Password Protect PDF in PHP SDK

    require_once 'vendor/autoload.php';

    use Aspose\PDF\Configuration;
    use Aspose\PDF\Model\CryptoAlgorithm;
    use Aspose\PDF\Api\PdfApi;

    $credentials = json_decode(file_get_contents(__DIR__ . "/../../../Credentials/credentials.json"), true);

    $configParams = [
        'LOCAL_FOLDER' => 'C:\\Samples\\',
        'PDF_DOCUMENT_NAME' => 'sample.pdf',
        'LOCAL_RESULT_DOCUMENT_NAME' => 'output_sample.pdf',
        'ENCRYPT_ALGORITHM' => CryptoAlgorithm::AE_SX256,
        'USER_PASSWORD' => 'User-Password',
        'OWNER_PASSWORD' => 'Owner-Password',
    ];

    class PdfEncoder {
        private $pdfApi;
        private $configParams;

        private function _create_rest_api() {
            $credentials = json_decode(file_get_contents("./Credentials/credentials.json"), true);

            $configAuth = new Configuration();
            $configAuth->setAppKey($credentials['key']);
            $configAuth->setAppSid($credentials['id']);

            $this->pdfApi = new PdfApi(null, $configAuth);
        }

        public function __construct($config) {
            $this->configParams = $config;
            $this->_create_rest_api();
        }

        public function uploadDocument() {
            $filePath = $this->configParams['LOCAL_FOLDER'] . $this->configParams['PDF_DOCUMENT_NAME'];
            $fileData = file_get_contents($filePath);

            $this->pdfApi->uploadFile($this->configParams['PDF_DOCUMENT_NAME'], $fileData);
            echo "File: '{$this->configParams['PDF_DOCUMENT_NAME']}' successfully uploaded.\n";
        }

        public function downloadResult() {
            $result = $this->pdfApi->downloadFile($this->configParams['PDF_DOCUMENT_NAME']);
            $outputPath = $this->configParams['LOCAL_FOLDER'] . $this->configParams['LOCAL_RESULT_DOCUMENT_NAME'];
            file_put_contents($outputPath, $result['body']);
            echo "Downloaded: {$outputPath}\n";
        }

        public function encryptDocument() {
            $userPassword = base64_encode($this->configParams['USER_PASSWORD']);
            $ownerPassword = base64_encode($this->configParams['OWNER_PASSWORD']);

            $response = $this->pdfApi->postEncryptDocumentInStorage(
                $this->configParams['PDF_DOCUMENT_NAME'],
                $userPassword,
                $ownerPassword,
                $this->configParams['ENCRYPT_ALGORITHM']
            );

            if ($response['body']['code'] == 200) {
                echo "encryptDocument(): Document '{$this->configParams['PDF_DOCUMENT_NAME']}' successfully encrypted.\n";
            } else {
                throw new Exception("encryptDocument(): Failed to encrypt document '{$this->configParams['PDF_DOCUMENT_NAME']}'. Response code: {$response['code']}");
            }
        }
    }

    function main() {
        global $configParams;

        $encoder = new PdfEncoder($configParams);

        try {
            $encoder->uploadDocument();
            $encoder->encryptDocument();
            $encoder->downloadResult();
        } catch (Exception $e) {
            echo "Error: " . $e->getMessage() . "\n";
        }
    }