Verify: index files several at a time over SFTP, pack folders listed, progress stored and shown

lib/Backend/GetsOneByOne.php

@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+// SPDX-FileCopyrightText: 2026 Dillard Blom
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+namespace OCA\NgBackup\Backend;
+
+/** IBackend::getMany() for a backend where reading files one after the other costs nothing extra. */
+trait GetsOneByOne {
+	/**
+	 * @param list<string> $paths
+	 * @return \Generator<string, string>
+	 */
+	public function getMany(array $paths): \Generator {
+		foreach ($paths as $path) {
+			$fh = $this->get($path);
+			try {
+				$data = stream_get_contents($fh);
+			} finally {
+				fclose($fh);
+			}
+			if ($data === false) {
+				throw new BackendException('Read failed for ' . $path);
+			}
+			yield $path => $data;
+		}
+	}
+}