Agregar Páginas a PDF en PHP SDK

    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() {
        $fileNamePath = $this->configParams['LOCAL_FOLDER'] . $this->configParams['PDF_DOCUMENT_NAME'];
        $pdfFileData = file_get_contents($fileNamePath);
        $this->pdfApi->uploadFile($this->configParams['PDF_DOCUMENT_NAME'], $pdfFileData);
    }

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

    public function appendPage() {
        $resultPages = $this->pdfApi->putAddNewPage($this->configParams['PDF_DOCUMENT_NAME']);
        if ($resultPages->getCode() == 200) {
            $newPage = end($resultPages->getPages()->getList('list'));
            echo "Appended page:";
            var_dump($newPage);
        } else {
            echo "Unexpected error: can't get pages!!!\n";
        }
    }

    function main() {
        global $configParams;
        $pdfPages = new PdfPages($configParams);
        try {
            $pdfPages->uploadDocument();
            $pdfPages->appendPage();
            $pdfPages->downloadResult();
        } catch (Exception $e) {
            echo "Error: " . $e->getMessage() . "\n";
        }
    }