public function generate(Request $request)
    {
        if (count($request->getArgs()) != 1) {
            echo 'Wrong arguments.' . PHP_EOL . 'Usage : db/generate mapping_name' . PHP_EOL;
        } else {
            $mapping = $request->getArgs()[0];
            $schema = Schema::getSchema($mapping);
            $schema->generateModels();
        }
    }