Add PatchPlugin

Signed-off-by: John Molakvoæ (skjnldsv) <skjnldsv@protonmail.com>

2 files changed, 210 insertions, 4 deletions

diff --git a/lib/AppInfo/Application.php b/lib/AppInfo/Application.php
index 565fe5b7..a2f3a396 100644
--- a/lib/AppInfo/Application.php
+++ b/lib/AppInfo/Application.php
@@ -22,16 +22,36 @@
  */
 namespace OCA\Contacts\AppInfo;
 
+use OCA\Contacts\Dav\PatchPlugin;
 use OCP\AppFramework\App;
+use OCP\EventDispatcher\IEventDispatcher;
+use OCP\SabrePluginEvent;
 
 class Application extends App {
 	public const APP_ID = 'contacts';
-
-	public function __construct() {
-		parent::__construct(self::APP_ID);
-	}
 	
 	public const AVAIL_SETTINGS = [
 		'allowSocialSync' => 'yes',
 	];
+
+	public function __construct() {
+		parent::__construct(self::APP_ID);
+	}
+
+	public function register() {
+		$server = $this->getContainer()->getServer();
+
+		/** @var IEventDispatcher $eventDispatcher */
+		$eventDispatcher = $server->query(IEventDispatcher::class);
+		$eventDispatcher->addListener('OCA\DAV\Connector\Sabre::addPlugin', function (SabrePluginEvent $event) {
+			$server = $event->getServer();
+
+			if ($server !== null) {
+				// We have to register the LockPlugin here and not info.xml,
+				// because info.xml plugins are loaded, after the
+				// beforeMethod:* hook has already been emitted.
+				$server->addPlugin($this->getContainer()->query(PatchPlugin::class));
+			}
+		});
+	}
 }
diff --git a/lib/Dav/PatchPlugin.php b/lib/Dav/PatchPlugin.php
new file mode 100644
index 00000000..61f36b7a
--- /dev/null
+++ b/lib/Dav/PatchPlugin.php
@@ -0,0 +1,186 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2020 John Molakvoæ <skjnldsv@protonmail.com>
+ *
+ * @author John Molakvoæ (skjnldsv) <skjnldsv@protonmail.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Contacts\Dav;
+
+use Sabre\CardDAV\Card;
+use Sabre\DAV;
+use Sabre\DAV\INode;
+use Sabre\DAV\PropPatch;
+use Sabre\DAV\Server;
+use Sabre\DAV\ServerPlugin;
+use Sabre\HTTP\RequestInterface;
+use Sabre\HTTP\ResponseInterface;
+use Sabre\VObject\Component\VCard;
+use Sabre\VObject\Reader;
+
+class PatchPlugin extends ServerPlugin {
+	public const METHOD_REPLACE = 0;
+	public const METHOD_APPEND = 1;
+
+	/** @var Server */
+	protected $server;
+
+	/**
+	 * Initializes the plugin and registers event handlers
+	 *
+	 * @param Server $server
+	 * @return void
+	 */
+	public function initialize(Server $server) {
+		$this->server = $server;
+		$server->on('method:PATCH', [$this, 'httpPatch']);
+	}
+
+	/**
+	 * Use this method to tell the server this plugin defines additional
+	 * HTTP methods.
+	 *
+	 * This method is passed a uri. It should only return HTTP methods that are
+	 * available for the specified uri.
+	 *
+	 * We claim to support PATCH method (partirl update) if and only if
+	 *     - the node exist
+	 *     - the node implements our partial update interface
+	 *
+	 * @param string $uri
+	 *
+	 * @return array
+	 */
+	public function getHTTPMethods($uri) {
+		$tree = $this->server->tree;
+
+		if ($tree->nodeExists($uri)) {
+			$node = $tree->getNodeForPath($uri);
+			if ($node instanceof Card) {
+				return ['PATCH'];
+			}
+		}
+
+		return [];
+	}
+
+	/**
+	 * Adds all CardDAV-specific properties
+	 *
+	 * @param PropPatch $propPatch
+	 * @param INode $node
+	 * @return void
+	 */
+	public function httpPatch(RequestInterface $request, ResponseInterface $response) {
+		$path = $request->getPath();
+		$node = $this->server->tree->getNodeForPath($path);
+
+		if (!($node instanceof Card)) {
+			return true;
+		}
+
+		// Checking ACL, if available.
+		if ($aclPlugin = $this->server->getPlugin('acl')) {
+			/** @var \Sabre\DAVACL\Plugin $aclPlugin */
+			$aclPlugin->checkPrivileges($path, '{DAV:}write');
+		}
+
+		// Init property name & value
+		$propertyName = $request->getHeader('X-Property');
+		if (is_null($propertyName)) {
+			throw new DAV\Exception\BadRequest('No valid "X-Property" found in the headers');
+		}
+
+		$propertyData = $request->getHeader('X-Property-Replace');
+		$method = self::METHOD_REPLACE;
+		if (is_null($propertyData)) {
+			$propertyData = $request->getHeader('X-Property-Append');
+			$method = self::METHOD_APPEND;
+			if (is_null($propertyData)) {
+				throw new DAV\Exception\BadRequest('No valid "X-Property-Append" or "X-Property-Replace" found in the headers');
+			}
+		}
+
+		// Init contact
+		$vCard = Reader::read($node->get());
+		$properties = $vCard->select($propertyName);
+
+		// We cannot know which one to update in that case
+		if (count($properties) > 1) {
+			throw new DAV\Exception\BadRequest('The specified property appear more than once');
+		}
+		
+		// Init if not in the vcard
+		if (count($properties) === 0) {
+			$vCard->add($propertyName, $propertyData);
+			$properties = $vCard->select($propertyName);
+		}
+
+		// Replace existing value
+		if ($method === self::METHOD_REPLACE) {
+			$properties[0]->setRawMimeDirValue($propertyData);
+		}
+
+		// Append to existing value
+		if ($method === self::METHOD_APPEND) {
+			$oldData = $properties[0]->getValue();
+			$properties[0]->setRawMimeDirValue($oldData.$propertyData);
+		}
+	
+		// Validate & write
+		$vCard->validate();
+		$node->put($vCard->serialize());
+		$response->setStatus(200);
+
+		return false;
+	}
+
+	/**
+	 * Returns a plugin name.
+	 *
+	 * Using this name other plugins will be able to access other plugins
+	 * using \Sabre\DAV\Server::getPlugin
+	 *
+	 * @return string
+	 */
+	public function getPluginName() {
+		return 'vcard-patch';
+	}
+
+	/**
+	 * Returns a bunch of meta-data about the plugin.
+	 *
+	 * Providing this information is optional, and is mainly displayed by the
+	 * Browser plugin.
+	 *
+	 * The description key in the returned array may contain html and will not
+	 * be sanitized.
+	 *
+	 * @return array
+	 */
+	public function getPluginInfo() {
+		return [
+			'name'        => $this->getPluginName(),
+			'description' => 'Allow to patch unique properties.'
+		];
+	}
+}