Obtener formularios PDF con SDK PHP

<?php
require_once 'vendor/autoload.php';

use Aspose\PDF\Api\PdfApi;

function getFormFields() {
    $LOCAL_FILE_NAME = "C:\\Samples\\sample.pdf";
    $STORAGE_FILE_NAME = "sample.pdf";
    
    // Load credentials from JSON file
    $credentials = json_decode(file_get_contents('credentials.json'), true);
    
    $pdfApi = new PdfApi($credentials['id'], $credentials['key']);
    
    try {
        // Load Pdf file
        $fileData = file_get_contents($LOCAL_FILE_NAME);
        $uploadResult = $pdfApi->uploadFile($STORAGE_FILE_NAME, $fileData);
        echo $uploadResult->getResponseText() . PHP_EOL;
    } catch (Exception $e) {
        echo 'Error uploading file: ' . $e->getMessage() . PHP_EOL;
    }
    
    try {
        // Extract PDF form fileds
        $response = $pdfApi->getFields($STORAGE_FILE_NAME,);
        
        if ($response && $response->getFields() && $response->getFields()->getList()) {
            foreach ($response->getFields()->getList() as $item) {
                if ($item->getType() == "List") {
                    $values = implode(', ', $item->getValues());
                    echo "Name: [{$item->getName()}] Value: [{$values}]" . PHP_EOL;
                } else {
                    $value = $item->getValues()[0] ?? '';
                    echo "Name: [{$item->getName()}] Value: [{$value}]" . PHP_EOL;
                }
            }
        }
    } catch (Exception $error) {
        echo "Error processing PDF: " . $error->getMessage() . PHP_EOL;
    }
}

getFormFields();