From 5d8f769b0fda90fb5f8de2327da317b915075922 Mon Sep 17 00:00:00 2001
From: Tamino Bauknecht <dev@tb6.eu>
Date: Wed, 15 Nov 2023 21:35:09 +0100
Subject: [PATCH] Initial draft for PROPFIND for symlinks

---
 apps/dav/lib/Connector/Sabre/FilesPlugin.php | 71 ++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/apps/dav/lib/Connector/Sabre/FilesPlugin.php b/apps/dav/lib/Connector/Sabre/FilesPlugin.php
index ad77f58d16845..dea6ccbee8b94 100644
--- a/apps/dav/lib/Connector/Sabre/FilesPlugin.php
+++ b/apps/dav/lib/Connector/Sabre/FilesPlugin.php
@@ -169,6 +169,7 @@ public function initialize(Server $server) {
 		$this->server->on('afterBind', [$this, 'sendFileIdHeader']);
 		$this->server->on('afterWriteContent', [$this, 'sendFileIdHeader']);
 		$this->server->on('method:GET', [$this,'httpGet']);
+        $this->server->on('method:PROPFIND', [$this, 'httpPropFind']);
 		$this->server->on('afterMethod:GET', [$this,'afterHttpGet']);
 		$this->server->on('afterMethod:GET', [$this, 'handleDownloadToken']);
 		$this->server->on('afterResponse', function ($request, ResponseInterface $response) {
@@ -234,6 +235,76 @@ public function handleDownloadToken(RequestInterface $request, ResponseInterface
 		}
 	}
 
+	/**
+	 * Handle PROPFIND http requests for symlinks
+	 * @param RequestInterface $request
+	 * @param ResponseInterface $response
+	 */
+	public function httpPropFind(RequestInterface $request, ResponseInterface $response)
+	{
+		// only handle symlinks
+		// TODO: probably doesn't work because PROPFIND will be called on root dir and children are returned
+		$symlinkPath = $request->getPath();
+		$fileInfo = \OC\Files\Filesystem::getView()->getFileInfo($symlinkPath);
+		if (!$fileInfo || $fileInfo->getType() !== \OC\Files\FileInfo::TYPE_SYMLINK) {
+			return;
+		}
+
+		$requestBody = $request->getBodyAsString();
+		if (strlen($requestBody)) {
+			try {
+				$propFindXml = $this->server->xml->expect('{DAV:}propfind', $requestBody);
+			} catch (\Sabre\XML\ParseException $e) {
+				throw new \Sabre\DAV\Exception\BadRequest($e->getMessage(), 0, $e);
+			}
+		} else {
+			$propFindXml = new \Sabre\DAV\Xml\Request\PropFind();
+			$propFindXml->allProp = true;
+			$propFindXml->properties = [];
+		}
+
+		$newProperties = [];
+		foreach ($propFindXml->properties as $property) {
+			if ($property === self::GETETAG_PROPERTYNAME) {
+				$newProperties[$property] = [200, $fileInfo->getETag()];
+			} elseif ($property === self::LASTMODIFIED_PROPERTYNAME) {
+				// TODO
+			} elseif ($property === self::CREATIONDATE_PROPERTYNAME) {
+				// TODO
+			} elseif ($property === self::UPLOAD_TIME_PROPERTYNAME) {
+				// TODO
+			} elseif ($property === self::SIZE_PROPERTYNAME) {
+				$newProperties[$property] = [200, $fileInfo->getSize()];
+			} else { // TODO: handle other properties that make sense for symlinks
+				$newProperties[$property] = [404];
+			}
+		}
+
+		// This is a multi-status response
+		$response->setStatus(207);
+		$response->setHeader('Content-Type', 'application/xml; charset=utf-8');
+		$response->setHeader('Vary', 'Brief,Prefer');
+
+		// Normally this header is only needed for OPTIONS responses, however..
+		// iCal seems to also depend on these being set for PROPFIND. Since
+		// this is not harmful, we'll add it.
+		$features = ['1', '3', 'extended-mkcol'];
+		foreach ($this->server->getPlugins() as $plugin) {
+			$features = array_merge($features, $plugin->getFeatures());
+		}
+		$response->setHeader('DAV', implode(', ', $features));
+
+		$prefer = $this->server->getHTTPPrefer();
+		$minimal = 'minimal' === $prefer['return'];
+
+		$data = $this->server->generateMultiStatus($newProperties, $minimal);
+		$response->setBody($data);
+
+		// Sending back false will interrupt the event chain and tell the server
+		// we've handled this method.
+		return false;
+    }
+
 	public function httpGet(RequestInterface $request, ResponseInterface $response) {
 		// only handle symlinks
 		$symlinkPath = $request->getPath();