public function __construct($app, Filesystem $fs, Loader $loader)
{
$this->fs = $fs;
$this->app = $app;
$this->loader = $loader;
$this->files = array_values($loader->paths());
$this->parser = new JsonParser();
$this->schema_retriever = new \JsonSchema\Uri\UriRetriever();
$this->schema_resolver = new \JsonSchema\RefResolver($this->schema_retriever);
$this->schema_validator = new \JsonSchema\Validator();
}