1: <?php
 2: /**
 3:  * Magento
 4:  *
 5:  * NOTICE OF LICENSE
 6:  *
 7:  * This source file is subject to the Open Software License (OSL 3.0)
 8:  * that is bundled with this package in the file LICENSE.txt.
 9:  * It is also available through the world-wide-web at this URL:
10:  * http://opensource.org/licenses/osl-3.0.php
11:  * If you did not receive a copy of the license and are unable to
12:  * obtain it through the world-wide-web, please send an email
13:  * to license@magentocommerce.com so we can send you a copy immediately.
14:  *
15:  * DISCLAIMER
16:  *
17:  * Do not edit or add to this file if you wish to upgrade Magento to newer
18:  * versions in the future. If you wish to customize Magento for your
19:  * needs please refer to http://www.magentocommerce.com for more information.
20:  *
21:  * @category    Mage
22:  * @package     Mage_Core
23:  * @copyright   Copyright (c) 2012 Magento Inc. (http://www.magentocommerce.com)
24:  * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
25:  */
26: 
27: /**
28:  * Active record implementation
29:  *
30:  * @author      Magento Core Team <core@magentocommerce.com>
31:  */
32: class Mage_Core_Model_Resource_Iterator extends Varien_Object
33: {
34:     /**
35:      * Walk over records fetched from query one by one using callback function
36:      *
37:      * @param Zend_Db_Statement_Interface|Zend_Db_Select|string $query
38:      * @param array|string $callbacks
39:      * @param array $args
40:      * @param Varien_Db_Adapter_Interface $adapter
41:      * @return Mage_Core_Model_Resource_Iterator
42:      */
43:     public function walk($query, array $callbacks, array $args=array(), $adapter = null)
44:     {
45:         $stmt = $this->_getStatement($query, $adapter);
46:         $args['idx'] = 0;
47:         while ($row = $stmt->fetch()) {
48:             $args['row'] = $row;
49:             foreach ($callbacks as $callback) {
50:                 $result = call_user_func($callback, $args);
51:                 if (!empty($result)) {
52:                     $args = array_merge($args, $result);
53:                 }
54:             }
55:             $args['idx']++;
56:         }
57: 
58:         return $this;
59:     }
60: 
61:     /**
62:      * Fetch Zend statement instance
63:      *
64:      * @param Zend_Db_Statement_Interface|Zend_Db_Select|string $query
65:      * @param Zend_Db_Adapter_Abstract $conn
66:      * @return Zend_Db_Statement_Interface
67:      * @throws Mage_Core_Exception
68:      */
69:     protected function _getStatement($query, $conn = null)
70:     {
71:         if ($query instanceof Zend_Db_Statement_Interface) {
72:             return $query;
73:         }
74: 
75:         if ($query instanceof Zend_Db_Select) {
76:             return $query->query();
77:         }
78: 
79:         if (is_string($query)) {
80:             if (!$conn instanceof Zend_Db_Adapter_Abstract) {
81:                 Mage::throwException(Mage::helper('core')->__('Invalid connection'));
82:             }
83:             return $conn->query($query);
84:         }
85: 
86:         Mage::throwException(Mage::helper('core')->__('Invalid query'));
87:     }
88: }
89: