curl_setopt($handle, CURLOPT_POST, true);
curl_setopt($handle, CURLOPT_HTTPHEADER , ['Content-Type: multipart/form-data']);
curl_setopt($curl, CURLOPT_POSTFIELDS, ['file' => base64_encode($file_content)]);
// https://www.php.net/manual/en/class.streamwrapper.php
stream_wrapper_register('fakefile', 'FakeFileStreamWrapper');