delete filecache entries when the object doesn't exist

lib/private/Files/ObjectStore/ObjectStoreStorage.php

@@ -323,14 +323,16 @@
 			case 'rb':
 				$stat = $this->stat($path);
 				if (is_array($stat)) {
+					$urn = $this->getURN($stat['fileid']);
+
 					$filesize = $stat['size'] ?? 0;
 					// Reading 0 sized files is a waste of time
 					if ($filesize === 0) {
 						return fopen('php://memory', $mode);
 					}
 
 					try {
-						$handle = $this->objectStore->readObject($this->getURN($stat['fileid']));
+						$handle = $this->objectStore->readObject($urn);
 						if ($handle === false) {
 							return false; // keep backward compatibility
 						}
@@ -343,13 +345,15 @@
 					} catch (NotFoundException $e) {
 						$this->logger->logException($e, [
 							'app' => 'objectstore',
-							'message' => 'Could not get object ' . $this->getURN($stat['fileid']) . ' for file ' . $path,
+							'message' => 'Could not get object ' . $urn . ' for file ' . $path,
 						]);
+						$this->logger->warning("removing filecache entry for object that doesn't seem to exist on the object store. " . json_encode($stat));
+						$this->getCache()->remove((int)$stat['fileid']);
 						throw $e;
 					} catch (\Exception $ex) {
 						$this->logger->logException($ex, [
 							'app' => 'objectstore',
-							'message' => 'Could not get object ' . $this->getURN($stat['fileid']) . ' for file ' . $path,
+							'message' => 'Could not get object ' . $urn . ' for file ' . $path,
 						]);
 						return false;
 					}

lib/private/Files/ObjectStore/S3ObjectTrait.php

@@ -33,6 +33,7 @@
 use GuzzleHttp\Psr7;
 use GuzzleHttp\Psr7\Utils;
 use OC\Files\Stream\SeekableHttpStream;
+use OCP\Files\NotFoundException;
 use Psr\Http\Message\StreamInterface;
 
 trait S3ObjectTrait {
@@ -87,7 +88,11 @@ public function readObject($urn) {
 			}
 
 			$context = stream_context_create($opts);
-			return fopen($request->getUri(), 'r', false, $context);
+			$fh = fopen($request->getUri(), 'r', false, $context);
+			if (!$fh && isset($http_response_header[0]) && str_contains($http_response_header[0], '404')) {
+				throw new NotFoundException("object $urn not found in object store bucket " . $this->getBucket());
+			}
+			return $fh;
 		});
 		if (!$fh) {
 			throw new \Exception("Failed to read object $urn");