Getting file information in a directory using PHP

Question

I'm currently building a custom module in Drupal. I'm trying to get some file information (for example file name, date modified or uploaded, etc) and then display this information in a table.

The files are all PDF and are being uploaded via FTP.

Here are some links that I was using for reference:

Getting the names of all files in a directory with PHP

List all files in one directory PHP

I'm using the glob() and I double checked to see that my path is correct however I keep getting an empty array. Below is my code, I stripped out most of the information that's not necessary for this question. I have 3 different attempts in the code, but I'm not running all 3 together.

<?php 

namespace Drupal\Documents\Controller;

use Drupal\Core\Controller\ControllerBase;

class DocumentController extends ControllerBase  {

    public function documents(){

        global $base_url;

        $testPath = $base_url . '/sites/default/files/documents/';

        //Attempt One
        $newPath = $base_url . '/sites/default/files/documents/*.*';

        foreach(glob($newPath) as $file) {
            print_r($file);
            print_r('test');
        }

        //Attempt 2
        $log_directory = $base_url . '/sites/default/files/documents';

        print_r($log_directory);

        $results_array = array();

        if (is_dir($log_directory))
        {
                if ($handle = opendir($log_directory))
                {
                        //Notice the parentheses I added:
                        while(($file = readdir($handle)) !== FALSE)
                        {
                                $results_array[] = $file;
                                print_r('Testing');
                        }
                        closedir($handle);
                }
        }

        //Output findings
        foreach($results_array as $value)
        {
            echo $value . '<br />';
        } 

        //Attempt 3
        foreach (array_filter(glob($base_url . '/sites/default/files/documents/*'), 'is_file') as $file)
        {
            echo 'Test';
        }


    }
}

When I print_r() $testPath here is what I get, so path looks correct: http://localhost/drupaldev/sites/default/files/documents/