Added page content parsing to up-rank header text in search

This adds parsing of page content so that headers apply a boost to
scores in the search term index.
Additionally, this merges title and content terms to reduce the amount
of stored terms a little.
Includes testing to cover.

app/Entities/Models/Book.php

@@ -24,7 +24,7 @@ class Book extends Entity implements HasCoverImage
 {
     use HasFactory;
 
-    public $searchFactor = 2;
+    public $searchFactor = 1.5;
 
     protected $fillable = ['name', 'description'];
     protected $hidden = ['restricted', 'pivot', 'image_id', 'deleted_at'];

app/Entities/Models/Bookshelf.php

@@ -13,7 +13,7 @@ class Bookshelf extends Entity implements HasCoverImage
 
     protected $table = 'bookshelves';
 
-    public $searchFactor = 3;
+    public $searchFactor = 1.5;
 
     protected $fillable = ['name', 'description', 'image_id'];
 

app/Entities/Models/Chapter.php

@@ -16,7 +16,7 @@ class Chapter extends BookChild
 {
     use HasFactory;
 
-    public $searchFactor = 1.3;
+    public $searchFactor = 1.5;
 
     protected $fillable = ['name', 'description', 'priority', 'book_id'];
     protected $hidden = ['restricted', 'pivot', 'deleted_at'];

app/Entities/Models/Entity.php

@@ -238,20 +238,12 @@ abstract class Entity extends Model implements Sluggable, Favouritable, Viewable
         return mb_substr($this->name, 0, $length - 3) . '...';
     }
 
-    /**
-     * Get the body text of this entity.
-     */
-    public function getText(): string
-    {
-        return $this->{$this->textField} ?? '';
-    }
-
     /**
      * Get an excerpt of this entity's descriptive content to the specified length.
      */
     public function getExcerpt(int $length = 100): string
     {
-        $text = $this->getText();
+        $text = $this->{$this->textField} ?? '';
 
         if (mb_strlen($text) > $length) {
             $text = mb_substr($text, 0, $length - 3) . '...';

app/Entities/Models/Page.php

@@ -3,13 +3,13 @@
 namespace BookStack\Entities\Models;
 
 use BookStack\Entities\Tools\PageContent;
+use BookStack\Facades\Permissions;
 use BookStack\Uploads\Attachment;
 use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Collection;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Database\Eloquent\Relations\HasMany;
-use Permissions;
 
 /**
  * Class Page.
@@ -64,10 +64,8 @@ class Page extends BookChild
 
     /**
      * Check if this page has a chapter.
-     *
-     * @return bool
      */
-    public function hasChapter()
+    public function hasChapter(): bool
     {
         return $this->chapter()->count() > 0;
     }

app/Entities/Repos/PageRepo.php

@@ -157,8 +157,8 @@ class PageRepo
      */
     public function publishDraft(Page $draft, array $input): Page
     {
-        $this->baseRepo->update($draft, $input);
         $this->updateTemplateStatusAndContentFromInput($draft, $input);
+        $this->baseRepo->update($draft, $input);
 
         $draft->draft = false;
         $draft->revision_count = 1;

app/Entities/Tools/SearchIndex.php

@@ -4,7 +4,10 @@ namespace BookStack\Entities\Tools;
 
 use BookStack\Entities\EntityProvider;
 use BookStack\Entities\Models\Entity;
+use BookStack\Entities\Models\Page;
 use BookStack\Entities\Models\SearchTerm;
+use DOMDocument;
+use DOMNode;
 use Illuminate\Support\Collection;
 
 class SearchIndex
@@ -64,7 +67,8 @@ class SearchIndex
         SearchTerm::query()->truncate();
 
         foreach ($this->entityProvider->all() as $entityModel) {
-            $selectFields = ['id', 'name', $entityModel->textField];
+            $indexContentField = $entityModel instanceof Page ? 'html' : 'description';
+            $selectFields = ['id', 'name', $indexContentField];
             $total = $entityModel->newQuery()->withTrashed()->count();
             $chunkSize = 250;
             $processed = 0;
@@ -93,11 +97,70 @@ class SearchIndex
     }
 
     /**
-     * Create a scored term array from the given text.
+     * Create a scored term array from the given text, where the keys are the terms
+     * and the values are their scores.
      *
-     * @returns array{term: string, score: float}
+     * @returns array<string, int>
      */
-    protected function generateTermArrayFromText(string $text, int $scoreAdjustment = 1): array
+    protected function generateTermScoreMapFromText(string $text, int $scoreAdjustment = 1): array
+    {
+        $termMap = $this->textToTermCountMap($text);
+
+        foreach ($termMap as $term => $count) {
+            $termMap[$term] = $count * $scoreAdjustment;
+        }
+
+        return $termMap;
+    }
+
+    /**
+     * Create a scored term array from the given HTML, where the keys are the terms
+     * and the values are their scores.
+     *
+     * @returns array<string, int>
+     */
+    protected function generateTermScoreMapFromHtml(string $html): array
+    {
+        if (empty($html)) {
+            return [];
+        }
+
+        $scoresByTerm = [];
+        $elementScoreAdjustmentMap = [
+            'h1' => 10,
+            'h2' => 5,
+            'h3' => 4,
+            'h4' => 3,
+            'h5' => 2,
+            'h6' => 1.5,
+        ];
+
+        $html = '<body>' . $html . '</body>';
+        libxml_use_internal_errors(true);
+        $doc = new DOMDocument();
+        $doc->loadHTML(mb_convert_encoding($html, 'HTML-ENTITIES', 'UTF-8'));
+
+        $topElems = $doc->documentElement->childNodes->item(0)->childNodes;
+        /** @var DOMNode $child */
+        foreach ($topElems as $child) {
+            $nodeName = $child->nodeName;
+            $termCounts = $this->textToTermCountMap(trim($child->textContent));
+            foreach ($termCounts as $term => $count) {
+                $scoreChange = $count * ($elementScoreAdjustmentMap[$nodeName] ?? 1);
+                $scoresByTerm[$term] = ($scoresByTerm[$term] ?? 0) + $scoreChange;
+            }
+        }
+
+        return $scoresByTerm;
+    }
+
+    /**
+     * For the given text, return an array where the keys are the unique term words
+     * and the values are the frequency of that term.
+     *
+     * @returns array<string, int>
+     */
+    protected function textToTermCountMap(string $text): array
     {
         $tokenMap = []; // {TextToken => OccurrenceCount}
         $splitChars = " \n\t.,!?:;()[]{}<>`'\"";
@@ -111,34 +174,61 @@ class SearchIndex
             $token = strtok($splitChars);
         }
 
-        $terms = [];
-        foreach ($tokenMap as $token => $count) {
-            $terms[] = [
-                'term'  => $token,
-                'score' => $count * $scoreAdjustment,
-            ];
-        }
-
-        return $terms;
+        return $tokenMap;
     }
 
     /**
      * For the given entity, Generate an array of term data details.
      * Is the raw term data, not instances of SearchTerm models.
      *
-     * @returns array{term: string, score: float}[]
+     * @returns array{term: string, score: float, entity_id: int, entity_type: string}[]
      */
     protected function entityToTermDataArray(Entity $entity): array
     {
-        $nameTerms = $this->generateTermArrayFromText($entity->name, 40 * $entity->searchFactor);
-        $bodyTerms = $this->generateTermArrayFromText($entity->getText(), 1 * $entity->searchFactor);
-        $termData = array_merge($nameTerms, $bodyTerms);
+        $nameTermsMap = $this->generateTermScoreMapFromText($entity->name, 40 * $entity->searchFactor);
 
-        foreach ($termData as $index => $term) {
-            $termData[$index]['entity_type'] = $entity->getMorphClass();
-            $termData[$index]['entity_id'] = $entity->id;
+        if ($entity instanceof Page) {
+            $bodyTermsMap = $this->generateTermScoreMapFromHtml($entity->html);
+        } else {
+            $bodyTermsMap = $this->generateTermScoreMapFromText($entity->description, $entity->searchFactor);
         }
 
-        return $termData;
+        $mergedScoreMap = $this->mergeTermScoreMaps($nameTermsMap, $bodyTermsMap);
+
+        $dataArray = [];
+        $entityId = $entity->id;
+        $entityType = $entity->getMorphClass();
+        foreach ($mergedScoreMap as $term => $score) {
+            $dataArray[] = [
+                'term' => $term,
+                'score' => $score,
+                'entity_type' => $entityType,
+                'entity_id' => $entityId,
+            ];
+        }
+
+        return $dataArray;
+    }
+
+
+    /**
+     * For the given term data arrays, Merge their contents by term
+     * while combining any scores.
+     *
+     * @param array<string, int>[] ...$scoreMaps
+     *
+     * @returns array<string, int>
+     */
+    protected function mergeTermScoreMaps(...$scoreMaps): array
+    {
+        $mergedMap = [];
+
+        foreach ($scoreMaps as $scoreMap) {
+            foreach ($scoreMap as $term => $score) {
+                $mergedMap[$term] = ($mergedMap[$term] ?? 0) + $score;
+            }
+        }
+
+        return $mergedMap;
     }
 }

tests/Entity/EntitySearchTest.php

@@ -7,6 +7,7 @@ use BookStack\Entities\Models\Book;
 use BookStack\Entities\Models\Bookshelf;
 use BookStack\Entities\Models\Chapter;
 use BookStack\Entities\Models\Page;
+use BookStack\Entities\Models\SearchTerm;
 use Tests\TestCase;
 
 class EntitySearchTest extends TestCase
@@ -320,4 +321,43 @@ class EntitySearchTest extends TestCase
         $search->assertElementContains('.entity-list > .page', 'Test page B', 1);
         $search->assertElementContains('.entity-list > .page', 'Test page A', 2);
     }
+
+    public function test_terms_in_headers_have_an_adjusted_index_score()
+    {
+        $page = $this->newPage(['name' => 'Test page A', 'html' => '
+            <p>TermA</p>
+            <h1>TermB <strong>TermNested</strong></h1>
+            <h2>TermC</h2>
+            <h3>TermD</h3>
+            <h4>TermE</h4>
+            <h5>TermF</h5>
+            <h6>TermG</h6>
+        ']);
+
+        $entityRelationCols = ['entity_id' => $page->id, 'entity_type' => 'BookStack\\Page'];
+        $scoreByTerm = SearchTerm::query()->where($entityRelationCols)->pluck('score', 'term');
+
+        $this->assertEquals(1, $scoreByTerm->get('TermA'));
+        $this->assertEquals(10, $scoreByTerm->get('TermB'));
+        $this->assertEquals(10, $scoreByTerm->get('TermNested'));
+        $this->assertEquals(5, $scoreByTerm->get('TermC'));
+        $this->assertEquals(4, $scoreByTerm->get('TermD'));
+        $this->assertEquals(3, $scoreByTerm->get('TermE'));
+        $this->assertEquals(2, $scoreByTerm->get('TermF'));
+        // Is 1.5 but stored as integer, rounding up
+        $this->assertEquals(2, $scoreByTerm->get('TermG'));
+    }
+
+    public function test_name_and_content_terms_are_merged_to_single_score()
+    {
+        $page = $this->newPage(['name' => 'TermA', 'html' => '
+            <p>TermA</p>
+        ']);
+
+        $entityRelationCols = ['entity_id' => $page->id, 'entity_type' => 'BookStack\\Page'];
+        $scoreByTerm = SearchTerm::query()->where($entityRelationCols)->pluck('score', 'term');
+
+        // Scores 40 for being in the name then 1 for being in the content
+        $this->assertEquals(41, $scoreByTerm->get('TermA'));
+    }
 }