public function registerFileStreamWrapper($force = false) { if ($force || !$this->fileStreamWrapperRegistered) { /* @var $class \yii\mongodb\file\StreamWrapper */ $class = $this->fileStreamWrapperClass; $class::register($this->fileStreamProtocol, $force); $this->fileStreamWrapperRegistered = true; } return $this->fileStreamProtocol; }