XMLHttpRequest and Joomla global variables

Question

I have a system Joomla 3.x plugin with a restore its settings option. For this I use XMLHttpRequest to load a backup file. No problem this side. The problem is in the php file used to update the database. I cannot access the global variables of Joomla I know it's normal because the file isn't called from Joomla itself.

my script:

function uploadFile() {
var fd = new FormData();
fd.append("fileToUpload",  document.getElementById('fileToUpload').files[0]);
var xhr = new XMLHttpRequest();
xhr.upload.addEventListener("progress", uploadProgress, false);
xhr.addEventListener("load", uploadComplete, false);
xhr.addEventListener("error", uploadFailed, false);
xhr.addEventListener("abort", uploadCanceled, false);
xhr.open("POST", "restore.php");
xhr.send(fd);
}

restore.php file:

function import($_FILES)
{
if ($_FILES['fileToUpload']['error'] > 0) {
    echo "<p class='alert alert-error'>An error occurred while uploading!</p>";     
} else {
    $file_name = $_FILES['fileToUpload']['name'];
    $file_ext  = strtolower(end(explode(".", $file_name)));
    $file_size = $_FILES['fileToUpload']['size'];
    if (($file_ext == "json") && ($file_size < 500000)) {
        $options = file_get_contents($_FILES['fileToUpload']['tmp_name']);

        // Get a database object. 
        $db = JFactory::getDbo();

        // Create a new query object.
        $query = $db->getQuery(true);

        // Fields to update.
        $fields = array(
            $db->quoteName('field_to_update') . ' = ' . $db->quote($options)
        );

        // Conditions for which records should be updated.
        $conditions = array(
            $db->quoteName('element') . ' = ' . $db->quote('plugin_name'), 
            $db->quoteName('folder') . ' = ' . $db->quote('system')
        );

        // Set the query and execute it.
        $query->update($db->quoteName('#__extensions'))->set($fields)->where($conditions);
        $db->setQuery($query);
        $result = $db->execute();

        echo "<p class='alert alert-success'>Backup file successfully restored!</p>";
    } else {
        if ($file_ext <> "json") {
            echo "<p class='alert alert-error'>Invalid file type! Must be a JSON file.</p>";
        } elseif ($file_size > 500000) {
            echo "<p class='alert alert-error'>File too big!</p>";
        }
    }
}
return;
}

Is it possible to access the database global variables of Joomla in my called php file ?

Answer 1

You have to bootstrap a whole Joomla app to get CMS stack. Something along the line should work in your file:

define('_JEXEC', 1);

error_reporting(E_ALL | E_NOTICE);
ini_set('display_errors', 1);

define('JPATH_BASE', dirname(dirname(dirname(__FILE__))));
require_once JPATH_BASE . DS . 'includes' . DS . 'defines.php';
require_once JPATH_BASE . DS . 'includes' . DS . 'framework.php';

JLoader::import('joomla.user.authentication');
JLoader::import('joomla.application.component.helper');

class MyJoomlaServer extends JApplicationWeb {

    public function doExecute() {
        // Get a database object. 
        $db = JFactory::getDbo();

        // Create a new query object.
        $query = $db->getQuery(true);

        // Fields to update.
        $fields = array(
            $db->quoteName('field_to_update') . ' = ' . $db->quote($options)
        );

        ...
    }

    public function isAdmin() {
        return false;
    }
}

$app = JApplicationWeb::getInstance('MyJoomlaServer');
JFactory::$application = $app;
$app->execute();

Answer 2

Cannot execute a php file in administrator/component directory Cannot execute a php file in administrator/component directory

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