 @@
+<main class="card content-wrap">
+    <h1 class="list-heading">{{ trans('entities.references') }}</h1>
+    <p>{{ trans('entities.references_to_desc') }}</p>
+
+    @if(count($references) > 0)
+        <div class="book-contents">
+            @include('entities.list', ['entities' => $references->pluck('from'), 'showPath' => true])
+        </div>
+    @else
+        <p class="text-muted italic">{{ trans('entities.references_none') }}</p>
+    @endif
+
+</main>

resources/views/pages/references.blade.php

@@ -0,0 +1,22 @@
+@extends('layouts.simple')
+
+@section('body')
+
+    <div class="container small">
+
+        <div class="my-s">
+            @include('entities.breadcrumbs', ['crumbs' => [
+                $page->book,
+                $page->chapter,
+                $page,
+                $page->getUrl('/references') => [
+                    'text' => trans('entities.references'),
+                    'icon' => 'reference',
+                ]
+            ]])
+        </div>
+
+        @include('entities.references', ['references' => $references])
+    </div>
+
+@stop

resources/views/settings/maintenance.blade.php

@@ -25,9 +25,10 @@
 
     <div id="image-cleanup" class="card content-wrap auto-height">
         <h2 class="list-heading">{{ trans('settings.maint_image_cleanup') }}</h2>
-        <div class="grid half gap-xl">
+        <div class="grid left-focus gap-xl">
             <div>
                 <p class="small text-muted">{{ trans('settings.maint_image_cleanup_desc') }}</p>
+                <p class="small text-muted italic">{{ trans('settings.maint_timeout_command_note') }}</p>
             </div>
             <div>
                 <form method="POST" action="{{ url('/settings/maintenance/cleanup-images') }}">
@@ -55,7 +56,7 @@
 
     <div id="send-test-email" class="card content-wrap auto-height">
         <h2 class="list-heading">{{ trans('settings.maint_send_test_email') }}</h2>
-        <div class="grid half gap-xl">
+        <div class="grid left-focus gap-xl">
             <div>
                 <p class="small text-muted">{{ trans('settings.maint_send_test_email_desc') }}</p>
             </div>
@@ -68,5 +69,21 @@
         </div>
     </div>
 
+    <div id="regenerate-references" class="card content-wrap auto-height">
+        <h2 class="list-heading">{{ trans('settings.maint_regen_references') }}</h2>
+        <div class="grid left-focus gap-xl">
+            <div>
+                <p class="small text-muted">{{ trans('settings.maint_regen_references_desc') }}</p>
+                <p class="small text-muted italic">{{ trans('settings.maint_timeout_command_note') }}</p>
+            </div>
+            <div>
+                <form method="POST" action="{{ url('/settings/maintenance/regenerate-references') }}">
+                    {!! csrf_field()  !!}
+                    <button class="button outline">{{ trans('settings.maint_regen_references') }}</button>
+                </form>
+            </div>
+        </div>
+    </div>
+
 </div>
 @stop

resources/views/shelves/references.blade.php

@@ -0,0 +1,20 @@
+@extends('layouts.simple')
+
+@section('body')
+
+    <div class="container small">
+
+        <div class="my-s">
+            @include('entities.breadcrumbs', ['crumbs' => [
+                $shelf,
+                $shelf->getUrl('/references') => [
+                    'text' => trans('entities.references'),
+                    'icon' => 'reference',
+                ]
+            ]])
+        </div>
+
+        @include('entities.references', ['references' => $references])
+    </div>
+
+@stop

routes/web.php

@@ -20,6 +20,7 @@ use BookStack\Http\Controllers\PageExportController;
 use BookStack\Http\Controllers\PageRevisionController;
 use BookStack\Http\Controllers\PageTemplateController;
 use BookStack\Http\Controllers\RecycleBinController;
+use BookStack\Http\Controllers\ReferenceController;
 use BookStack\Http\Controllers\RoleController;
 use BookStack\Http\Controllers\SearchController;
 use BookStack\Http\Controllers\SettingController;
@@ -63,6 +64,7 @@ Route::middleware('auth')->group(function () {
     Route::get('/shelves/{slug}/permissions', [BookshelfController::class, 'showPermissions']);
     Route::put('/shelves/{slug}/permissions', [BookshelfController::class, 'permissions']);
     Route::post('/shelves/{slug}/copy-permissions', [BookshelfController::class, 'copyPermissions']);
+    Route::get('/shelves/{slug}/references', [ReferenceController::class, 'shelf']);
 
     // Book Creation
     Route::get('/shelves/{shelfSlug}/create-book', [BookController::class, 'create']);
@@ -85,6 +87,7 @@ Route::middleware('auth')->group(function () {
     Route::post('/books/{bookSlug}/convert-to-shelf', [BookController::class, 'convertToShelf']);
     Route::get('/books/{bookSlug}/sort', [BookSortController::class, 'show']);
     Route::put('/books/{bookSlug}/sort', [BookSortController::class, 'update']);
+    Route::get('/books/{slug}/references', [ReferenceController::class, 'book']);
     Route::get('/books/{bookSlug}/export/html', [BookExportController::class, 'html']);
     Route::get('/books/{bookSlug}/export/pdf', [BookExportController::class, 'pdf']);
     Route::get('/books/{bookSlug}/export/markdown', [BookExportController::class, 'markdown']);
@@ -110,6 +113,7 @@ Route::middleware('auth')->group(function () {
     Route::get('/books/{bookSlug}/draft/{pageId}/delete', [PageController::class, 'showDeleteDraft']);
     Route::get('/books/{bookSlug}/page/{pageSlug}/permissions', [PageController::class, 'showPermissions']);
     Route::put('/books/{bookSlug}/page/{pageSlug}/permissions', [PageController::class, 'permissions']);
+    Route::get('/books/{bookSlug}/page/{pageSlug}/references', [ReferenceController::class, 'page']);
     Route::put('/books/{bookSlug}/page/{pageSlug}', [PageController::class, 'update']);
     Route::delete('/books/{bookSlug}/page/{pageSlug}', [PageController::class, 'destroy']);
     Route::delete('/books/{bookSlug}/draft/{pageId}', [PageController::class, 'destroyDraft']);
@@ -140,6 +144,7 @@ Route::middleware('auth')->group(function () {
     Route::get('/books/{bookSlug}/chapter/{chapterSlug}/export/markdown', [ChapterExportController::class, 'markdown']);
     Route::get('/books/{bookSlug}/chapter/{chapterSlug}/export/plaintext', [ChapterExportController::class, 'plainText']);
     Route::put('/books/{bookSlug}/chapter/{chapterSlug}/permissions', [ChapterController::class, 'permissions']);
+    Route::get('/books/{bookSlug}/chapter/{chapterSlug}/references', [ReferenceController::class, 'chapter']);
     Route::get('/books/{bookSlug}/chapter/{chapterSlug}/delete', [ChapterController::class, 'showDelete']);
     Route::delete('/books/{bookSlug}/chapter/{chapterSlug}', [ChapterController::class, 'destroy']);
 
@@ -213,6 +218,7 @@ Route::middleware('auth')->group(function () {
     Route::get('/settings/maintenance', [MaintenanceController::class, 'index']);
     Route::delete('/settings/maintenance/cleanup-images', [MaintenanceController::class, 'cleanupImages']);
     Route::post('/settings/maintenance/send-test-email', [MaintenanceController::class, 'sendTestEmail']);
+    Route::post('/settings/maintenance/regenerate-references', [MaintenanceController::class, 'regenerateReferences']);
 
     // Recycle Bin
     Route::get('/settings/recycle-bin', [RecycleBinController::class, 'index']);

tests/Commands/RegenerateReferencesCommandTest.php

@@ -0,0 +1,32 @@
+<?php
+
+namespace Tests\Commands;
+
+use BookStack\Entities\Models\Page;
+use Illuminate\Support\Facades\DB;
+use Tests\TestCase;
+
+class RegenerateReferencesCommandTest extends TestCase
+{
+    public function test_regenerate_references_command()
+    {
+        /** @var Page $page */
+        $page = Page::query()->first();
+        $book = $page->book;
+
+        $page->html = '<a href="' . $book->getUrl() . '">Book Link</a>';
+        $page->save();
+
+        DB::table('references')->delete();
+
+        $this->artisan('bookstack:regenerate-references')
+            ->assertExitCode(0);
+
+        $this->assertDatabaseHas('references', [
+            'from_id' => $page->id,
+            'from_type' => $page->getMorphClass(),
+            'to_id' => $book->id,
+            'to_type' => $book->getMorphClass(),
+        ]);
+    }
+}

tests/References/CrossLinkParserTest.php

@@ -0,0 +1,62 @@
+<?php
+
+namespace Tests\References;
+
+use BookStack\Entities\Models\Book;
+use BookStack\Entities\Models\Page;
+use BookStack\References\CrossLinkParser;
+use Tests\TestCase;
+
+class CrossLinkParserTest extends TestCase
+{
+
+    public function test_instance_with_entity_resolvers_matches_entity_links()
+    {
+        $entities = $this->getEachEntityType();
+        $otherPage = Page::query()->where('id', '!=', $entities['page']->id)->first();
+
+        $html = '
+<a href="' . url('/link/' . $otherPage->id) . '#cat">Page Permalink</a>
+<a href="' . $entities['page'] ->getUrl(). '?a=b">Page Link</a>
+<a href="' . $entities['chapter']->getUrl() . '?cat=mouse#donkey">Chapter Link</a>
+<a href="' . $entities['book']->getUrl() . '/edit">Book Link</a>
+<a href="' . $entities['bookshelf']->getUrl() . '/edit?cat=happy#hello">Shelf Link</a>
+<a href="' . url('/settings') . '">Settings Link</a>
+        ';
+
+        $parser = CrossLinkParser::createWithEntityResolvers();
+        $results = $parser->extractLinkedModels($html);
+
+        $this->assertCount(5, $results);
+        $this->assertEquals(get_class($otherPage), get_class($results[0]));
+        $this->assertEquals($otherPage->id, $results[0]->id);
+        $this->assertEquals(get_class($entities['page']), get_class($results[1]));
+        $this->assertEquals($entities['page']->id, $results[1]->id);
+        $this->assertEquals(get_class($entities['chapter']), get_class($results[2]));
+        $this->assertEquals($entities['chapter']->id, $results[2]->id);
+        $this->assertEquals(get_class($entities['book']), get_class($results[3]));
+        $this->assertEquals($entities['book']->id, $results[3]->id);
+        $this->assertEquals(get_class($entities['bookshelf']), get_class($results[4]));
+        $this->assertEquals($entities['bookshelf']->id, $results[4]->id);
+    }
+
+    public function test_similar_page_and_book_reference_links_dont_conflict()
+    {
+        $page = Page::query()->first();
+        $book = $page->book;
+
+        $html = '
+<a href="' . $page->getUrl() . '">Page Link</a>
+<a href="' . $book->getUrl() . '">Book Link</a>
+        ';
+
+        $parser = CrossLinkParser::createWithEntityResolvers();
+        $results = $parser->extractLinkedModels($html);
+
+        $this->assertCount(2, $results);
+        $this->assertEquals(get_class($page), get_class($results[0]));
+        $this->assertEquals($page->id, $results[0]->id);
+        $this->assertEquals(get_class($book), get_class($results[1]));
+        $this->assertEquals($book->id, $results[1]->id);
+    }
+}

tests/References/ReferencesTest.php

@@ -0,0 +1,188 @@
+<?php
+
+namespace Tests\References;
+
+use BookStack\Entities\Models\Book;
+use BookStack\Entities\Models\Page;
+use BookStack\Entities\Repos\PageRepo;
+use BookStack\Entities\Tools\TrashCan;
+use BookStack\Model;
+use BookStack\References\Reference;
+use Tests\TestCase;
+
+class ReferencesTest extends TestCase
+{
+
+    public function test_references_created_on_page_update()
+    {
+        /** @var Page $pageA */
+        /** @var Page $pageB */
+        $pageA = Page::query()->first();
+        $pageB = Page::query()->where('id', '!=', $pageA->id)->first();
+
+        $this->assertDatabaseMissing('references', ['from_id' => $pageA->id, 'from_type' => $pageA->getMorphClass()]);
+
+        $this->asEditor()->put($pageA->getUrl(), [
+            'name' => 'Reference test',
+            'html' => '<a href="' . $pageB->getUrl() . '">Testing</a>'
+        ]);
+
+        $this->assertDatabaseHas('references', [
+            'from_id' => $pageA->id,
+            'from_type' => $pageA->getMorphClass(),
+            'to_id' => $pageB->id,
+            'to_type' => $pageB->getMorphClass(),
+        ]);
+    }
+
+    public function test_references_deleted_on_entity_delete()
+    {
+        /** @var Page $pageA */
+        /** @var Page $pageB */
+        $pageA = Page::query()->first();
+        $pageB = Page::query()->where('id', '!=', $pageA->id)->first();
+
+        $this->createReference($pageA, $pageB);
+        $this->createReference($pageB, $pageA);
+
+        $this->assertDatabaseHas('references', ['from_id' => $pageA->id, 'from_type' => $pageA->getMorphClass()]);
+        $this->assertDatabaseHas('references', ['to_id' => $pageA->id, 'to_type' => $pageA->getMorphClass()]);
+
+        app(PageRepo::class)->destroy($pageA);
+        app(TrashCan::class)->empty();
+
+        $this->assertDatabaseMissing('references', ['from_id' => $pageA->id, 'from_type' => $pageA->getMorphClass()]);
+        $this->assertDatabaseMissing('references', ['to_id' => $pageA->id, 'to_type' => $pageA->getMorphClass()]);
+    }
+
+    public function test_references_to_count_visible_on_entity_show_view()
+    {
+        $entities = $this->getEachEntityType();
+        /** @var Page $otherPage */
+        $otherPage = Page::query()->where('id', '!=', $entities['page']->id)->first();
+
+        $this->asEditor();
+        foreach ($entities as $entity) {
+            $this->createReference($entities['page'], $entity);
+        }
+
+        foreach ($entities as $entity) {
+            $resp = $this->get($entity->getUrl());
+            $resp->assertSee('Referenced on 1 page');
+            $resp->assertDontSee('Referenced on 1 pages');
+        }
+
+        $this->createReference($otherPage, $entities['page']);
+        $resp = $this->get($entities['page']->getUrl());
+        $resp->assertSee('Referenced on 2 pages');
+    }
+
+    public function test_references_to_visible_on_references_page()
+    {
+        $entities = $this->getEachEntityType();
+        $this->asEditor();
+        foreach ($entities as $entity) {
+            $this->createReference($entities['page'], $entity);
+        }
+
+        foreach ($entities as $entity) {
+            $resp = $this->get($entity->getUrl('/references'));
+            $resp->assertSee('References');
+            $resp->assertSee($entities['page']->name);
+            $resp->assertDontSee('There are no tracked references');
+        }
+    }
+
+    public function test_reference_not_visible_if_view_permission_does_not_permit()
+    {
+        /** @var Page $page */
+        /** @var Page $pageB */
+        $page = Page::query()->first();
+        $pageB = Page::query()->where('id', '!=', $page->id)->first();
+        $this->createReference($pageB, $page);
+
+        $this->setEntityRestrictions($pageB);
+
+        $this->asEditor()->get($page->getUrl('/references'))->assertDontSee($pageB->name);
+        $this->asAdmin()->get($page->getUrl('/references'))->assertSee($pageB->name);
+    }
+
+    public function test_reference_page_shows_empty_state_with_no_references()
+    {
+        /** @var Page $page */
+        $page = Page::query()->first();
+
+        $this->asEditor()
+            ->get($page->getUrl('/references'))
+            ->assertSee('There are no tracked references');
+    }
+
+    public function test_pages_leading_to_entity_updated_on_url_change()
+    {
+        /** @var Page $pageA */
+        /** @var Page $pageB */
+        /** @var Book $book */
+        $pageA = Page::query()->first();
+        $pageB = Page::query()->where('id', '!=', $pageA->id)->first();
+        $book = Book::query()->first();
+
+        foreach ([$pageA, $pageB] as $page) {
+            $page->html = '<a href="' . $book->getUrl() . '">Link</a>';
+            $page->save();
+            $this->createReference($page, $book);
+        }
+
+        $this->asEditor()->put($book->getUrl(), [
+            'name' => 'my updated book slugaroo',
+        ]);
+
+        foreach ([$pageA, $pageB] as $page) {
+            $page->refresh();
+            $this->assertStringContainsString('href="http://localhost/books/my-updated-book-slugaroo"', $page->html);
+            $this->assertDatabaseHas('page_revisions', [
+                'page_id' => $page->id,
+                'summary' => 'System auto-update of internal links'
+            ]);
+        }
+    }
+
+    public function test_markdown_links_leading_to_entity_updated_on_url_change()
+    {
+        /** @var Page $page */
+        /** @var Book $book */
+        $page = Page::query()->first();
+        $book = Book::query()->first();
+
+        $bookUrl = $book->getUrl();
+        $markdown = '
+        [An awesome link](' . $bookUrl . ')
+        [An awesome link with query & hash](' . $bookUrl . '?test=yes#cats)
+        [An awesome link with path](' . $bookUrl . '/an/extra/trail)
+        [An awesome link with title](' . $bookUrl . ' "title")
+        [ref]: ' . $bookUrl . '?test=yes#dogs
+        [ref_without_space]:' . $bookUrl . '
+        [ref_with_title]: ' . $bookUrl . ' "title"';
+        $page->markdown = $markdown;
+        $page->save();
+        $this->createReference($page, $book);
+
+        $this->asEditor()->put($book->getUrl(), [
+            'name' => 'my updated book slugadoo',
+        ]);
+
+        $page->refresh();
+        $expected = str_replace($bookUrl, 'http://localhost/books/my-updated-book-slugadoo', $markdown);
+        $this->assertEquals($expected, $page->markdown);
+    }
+
+    protected function createReference(Model $from, Model $to)
+    {
+        (new Reference())->forceFill([
+            'from_type' => $from->getMorphClass(),
+            'from_id' => $from->id,
+            'to_type' => $to->getMorphClass(),
+            'to_id' => $to->id,
+        ])->save();
+    }
+
+}

tests/Settings/RecycleBinTest.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Tests;
+namespace Tests\Settings;
 
 use BookStack\Entities\Models\Book;
 use BookStack\Entities\Models\Bookshelf;
@@ -10,6 +10,7 @@ use BookStack\Entities\Models\Entity;
 use BookStack\Entities\Models\Page;
 use Illuminate\Support\Carbon;
 use Illuminate\Support\Facades\DB;
+use Tests\TestCase;
 
 class RecycleBinTest extends TestCase
 {

tests/Settings/RegenerateReferencesTest.php

@@ -0,0 +1,55 @@
+<?php
+
+namespace Tests\Settings;
+
+use BookStack\Actions\ActivityType;
+use BookStack\References\ReferenceStore;
+use Tests\TestCase;
+
+class RegenerateReferencesTest extends TestCase
+{
+    public function test_option_visible_on_maintenance_page()
+    {
+        $pageView = $this->asAdmin()->get('/settings/maintenance');
+        $formCssSelector = 'form[action$="/settings/maintenance/regenerate-references"]';
+        $html = $this->withHtml($pageView);
+        $html->assertElementExists('#regenerate-references');
+        $html->assertElementExists($formCssSelector);
+        $html->assertElementContains($formCssSelector . ' button', 'Regenerate References');
+    }
+
+    public function test_action_runs_reference_regen()
+    {
+        $this->mock(ReferenceStore::class)
+            ->shouldReceive('updateForAllPages')
+            ->once();
+
+        $resp = $this->asAdmin()->post('/settings/maintenance/regenerate-references');
+        $resp->assertRedirect('/settings/maintenance#regenerate-references');
+        $this->assertSessionHas('success', 'Reference index has been regenerated!');
+        $this->assertActivityExists(ActivityType::MAINTENANCE_ACTION_RUN, null, 'regenerate-references');
+    }
+
+    public function test_settings_manage_permission_required()
+    {
+        $editor = $this->getEditor();
+        $resp = $this->actingAs($editor)->post('/settings/maintenance/regenerate-references');
+        $this->assertPermissionError($resp);
+
+        $this->giveUserPermissions($editor, ['settings-manage']);
+
+        $resp = $this->actingAs($editor)->post('/settings/maintenance/regenerate-references');
+        $this->assertNotPermissionError($resp);
+    }
+
+    public function test_action_failed_shown_as_error_notification()
+    {
+        $this->mock(ReferenceStore::class)
+            ->shouldReceive('updateForAllPages')
+            ->andThrow(\Exception::class, 'A badger stopped the task');
+
+        $resp = $this->asAdmin()->post('/settings/maintenance/regenerate-references');
+        $resp->assertRedirect('/settings/maintenance#regenerate-references');
+        $this->assertSessionError('A badger stopped the task');
+    }
+}

tests/Settings/TestEmailTest.php

@@ -1,10 +1,11 @@
 <?php
 
-namespace Tests;
+namespace Tests\Settings;
 
 use BookStack\Notifications\TestEmail;
 use Illuminate\Contracts\Notifications\Dispatcher;
 use Illuminate\Support\Facades\Notification;
+use Tests\TestCase;
 
 class TestEmailTest extends TestCase
 {

tests/TestCase.php

@@ -430,7 +430,7 @@ abstract class TestCase extends BaseTestCase
     }
 
     /**
-     * @return Entity[]
+     * @return array{page: Page, chapter: Chapter, book: Book, bookshelf: Bookshelf}
      */
     protected function getEachEntityType(): array
     {