a Tiga (WP plugin) controller to handle notifications sent by veritrans

VeritransController.php

<?php
class VeritransController {

	public function index() {
		global $woocommerce;
		// get veritrans keys depending on environment (sandbox/production)
		$vt = get_option('woocommerce_veritrans_settings');
		if (empty($vt)) {
			return Response::json(array("success"=>false,"error"=>"veritrans setting not found"),200,array());;
		}
		if ($vt['select_veritrans_environment'] == 'production') {
			$serverkey = $vt['server_key_v2_production'];
		} else if ($vt['select_veritrans_environment'] == 'sandbox') {
			$serverkey = $vt['server_key_v2_sandbox'];
		} else {
			return Response::json(array("success"=>false,"error"=>"veritrans environment not set"),200,array());;
		}

		// parameters check
		if (!Request::has('order_id') || !Request::has('status_code') || !Request::has('gross_amount') || !Request::has('signature_key')) {
			return Response::json(array("success"=>false,"error"=>"invalid parameters"),200,array());;
		}

		$req = Request::all();

		$order_id 			= (int)$req["order_id"];
		$order_status 		= $req["status_code"];
		$order_date 		= $req["transaction_time"];
		$order_amount		= $req["gross_amount"];
		$signature_key		= $req["signature_key"];

		//generate signature key
		$generated_signature = openssl_digest($order_id.$order_status.$order_amount.$serverkey, 'sha512');
		if ($generated_signature != $signature_key) {
			return Response::json(array("success"=>false,"error"=>"signature key not valid"),200,array());;
		}

		$order 				= new WC_Order($order_id);
		$user_id			= $order->get_user_id();

		if ($order_status == "200") { //if payment success
			$order->update_status( 'completed' );
		}

		return Response::json(array(
			"success"=>true,
			"order_id"=> $order_id,
			"user_id"=> $user_id
		),200,array());
	}

}