Sokil\Mongo\GridFS::getFileById PHP Метод

    public function getFileById($id)
    {
        if ($id instanceof \MongoId) {
            $file = $this->getMongoCollection()->findOne(array('_id' => $id));
        } else {
            try {
                $file = $this->getMongoCollection()->findOne(array('_id' => new \MongoId($id)));
            } catch (\MongoException $e) {
                $file = $this->getMongoCollection()->findOne(array('_id' => $id));
            }
        }
        if (!$file) {
            return null;
        }
        $fileClassName = $this->getFileClassName($file);
        return new $fileClassName($this, $file);
    }

 public function testGetResource()
 {
     $id = $this->gridFs->storeBytes('somebinarydata', array('meta' => 1));
     $this->assertTrue(is_resource($this->gridFs->getFileById($id)->getResource()));
 }