endpoints to fetch item's children

For /users/i:objectUserID/items/:objectKey/children and /groups/i:objectGroupID/items/:objectKey/children.
Only allows get requests.
Fixes: #113

Author: abaevbog

controllers/ApiController.php

@@ -55,6 +55,7 @@ class ApiController extends Controller {
 	protected $objectKey;
 	protected $objectName;
 	protected $subset;
+	protected $getOnly;
 	protected $singleObject;
 	protected $publications = false;
 	protected $legacyPublications = false;
@@ -446,6 +447,7 @@ public function init($extra) {
 
 		$this->scopeObject = !empty($extra['scopeObject']) ? $extra['scopeObject'] : $this->scopeObject;
 		$this->subset = !empty($extra['subset']) ? $extra['subset'] : $this->subset;
+		$this->getOnly = !empty($extra['getOnly']) ? $extra['getOnly'] : $this->getOnly;
 
 		$this->fileMode = !empty($extra['file'])
 							? (!empty($_GET['info']) ? 'info' : 'download')

controllers/ItemsController.php

@@ -425,6 +425,9 @@ public function items() {
 					);
 				}
 				else if ($this->subset == 'children') {
+					if ($this->getOnly) {
+						$this->allowMethods(array('GET'));
+					}
 					$item = Zotero_Items::getByLibraryAndKey($this->objectLibraryID, $this->objectKey);
 					if (!$item) {
 						$this->e404("Item not found");

include/config/routes.inc.php

@@ -34,6 +34,8 @@
 $router->map('/groups/i:objectGroupID/items/:objectKey/file', array('controller' => 'Items', 'extra' => array('allowHTTP' => true, 'file' => true)));
 $router->map('/groups/i:objectGroupID/items/:objectKey/file/view', array('controller' => 'Items', 'extra' => array('allowHTTP' => true, 'file' => true, 'view' => true)));
 $router->map('/groups/i:objectGroupID/items/:objectKey/file/view/url', ['controller' => 'Items', 'extra' => ['file' => true, 'viewurl' => true]]);
+$router->map('/users/i:objectUserID/items/:objectKey/children', ['controller' => 'Items', 'extra' => ['subset' => 'children', 'getOnly' => true]]);
+$router->map('/groups/i:objectGroupID/items/:objectKey/children', ['controller' => 'Items', 'extra' => ['subset' => 'children', 'getOnly' => true]]);
 
 // Full-text content
 $router->map('/users/i:objectUserID/items/:objectKey/fulltext', array('controller' => 'FullText', 'action' => 'itemContent'));