DOMPDFModule\View\Strategy\PdfStrategy::injectResponse PHP Method

    public function injectResponse(ViewEvent $event)
    {
        $renderer = $event->getRenderer();
        if ($renderer !== $this->renderer) {
            // Discovered renderer is not ours; do nothing
            return;
        }
        $result = $event->getResult();
        if (!is_string($result)) {
            // @todo Potentially throw an exception here since we should *always* get back a result.
            return;
        }
        $response = $event->getResponse();
        $response->setContent($result);
        $response->getHeaders()->addHeaderLine('content-type', 'application/pdf');
        $fileName = $event->getModel()->getOption('filename');
        if (isset($fileName)) {
            if (substr($fileName, -4) != '.pdf') {
                $fileName .= '.pdf';
            }
            $response->getHeaders()->addHeaderLine('Content-Disposition', 'attachment; filename=' . $fileName);
        }
    }

 public function testResponseHeadersWithFileName()
 {
     $model = new PdfModel();
     $model->setTemplate('basic.phtml');
     $model->setOption('filename', 'testPdfFileName');
     $this->event->setModel($model);
     $this->event->setResponse($this->response);
     $this->event->setRenderer($this->renderer);
     $this->event->setResult($this->renderer->render($model));
     $this->strategy->injectResponse($this->event);
     $headers = $this->event->getResponse()->getHeaders();
     $contentDisposition = $headers->get('Content-Disposition');
     $this->assertInstanceOf('Zend\\Http\\Header\\ContentDisposition', $contentDisposition);
     $this->assertEquals($contentDisposition->getFieldValue(), 'attachment; filename=testPdfFileName.pdf');
     ob_end_flush();
     // Clear out any buffers held by renderers.
 }