How to get user object in Ajax call

Question

I want to access the currently logged in user in my Helper function using AJAX.

function editUser(){
    runAjax('editUser',"one");
}
function runAjax(type,regHtml){
    request = {
        'option' : 'com_ajax',
        'module' : 'user_login',
        'cmd'    : type,
        'params' : params,
        'format' : 'json'
    };

    jQuery.ajax({
        type   : 'POST',
        data   : request,
        success: function (response) {

The editUser function is set off via a onmousedown button.

This all works fine and calls the helper function. The issue is on the helper side.

public static function getAjax()
{

    function setUpForm(){

        $user = JFactory::getUser();

        echo "<pre>";
        print_r($user);
        echo "</pre>";

    }


    $input = JFactory::getApplication()->input;
    $params  = $input->get('params',"",raw);

     $cmd  = $input->get('cmd');


    if($cmd == "editUser"){
        setUpForm();
    }

This works but isn't the recommended way of getting the user object. It's:

use Joomla\CMS\Factory;
$user = Factory::getUser();

This is the switch to use cases but this won't work with AJAX because the use won't work out of context I'd need to do something like:

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

to include extra files (I haven't tried it since it seems a mad way to go)

Is there a way around this.

Whilst I have working code I'm thinking about future proofing my code.

Update

I'm adding some cleaner code to show what doesn't work:

This doesn't work because it doesn't have the namespace context

class modLoginHelper

{

public static function getAjax()
    {
        use Joomla\CMS\Factory as YourNewAlias;
        user = Factory::getUser();
    }
    
}

This won't throw an error but doesn't work

class modLoginHelper

{
    use Joomla\CMS\Factory as YourNewAlias;
    
public static function getAjax()
    {
        
        user = Factory::getUser();
    }
    
}

So whichever way I try to follow the use Joomla ... it won't work - I have to revert to the old way of doing things.

Answer 1

When importing classes using use statement, it has to be outside of your class. When put inside a class, it's interpreted as a use of trait. And when used inside a method it will cause a syntax error. In your case it should be used like this:

use Joomla\CMS\Factory;

class ModLoginHelper
{ 
    public static function getAjax()
    {
        $user = Factory::getUser();
        // Your code here...
    }
}

From PHP documentation:

The use keyword must be declared in the outermost scope of a file (the global scope) or inside namespace declarations. This is because the importing is done at compile time and not runtime, so it cannot be block scoped.

https://www.php.net/manual/en/language.namespaces.importing.php

Alternatively, you can use fully qualified class names in your code like this:

class ModLoginHelper
{ 
    public static function getAjax()
    {
        $user = Joomla\CMS\Factory::getUser();
        // Your code here...
    }
}