class DataSet implements DataSetInterface
{
    private $object;

    private function __construct($object)
    {
        $this->object = $object;
    }

    public static function fromObject($object)
    {
        return new self($object);
    }

    public function getAttributeValue(string $attribute)
    {
        if (!$this->hasAttribute($attribute)) {
            throw new MissingAttributeException('$attribute is missing');
        }

        return get_object_vars($this->object)[$attribute];
    }

    public function hasAttribute(string $attribute): bool
    {
        return array_key_exists($attribute, get_object_vars($this->object));
    }
}

class Post
{
    public string $title;
    public string $description;
}

$dataSet = DataSet::fromObject(new Post());