send share notification instead of erroring on duplicate share

when creating a share that already exists, instead of erroring, resend the notifications

Signed-off-by: Robin Appelman <robin@icewind.nl>

lib/composer/composer/autoload_classmap.php

@@ -489,6 +489,7 @@ return array(
     'OCP\\Share\\Events\\ShareCreatedEvent' => $baseDir . '/lib/public/Share/Events/ShareCreatedEvent.php',
     'OCP\\Share\\Events\\ShareDeletedEvent' => $baseDir . '/lib/public/Share/Events/ShareDeletedEvent.php',
     'OCP\\Share\\Events\\VerifyMountPointEvent' => $baseDir . '/lib/public/Share/Events/VerifyMountPointEvent.php',
+    'OCP\\Share\\Exceptions\\AlreadySharedException' => $baseDir . '/lib/public/Share/Exceptions/AlreadySharedException.php',
     'OCP\\Share\\Exceptions\\GenericShareException' => $baseDir . '/lib/public/Share/Exceptions/GenericShareException.php',
     'OCP\\Share\\Exceptions\\IllegalIDChangeException' => $baseDir . '/lib/public/Share/Exceptions/IllegalIDChangeException.php',
     'OCP\\Share\\Exceptions\\ShareNotFound' => $baseDir . '/lib/public/Share/Exceptions/ShareNotFound.php',

lib/composer/composer/autoload_static.php

@@ -518,6 +518,7 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OCP\\Share\\Events\\ShareCreatedEvent' => __DIR__ . '/../../..' . '/lib/public/Share/Events/ShareCreatedEvent.php',
         'OCP\\Share\\Events\\ShareDeletedEvent' => __DIR__ . '/../../..' . '/lib/public/Share/Events/ShareDeletedEvent.php',
         'OCP\\Share\\Events\\VerifyMountPointEvent' => __DIR__ . '/../../..' . '/lib/public/Share/Events/VerifyMountPointEvent.php',
+        'OCP\\Share\\Exceptions\\AlreadySharedException' => __DIR__ . '/../../..' . '/lib/public/Share/Exceptions/AlreadySharedException.php',
         'OCP\\Share\\Exceptions\\GenericShareException' => __DIR__ . '/../../..' . '/lib/public/Share/Exceptions/GenericShareException.php',
         'OCP\\Share\\Exceptions\\IllegalIDChangeException' => __DIR__ . '/../../..' . '/lib/public/Share/Exceptions/IllegalIDChangeException.php',
         'OCP\\Share\\Exceptions\\ShareNotFound' => __DIR__ . '/../../..' . '/lib/public/Share/Exceptions/ShareNotFound.php',

lib/private/Share20/Manager.php

@@ -63,6 +63,7 @@ use OCP\Security\Events\ValidatePasswordPolicyEvent;
 use OCP\Security\IHasher;
 use OCP\Security\ISecureRandom;
 use OCP\Share;
+use OCP\Share\Exceptions\AlreadySharedException;
 use OCP\Share\Exceptions\GenericShareException;
 use OCP\Share\Exceptions\ShareNotFound;
 use OCP\Share\IManager;
@@ -566,7 +567,7 @@ class Manager implements IManager {
 
 			// Identical share already existst
 			if ($existingShare->getSharedWith() === $share->getSharedWith() && $existingShare->getShareType() === $share->getShareType()) {
-				throw new \Exception('Path is already shared with this user');
+				throw new AlreadySharedException('Path is already shared with this user', $existingShare);
 			}
 
 			// The share is already shared with this user via a group share
@@ -576,7 +577,7 @@ class Manager implements IManager {
 					$user = $this->userManager->get($share->getSharedWith());
 
 					if ($group->inGroup($user) && $existingShare->getShareOwner() !== $share->getShareOwner()) {
-						throw new \Exception('Path is already shared with this user');
+						throw new AlreadySharedException('Path is already shared with this user', $existingShare);
 					}
 				}
 			}
@@ -621,7 +622,7 @@ class Manager implements IManager {
 			}
 
 			if ($existingShare->getSharedWith() === $share->getSharedWith() && $existingShare->getShareType() === $share->getShareType()) {
-				throw new \Exception('Path is already shared with this group');
+				throw new AlreadySharedException('Path is already shared with this group', $existingShare);
 			}
 		}
 	}
@@ -735,6 +736,7 @@ class Manager implements IManager {
 			}
 		}
 
+		try {
 			//Verify share type
 			if ($share->getShareType() === IShare::TYPE_USER) {
 				$this->userCreateChecks($share);
@@ -786,7 +788,7 @@ class Manager implements IManager {
 			}
 
 			// Generate the target
-		$target = $this->config->getSystemValue('share_folder', '/') .'/'. $share->getNode()->getName();
+			$target = $this->config->getSystemValue('share_folder', '/') . '/' . $share->getNode()->getName();
 			$target = \OC\Files\Filesystem::normalizePath($target);
 			$share->setTarget($target);
 
@@ -807,6 +809,10 @@ class Manager implements IManager {
 			if ($share->getTarget() === '') {
 				$share->setTarget($target);
 			}
+		} catch (AlreadySharedException $e) {
+			// if a share for the same target already exists, dont create a new one, but do trigger the hooks and notifications again
+			$share = $e->getExistingShare();
+		}
 
 		// Post share event
 		$event = new GenericEvent($share);

lib/public/Share/Exceptions/AlreadySharedException.php

@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Robin Appelman <robin@icewind.nl>
+ *
+ * @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 OCP\Share\Exceptions;
+
+use OCP\Share\IShare;
+
+/**
+ * @since 22.0.0
+ */
+class AlreadySharedException extends GenericShareException {
+	/** @var IShare */
+	private $existingShare;
+
+	/**
+	 * @since 22.0.0
+	 */
+	public function __construct(string $message, IShare $existingShare) {
+		parent::__construct($message);
+
+		$this->existingShare = $existingShare;
+	}
+
+	/**
+	 * @since 22.0.0
+	 */
+	public function getExistingShare(): IShare {
+		return $this->existingShare;
+	}
+}