$vst_hostname = 'dfsdfl.csfdsdsgds.com';

$postvars = array(
$vst_username = 'zdeslogin',
$vst_password = 'zdesparol',
$vst_returncode = 'yes',
$vst_command = 'v-add-user',
$username = 'demo',
$password = 'd3m0p4ssw0rd',
$email = 'demo@gmail.com',
$package = 'default',
$fist_name = 'Rust',
$last_name = 'Cohle'
);

$postdata = http_build_query($postvars);

$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, 'https://' . $vst_hostname . ':8083/api/');
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, false);
curl_setopt($curl, CURLOPT_POST, true);
curl_setopt($curl, CURLOPT_POSTFIELDS, $postdata);
$answer = curl_exec($curl);
// Check result
if($answer == 0) {
    echo "User account has been successfuly createdn";
} else {
    echo "Query returned error code: " .$answer. "n";
}