Airship\Cabin\Bridge\Blueprint\Files::isValidName PHP Method

    public function isValidName(string $name) : bool
    {
        if ($name === '.' || $name === '..') {
            // Web browsers will probably handle relative paths stupidly,
            // so let's avoid the hassle before it ever becomes one
            return false;
        }
        if (\strpos($name, '/') !== false || \strpos($name, '?') !== false || \strpos($name, '&') !== false) {
            // Once again, this is just looking to create a headache down the road.
            return false;
        }
        if (Util::stringLength($name) < 1) {
            return false;
        } elseif (Util::stringLength($name) === 1) {
            // Single byte directory/file names must be a printable ASCII character.
            // Preferably: one that is legible and semantically meaningful.
            return 0 < \preg_match('#^[A-Za-z0-9\\-_~=\\+]$#', $name[0]);
        }
        // No other rules yet.
        return true;
    }

 /**
  * Create a new directory for file uploads
  *
  * @param int $directoryId
  * @param string $cabin
  * @param array $post
  * @return array
  */
 protected function createDir($directoryId = null, string $cabin = '', array $post = []) : array
 {
     if (!\array_key_exists('directory', $post)) {
         return ['status' => 'ERROR', 'message' => 'Directory names cannot be empty'];
     }
     if (!$this->files->isValidName($post['directory'])) {
         return ['status' => 'ERROR', 'message' => 'Invalid directory name'];
     }
     if ($this->files->dirExists($directoryId, $cabin, $post['directory'])) {
         return ['status' => 'ERROR', 'message' => 'This directory already exists'];
     }
     if ($this->files->createDirectory($directoryId, $cabin, $post['directory'])) {
         return ['status' => 'SUCCESS', 'message' => 'This directory has been created sucessfully'];
     }
     return ['status' => 'UNKNOWN', 'message' => 'An unknown error has occurred.'];
 }