albums: fix empty root check

Signed-off-by: Varun Patil <varunpatil@ucla.edu>

lib/ClustersBackend/AlbumsBackend.php

@@ -24,6 +24,7 @@ declare(strict_types=1);
 namespace OCA\Memories\ClustersBackend;
 
 use OCA\Memories\Db\AlbumsQuery;
+use OCA\Memories\Db\TimelineQuery;
 use OCA\Memories\Exceptions;
 use OCA\Memories\Util;
 use OCP\IRequest;
@@ -32,13 +33,16 @@ class AlbumsBackend extends Backend
 {
     protected AlbumsQuery $albumsQuery;
     protected IRequest $request;
+    protected TimelineQuery $tq;
 
     public function __construct(
         AlbumsQuery $albumsQuery,
-        IRequest $request
+        IRequest $request,
+        TimelineQuery $tq
     ) {
         $this->albumsQuery = $albumsQuery;
         $this->request = $request;
+        $this->tq = $tq;
     }
 
     public static function appName(): string
@@ -78,6 +82,9 @@ class AlbumsBackend extends Backend
             $query->expr()->eq('paf.album_id', $query->createNamedParameter($album['album_id'])),
             $query->expr()->eq('paf.file_id', 'm.fileid'),
         ));
+
+        // Since we joined to the album, otherwise this is unsafe
+        $this->tq->allowEmptyRoot();
     }
 
     public function getClusters(): array

lib/Db/TimelineQuery.php

@@ -24,7 +24,8 @@ class TimelineQuery
 
     protected IDBConnection $connection;
     protected IRequest $request;
-    private ?TimelineRoot $_root = null;
+    protected ?TimelineRoot $_root = null;
+    protected bool $_rootEmptyAllowed = false;
 
     public function __construct(IDBConnection $connection, IRequest $request)
     {
@@ -32,16 +33,29 @@ class TimelineQuery
         $this->request = $request;
     }
 
-    public function root(): TimelineRoot
+    public function root(?TimelineRoot $override = null): TimelineRoot
     {
+        if (null !== $override) {
+            $this->_root = $override;
+        }
+
         if (null === $this->_root) {
             $this->_root = new TimelineRoot();
             $this->_root->populate();
         }
 
+        if (!$this->_rootEmptyAllowed && $this->_root->isEmpty()) {
+            throw new \Exception('No valid root folder found (.nomedia?)');
+        }
+
         return $this->_root;
     }
 
+    public function allowEmptyRoot(bool $value = true)
+    {
+        $this->_rootEmptyAllowed = $value;
+    }
+
     public function getBuilder()
     {
         return $this->connection->getQueryBuilder();

lib/Db/TimelineQueryDays.php

@@ -35,7 +35,6 @@ trait TimelineQueryDays
         $query->select('m.dayid', $count)
             ->from('memories', 'm')
         ;
-        $query = $this->joinFilecache($query, null, $recursive, $archive);
 
         // Group and sort by dayid
         $query->groupBy('m.dayid')
@@ -45,9 +44,11 @@ trait TimelineQueryDays
         // Apply all transformations
         $this->applyAllTransforms($queryTransforms, $query, true);
 
-        $cursor = $this->executeQueryWithCTEs($query);
-        $rows = $cursor->fetchAll();
-        $cursor->closeCursor();
+        // JOIN with filecache for existing files
+        $query = $this->joinFilecache($query, null, $recursive, $archive);
+
+        // FETCH all days
+        $rows = $this->executeQueryWithCTEs($query)->fetchAll();
 
         return $this->processDays($rows);
     }
@@ -82,9 +83,6 @@ trait TimelineQueryDays
             ->from('memories', 'm')
         ;
 
-        // JOIN with filecache for existing files
-        $query = $this->joinFilecache($query, null, $recursive, $archive);
-
         // JOIN with mimetypes to get the mimetype
         $query->join('f', 'mimetypes', 'mimetypes', $query->expr()->eq('f.mimetype', 'mimetypes.id'));
 
@@ -106,6 +104,9 @@ trait TimelineQueryDays
         // Apply all transformations
         $this->applyAllTransforms($queryTransforms, $query, false);
 
+        // JOIN with filecache for existing files
+        $query = $this->joinFilecache($query, null, $recursive, $archive);
+
         // FETCH all photos in this day
         $day = $this->executeQueryWithCTEs($query)->fetchAll();
 
@@ -150,14 +151,8 @@ trait TimelineQueryDays
         bool $recursive = true,
         bool $archive = false
     ): IQueryBuilder {
-        if (null === $root) {
-            $root = $this->root();
-        }
-
-        // Never join against an empty root
-        if (!$root || $root->isEmpty()) {
-            throw new \InvalidArgumentException('Timeline root is empty');
-        }
+        // This will throw if the root is illegally empty
+        $root = $this->root($root);
 
         // Join with memories
         $baseOp = $query->expr()->eq('f.fileid', 'm.fileid');