Imbo\EventListener\Cors::invoke PHP Method

    public function invoke(EventInterface $event)
    {
        $request = $event->getRequest();
        $resource = (string) $request->getRoute();
        $method = $request->getMethod();
        $allowed = $this->params['allowedMethods'];
        if (!isset($allowed[$resource]) || !in_array($method, $allowed[$resource])) {
            // The listener is not configured for the current method/resource combination
            return;
        }
        $origin = $request->headers->get('Origin');
        // Vary on Origin to prevent caching allowed/disallowed requests
        $event->getResponse()->setVary('Origin', false);
        // Fall back if the passed origin is not allowed
        if (!$origin || !$this->originIsAllowed($origin)) {
            return;
        }
        // Flag this as an allowed request
        $this->requestAllowed = true;
        $event->getResponse()->headers->add(['Access-Control-Allow-Origin' => $origin]);
    }

 /**
  * @covers Imbo\EventListener\Cors::invoke
  */
 public function testAddsVaryHeaderContainingOriginRegardlessOfAllowedStatus()
 {
     $this->request->expects($this->any())->method('getMethod')->will($this->returnValue('GET'));
     $route = $this->getMock('Imbo\\Router\\Route');
     $route->expects($this->any())->method('__toString')->will($this->returnValue('index'));
     $this->request->expects($this->any())->method('getRoute')->will($this->returnValue($route));
     // Allowed
     $listener = new Cors(['allowedOrigins' => ['http://imbo-project.org']]);
     $event = $this->getMock('Imbo\\EventManager\\Event');
     $event->expects($this->any())->method('getRequest')->will($this->returnValue($this->request));
     $response = $this->getMock('Imbo\\Http\\Response\\Response');
     $response->expects($this->once())->method('setVary')->with('Origin', false);
     $event->expects($this->any())->method('getResponse')->will($this->returnValue($response));
     $listener->invoke($event);
     // Disallowed
     $listener = new Cors(['allowedOrigins' => []]);
     $event = $this->getMock('Imbo\\EventManager\\Event');
     $event->expects($this->any())->method('getRequest')->will($this->returnValue($this->request));
     $response = $this->getMock('Imbo\\Http\\Response\\Response');
     $response->expects($this->once())->method('setVary')->with('Origin', false);
     $event->expects($this->any())->method('getResponse')->will($this->returnValue($response));
     $listener->invoke($event);
 }