Tiny slim json view.

SlimJsonView.php

class SlimJsonView extends \Slim\View
{
    public function render($template = null)
    {
        $app = \Slim\Slim::getInstance();

        !$this->has('error') && $this->data->remove('flash');
        !$this->has('flash') && $this->data->remove('flash');

        $app->response()->header('Content-Type', 'application/json');
        $app->response()->body(json_encode($this->all()));
    }
}