feature(actions): adds a generic delete action

Plugins can now use action/delete?guid=$guid to delete an entity.
The action file provides for an easy way to define custom translation keys,
as well as a forward URL.

Refs #5922

actions/entities/delete.php

@@ -6,17 +6,6 @@
  * @subpackage Core
  */
 
-$guid = get_input('guid');
-$entity = get_entity($guid);
+elgg_deprecated_notice('entities/delete action file has been deprecated. Use entity/delete action instead', '2.1');
 
-if (($entity) && ($entity->canEdit())) {
-	if ($entity->delete()) {
-		system_message(elgg_echo('entity:delete:success', array($guid)));
-	} else {
-		register_error(elgg_echo('entity:delete:fail', array($guid)));
-	}
-} else {
-	register_error(elgg_echo('entity:delete:fail', array($guid)));
-}
-
-forward(REFERER);
+return require dirname(dirname(__FILE__)) . '/entity/delete.php';

actions/entity/delete.php

@@ -0,0 +1,66 @@
+<?php
+
+/**
+ * Default entity delete action
+ */
+$guid = get_input('guid');
+$entity = get_entity($guid);
+
+if (!$entity instanceof ElggEntity) {
+	register_error(elgg_echo('entity:delete:item_not_found'));
+	forward(REFERRER);
+}
+
+if (!$entity->canDelete()) {
+	register_error(elgg_echo('entity:delete:permission_denied'));
+	forward(REFERRER);
+}
+
+set_time_limit(0);
+
+// determine what name to show on success
+$display_name = $entity->getDisplayName();
+if (!$display_name) {
+	$display_name = elgg_echo('entity:delete:item');
+}
+
+$type = $entity->getType();
+$subtype = $entity->getSubtype();
+$container = $entity->getContainerEntity();
+
+if (!$entity->delete()) {
+	register_error(elgg_echo('entity:delete:fail', array($display_name)));
+	forward(REFERRER);
+}
+
+// determine forward URL
+$forward_url = get_input('forward_url');
+if (!$forward_url) {
+	$forward_url = REFERRER;
+	$referrer_url = !empty($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '';
+	$site_url = elgg_get_site_url();
+	if ($referrer_url && 0 == strpos($referrer_url, $site_url)) {
+		$referrer_path = substr($referrer_url, 0, strlen($site_url));
+		$segments = explode('/', $referrer_path);
+		if (in_array($guid, $segments)) {
+			// referrer URL contains a reference to the entity that will be deleted
+			$forward_url = ($container) ? $container->getURL() : '';
+		}
+	} else if ($container) {
+		$forward_url = $container->getURL() ? : '';
+	}
+}
+
+$success_keys = array(
+	"entity:delete:$type:$subtype:success",
+	"entity:delete:$type:success",
+	"entity:delete:success",
+);
+
+foreach ($success_keys as $success_key) {
+	if (elgg_language_key_exists($success_key)) {
+		system_message(elgg_echo($success_key, array($display_name)));
+		break;
+	}
+}
+forward($forward_url);

docs/guides/actions.rst

@@ -137,6 +137,38 @@ This is done as follows:
 This lets a plugin extend an existing action without the need to replace the whole action. In the case of the captcha plugin it allows the plugin to provide captcha support in a very loosely coupled way.
 
 
+Actions available in core
+=========================
+
+``entity/delete``
+-------------------
+
+If your plugin does not implement any custom logic when deleting an entity, you can use bundled delete action
+
+.. code-block:: php
+
+   $guid = 123;
+   // You can provide optional forward path as a URL query parameter
+   $forward_url = 'path/to/forward/to';
+   echo elgg_view('output/url', array(
+      'text' => elgg_echo('delete'),
+      'href' => "action/entity/delete?guid=$guid&forward_url=$forward_url",
+      'confirm' => true,
+   ));
+
+
+You can customize the success message keys for your entity type and subtype, using ``"entity:delete:$type:$subtype:success"`` and ``"entity:delete:$type:success"`` keys.
+
+.. code-block:: php
+
+   // to add a custom message when a blog post or file is deleted
+   // add the translations keys in your language files
+   return array(
+      'entity:delete:object:blog:success' => 'Blog post has been deleted,
+      'entity:delete:object:file:success' => 'File titled %s has been deleted',
+   );
+
+
 Forms
 =====
 

engine/lib/elgglib.php

@@ -1924,6 +1924,8 @@ function _elgg_engine_boot() {
 function _elgg_init() {
 	global $CONFIG;
 
+	elgg_register_action('entity/delete');
+
 	elgg_register_action('comment/save');
 	elgg_register_action('comment/delete');
 

languages/en.php

@@ -1287,8 +1287,11 @@
 	'entity:default:strapline' => 'Created %s by %s',
 	'entity:default:missingsupport:popup' => 'This entity cannot be displayed correctly. This may be because it requires support provided by a plugin that is no longer installed.',
 
-	'entity:delete:success' => 'Entity %s has been deleted',
-	'entity:delete:fail' => 'Entity %s could not be deleted',
+	'entity:delete:item' => 'Item',
+	'entity:delete:item_not_found' => 'Item not found.',
+	'entity:delete:permission_denied' => 'You do not have permissions to delete this item.',
+	'entity:delete:success' => '%s has been deleted.',
+	'entity:delete:fail' => '%s could not be deleted.',
 
 	'entity:can_delete:invaliduser' => 'Cannot check canDelete() for user_guid [%s] as the user does not exist.',