Same name in other branches

1. 9 core/modules/image/src/Controller/ImageStyleDownloadController.php \Drupal\image\Controller\ImageStyleDownloadController::deliver()
2. 10 core/modules/image/src/Controller/ImageStyleDownloadController.php \Drupal\image\Controller\ImageStyleDownloadController::deliver()
3. 11.x core/modules/image/src/Controller/ImageStyleDownloadController.php \Drupal\image\Controller\ImageStyleDownloadController::deliver()

Generates a derivative, given a style and image path.

After generating an image, transfer it to the requesting agent.

Parameters

\Symfony\Component\HttpFoundation\Request $request: The request object.

string $scheme: The file scheme, defaults to 'private'.

\Drupal\image\ImageStyleInterface $image_style: The image style to deliver.

Return value

\Symfony\Component\HttpFoundation\BinaryFileResponse|\Symfony\Component\HttpFoundation\Response The transferred file as response or some error response.

Throws

\Symfony\Component\HttpKernel\Exception\NotFoundHttpException Thrown when the file request is invalid.

\Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException Thrown when the user does not have access to the file.

\Symfony\Component\HttpKernel\Exception\ServiceUnavailableHttpException Thrown when the file is still being generated.

1 string reference to 'ImageStyleDownloadController::deliver'

image.routing.yml in core/modules/image/image.routing.yml

core/modules/image/image.routing.yml

File

core/modules/image/src/Controller/ImageStyleDownloadController.php, line 95

Class

ImageStyleDownloadController

Defines a controller to serve image styles.

Namespace

Drupal\image\Controller

Code

public function deliver(Request $request, $scheme, ImageStyleInterface $image_style) {
    $target = $request->query
        ->get('file');
    $image_uri = $scheme . '://' . $target;
    // Check that the style is defined, the scheme is valid, and the image
    // derivative token is valid. Sites which require image derivatives to be
    // generated without a token can set the
    // 'image.settings:allow_insecure_derivatives' configuration to TRUE to
    // bypass the latter check, but this will increase the site's vulnerability
    // to denial-of-service attacks. To prevent this variable from leaving the
    // site vulnerable to the most serious attacks, a token is always required
    // when a derivative of a style is requested.
    // The $target variable for a derivative of a style has
    // styles/<style_name>/... as structure, so we check if the $target variable
    // starts with styles/.
    $valid = !empty($image_style) && $this->streamWrapperManager
        ->isValidScheme($scheme);
    if (!$this->config('image.settings')
        ->get('allow_insecure_derivatives') || strpos(ltrim($target, '\\/'), 'styles/') === 0) {
        $valid &= hash_equals($image_style->getPathToken($image_uri), $request->query
            ->get(IMAGE_DERIVATIVE_TOKEN, ''));
    }
    if (!$valid) {
        // Return a 404 (Page Not Found) rather than a 403 (Access Denied) as the
        // image token is for DDoS protection rather than access checking. 404s
        // are more likely to be cached (e.g. at a proxy) which enhances
        // protection from DDoS.
        throw new NotFoundHttpException();
    }
    $derivative_uri = $image_style->buildUri($image_uri);
    $headers = [];
    // If using the private scheme, let other modules provide headers and
    // control access to the file.
    if ($scheme == 'private') {
        $headers = $this->moduleHandler()
            ->invokeAll('file_download', [
            $image_uri,
        ]);
        if (in_array(-1, $headers) || empty($headers)) {
            throw new AccessDeniedHttpException();
        }
    }
    // Don't try to generate file if source is missing.
    if (!file_exists($image_uri)) {
        // If the image style converted the extension, it has been added to the
        // original file, resulting in filenames like image.png.jpeg. So to find
        // the actual source image, we remove the extension and check if that
        // image exists.
        $path_info = pathinfo($image_uri);
        $converted_image_uri = $path_info['dirname'] . DIRECTORY_SEPARATOR . $path_info['filename'];
        if (!file_exists($converted_image_uri)) {
            $this->logger
                ->notice('Source image at %source_image_path not found while trying to generate derivative image at %derivative_path.', [
                '%source_image_path' => $image_uri,
                '%derivative_path' => $derivative_uri,
            ]);
            return new Response($this->t('Error generating image, missing source file.'), 404);
        }
        else {
            // The converted file does exist, use it as the source.
            $image_uri = $converted_image_uri;
        }
    }
    // Don't start generating the image if the derivative already exists or if
    // generation is in progress in another thread.
    if (!file_exists($derivative_uri)) {
        $lock_name = 'image_style_deliver:' . $image_style->id() . ':' . Crypt::hashBase64($image_uri);
        $lock_acquired = $this->lock
            ->acquire($lock_name);
        if (!$lock_acquired) {
            // Tell client to retry again in 3 seconds. Currently no browsers are
            // known to support Retry-After.
            throw new ServiceUnavailableHttpException(3, 'Image generation in progress. Try again shortly.');
        }
    }
    // Try to generate the image, unless another thread just did it while we
    // were acquiring the lock.
    $success = file_exists($derivative_uri) || $image_style->createDerivative($image_uri, $derivative_uri);
    if (!empty($lock_acquired)) {
        $this->lock
            ->release($lock_name);
    }
    if ($success) {
        $image = $this->imageFactory
            ->get($derivative_uri);
        $uri = $image->getSource();
        $headers += [
            'Content-Type' => $image->getMimeType(),
            'Content-Length' => $image->getFileSize(),
        ];
        // \Drupal\Core\EventSubscriber\FinishResponseSubscriber::onRespond()
        // sets response as not cacheable if the Cache-Control header is not
        // already modified. We pass in FALSE for non-private schemes for the
        // $public parameter to make sure we don't change the headers.
        return new BinaryFileResponse($uri, 200, $headers, $scheme !== 'private');
    }
    else {
        $this->logger
            ->notice('Unable to generate the derived image located at %path.', [
            '%path' => $derivative_uri,
        ]);
        return new Response($this->t('Error generating image.'), 500);
    }
}

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