1 files changed, 95 insertions, 0 deletions
diff --git a/apps/dav/lib/Paginate/PaginatePlugin.php b/apps/dav/lib/Paginate/PaginatePlugin.php
new file mode 100644
index 00000000000..c02eb9f21eb
--- /dev/null
+++ b/apps/dav/lib/Paginate/PaginatePlugin.php
@@ -0,0 +1,95 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+namespace OCA\DAV\Paginate;
+
+use Sabre\DAV\Server;
+use Sabre\DAV\ServerPlugin;
+use Sabre\HTTP\RequestInterface;
+use Sabre\HTTP\ResponseInterface;
+
+class PaginatePlugin extends ServerPlugin {
+	public const PAGINATE_HEADER = 'X-NC-Paginate';
+	public const PAGINATE_TOTAL_HEADER = 'X-NC-Paginate-Total';
+	public const PAGINATE_TOKEN_HEADER = 'X-NC-Paginate-Token';
+	public const PAGINATE_OFFSET_HEADER = 'X-NC-Paginate-Offset';
+	public const PAGINATE_COUNT_HEADER = 'X-NC-Paginate-Count';
+
+	/** @var Server */
+	private $server;
+
+	public function __construct(
+		private PaginateCache $cache,
+		private int $pageSize = 100,
+	) {
+	}
+
+	public function initialize(Server $server): void {
+		$this->server = $server;
+		$server->on('beforeMultiStatus', [$this, 'onMultiStatus']);
+		$server->on('method:SEARCH', [$this, 'onMethod'], 1);
+		$server->on('method:PROPFIND', [$this, 'onMethod'], 1);
+		$server->on('method:REPORT', [$this, 'onMethod'], 1);
+	}
+
+	public function getFeatures(): array {
+		return ['nc-paginate'];
+	}
+
+	public function onMultiStatus(&$fileProperties): void {
+		$request = $this->server->httpRequest;
+		if (is_array($fileProperties)) {
+			$fileProperties = new \ArrayIterator($fileProperties);
+		}
+		$url = $request->getUrl();
+		if (
+			$request->hasHeader(self::PAGINATE_HEADER) &&
+			(!$request->hasHeader(self::PAGINATE_TOKEN_HEADER) || !$this->cache->exists($url, $request->getHeader(self::PAGINATE_TOKEN_HEADER)))
+		) {
+			$pageSize = (int)$request->getHeader(self::PAGINATE_COUNT_HEADER) ?: $this->pageSize;
+			$offset = (int)$request->getHeader(self::PAGINATE_OFFSET_HEADER);
+			$copyIterator = new LimitedCopyIterator($fileProperties, $pageSize, $offset);
+			['token' => $token, 'count' => $count] = $this->cache->store($url, $copyIterator);
+
+			$fileProperties = $copyIterator->getRequestedItems();
+			$this->server->httpResponse->addHeader(self::PAGINATE_HEADER, 'true');
+			$this->server->httpResponse->addHeader(self::PAGINATE_TOKEN_HEADER, $token);
+			$this->server->httpResponse->addHeader(self::PAGINATE_TOTAL_HEADER, (string)$count);
+			$request->setHeader(self::PAGINATE_TOKEN_HEADER, $token);
+		}
+	}
+
+	public function onMethod(RequestInterface $request, ResponseInterface $response) {
+		$url = $this->server->httpRequest->getUrl();
+		if (
+			$request->hasHeader(self::PAGINATE_TOKEN_HEADER) &&
+			$request->hasHeader(self::PAGINATE_OFFSET_HEADER) &&
+			$this->cache->exists($url, $request->getHeader(self::PAGINATE_TOKEN_HEADER))
+		) {
+			$token = $request->getHeader(self::PAGINATE_TOKEN_HEADER);
+			$offset = (int)$request->getHeader(self::PAGINATE_OFFSET_HEADER);
+			$count = (int)$request->getHeader(self::PAGINATE_COUNT_HEADER) ?: $this->pageSize;
+
+			$items = $this->cache->get($url, $token, $offset, $count);
+
+			$response->setStatus(207);
+			$response->addHeader(self::PAGINATE_HEADER, 'true');
+			$response->setHeader('Content-Type', 'application/xml; charset=utf-8');
+			$response->setHeader('Vary', 'Brief,Prefer');
+
+			$prefer = $this->server->getHTTPPrefer();
+			$minimal = $prefer['return'] === 'minimal';
+
+			$data = $this->server->generateMultiStatus($items, $minimal);
+			$response->setBody($data);
+
+			return false;
+		}
+	}
+}