function media_acquiadam_image_style_deliver in Media: Acquia DAM 7

Implementation of image_style_deliver().

Allows serving images from outside of the file_managed table.

Parameters

string $styleName: The image style being requested.

AcquiaDAM_Assets_AbstractAsset $asset: The asset to view an image of.

Return value

int A menu response code.

1 string reference to 'media_acquiadam_image_style_deliver'

media_acquiadam_menu in ./media_acquiadam.module

Implements hook_menu().

File

includes/media_acquiadam.image.inc, line 21

Code for working with DAM image styles.

Code

function media_acquiadam_image_style_deliver($styleName, AcquiaDAM_Assets_AbstractAsset $asset) {

  // Drupal does not allow multiple _load style menu arguments so we need to
  // manually load this here.
  $style = image_style_load($styleName);
  if (empty($style)) {
    return MENU_NOT_FOUND;
  }
  try {
    $image_uri = $asset
      ->getThumbnailUrl();
    if (empty($image_uri)) {
      return MENU_NOT_FOUND;
    }

    // Prime image styles before loading below.
    media_acquiadam_create_asset_image_derivatives($asset);
  } catch (Exception $x) {
    watchdog_exception('media_acquiadam', $x);
    return MENU_NOT_FOUND;
  }
  $derivative_uri = media_acquiadam_image_style_path($asset['id'], $style, $image_uri);

  // The rest of the logic is the same as contined within the original
  // remote_stream_wrapper function.
  // Don't start generating the image if the derivative already exists or if
  // generation is in progress in another thread.
  $lock_name = 'image_style_deliver:' . $style['name'] . ':' . drupal_hash_base64($image_uri);
  if (!is_file($derivative_uri)) {
    $lock_acquired = lock_acquire($lock_name);
    if (!$lock_acquired) {

      // Tell client to retry again in 3 seconds. Currently no browsers are known
      // to support Retry-After.
      drupal_add_http_header('Status', '503 Service Unavailable');
      drupal_add_http_header('Retry-After', 3);
      print t('Image generation in progress. Try again shortly.');
      drupal_exit();
    }
  }

  // Try to generate the image, unless another thread just did it while we were
  // acquiring the lock.
  $success = is_file($derivative_uri) || image_style_create_derivative($style, $image_uri, $derivative_uri);
  if (!empty($lock_acquired)) {
    lock_release($lock_name);
  }
  if ($success) {
    $image = image_load($derivative_uri);
    file_transfer($image->source, [
      'Content-Type' => $image->info['mime_type'],
      'Content-Length' => $image->info['file_size'],
    ]);
  }
  else {
    watchdog('media_acquiadam', 'Unable to generate the derived image located at %path.', [
      '%path' => $derivative_uri,
    ]);
    drupal_add_http_header('Status', '500 Internal Server Error');
    print t('Error generating image.');
    drupal_exit();
  }
}