Fix functions to search for principals in the backend.

Add a "searchPrincipals" function to the NC principal backend.
Fix the "findByUri" function to respect the prefixPath.

Signed-off-by: Christoph Seitz <christoph.seitz@posteo.de>

apps/dav/lib/CalDAV/Principal/Collection.php

@@ -0,0 +1,45 @@
+<?php
+
+/**
+ * @copyright Copyright (c) 2017, Christoph Seitz <christoph.seitz@posteo.de>
+ *
+ * @author Christoph Seitz <christoph.seitz@posteo.de>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Principal;
+
+use OCA\DAV\CalDAV\Principal\User;
+
+/**
+ * Class Collection
+ *
+ * @package OCA\DAV\CalDAV\Principal
+ */
+class Collection extends \Sabre\CalDAV\Principal\Collection {
+
+	/**
+	 * Returns a child object based on principal information
+	 *
+	 * @param array $principalInfo
+	 * @return User
+	 */
+	function getChildForPrincipal(array $principalInfo) {
+		return new User($this->principalBackend, $principalInfo);
+	}
+
+}

apps/dav/lib/CalDAV/Principal/User.php

@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * @copyright Copyright (c) 2017, Christoph Seitz <christoph.seitz@posteo.de>
+ *
+ * @author Christoph Seitz <christoph.seitz@posteo.de>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\DAV\CalDAV\Principal;
+
+/**
+ * Class User
+ *
+ * @package OCA\DAV\CalDAV\Principal
+ */
+class User extends \Sabre\CalDAV\Principal\User {
+
+	/**
+	 * Returns a list of ACE's for this node.
+	 *
+	 * Each ACE has the following properties:
+	 *   * 'privilege', a string such as {DAV:}read or {DAV:}write. These are
+	 *     currently the only supported privileges
+	 *   * 'principal', a url to the principal who owns the node
+	 *   * 'protected' (optional), indicating that this ACE is not allowed to
+	 *      be updated.
+	 *
+	 * @return array
+	 */
+	function getACL() {
+		$acl = parent::getACL();
+		$acl[] = [
+			'privilege' => '{DAV:}read',
+			'principal' => '{DAV:}authenticated',
+			'protected' => true,
+		];
+		return $acl;
+	}
+
+}

apps/dav/lib/Connector/Sabre/Principal.php

@@ -182,6 +182,46 @@ class Principal implements BackendInterface {
 		return 0;
 	}
 
+	/**
+	 * Search user principals
+	 *
+	 * @param array $searchProperties
+	 * @param string $test
+	 * @return array
+	 */
+	function searchUserPrincipals(array $searchProperties, $test = 'allof') {
+		$results = [];
+
+		//TODO: If more properties should be supported, hook this up to a db query
+		foreach ($searchProperties as $prop => $value) {
+			switch ($prop) {
+				case '{http://sabredav.org/ns}email-address':
+					$users = $this->userManager->getByEmail($value);
+					$results[] =  array_map(function ($user) {
+						return $this->principalPrefix . '/' . $user->getUID();
+					}, $users);
+					break;
+				default:
+					$results[] = [];
+					break;
+			}
+		}
+
+		if (count($results) == 1) {
+			return $results[0];
+		}
+
+		switch ($test) {
+			case 'allof':
+
+				return array_intersect(...$results);
+			case 'anyof':
+				return array_unique(array_merge(...$results));
+		}
+
+		return [];
+	}
+
 	/**
 	 * @param string $prefixPath
 	 * @param array $searchProperties
@@ -189,7 +229,16 @@ class Principal implements BackendInterface {
 	 * @return array
 	 */
 	function searchPrincipals($prefixPath, array $searchProperties, $test = 'allof') {
-		return [];
+		if (count($searchProperties) == 0) {
+			return [];
+		}
+
+		switch ($prefixPath) {
+			case 'principals/users':
+				return $this->searchUserPrincipals($searchProperties, $test);
+			default:
+				return [];
+		}
 	}
 
 	/**
@@ -199,10 +248,12 @@ class Principal implements BackendInterface {
 	 */
 	function findByUri($uri, $principalPrefix) {
 		if (substr($uri, 0, 7) === 'mailto:') {
-			$email = substr($uri, 7);
-			$users = $this->userManager->getByEmail($email);
-			if (count($users) === 1) {
-				return $this->principalPrefix . '/' . $users[0]->getUID();
+			if ($principalPrefix === principals/users) {
+				$email = substr($uri, 7);
+				$users = $this->userManager->getByEmail($email);
+				if (count($users) === 1) {
+					return $this->principalPrefix . '/' . $users[0]->getUID();
+				}
 			}
 		}
 

apps/dav/lib/RootCollection.php

@@ -32,7 +32,7 @@ use OCA\DAV\CardDAV\CardDavBackend;
 use OCA\DAV\Connector\Sabre\Principal;
 use OCA\DAV\DAV\GroupPrincipalBackend;
 use OCA\DAV\DAV\SystemPrincipalBackend;
-use Sabre\CalDAV\Principal\Collection;
+use OCA\DAV\CalDAV\Principal\Collection;
 use Sabre\DAV\SimpleCollection;
 
 class RootCollection extends SimpleCollection {