Regenerate image styles

Question

I'm currently using Drupal 8.2.3 for my website design. My aim is to use it for publishing my blogs to social media sites, such as Facebook, Twitter, LinkedIN, etc. With that in mind, i'm using image styles to create OpenGraph and Twitter meta tags in my blog posts to properly display content on various platforms.

The problem comes when I make a change to the imagestyle. When I flush the contents, it doesn't automatically regenerate the imagestyle content for my metadata. Is there a way to automatically regenerate the imagestyles and content?

Any help much appreciated.

Answer 1

There is a setting to flush the image style at admin/config/media/image-styles:

Or you can use drush:

drush image-flush --all (flush all styles)
drush image-flush thumbnail (flush thumbnail style)

Answer 2

If you are using Drupal Console (and let's face it, why not?) then you can use:

drupal image:styles:flush image_style

Documenation: https://docs.drupalconsole.com/en/commands/image-styles-flush.html

Answer 3

The problem comes when I make a change to the imagestyle. When I flush the contents, it doesn't automatically regenerate the imagestyle content for my metadata. Is there a way to automatically regenerate the imagestyles and content?

I have a couple of questions to you:

• What kind of changes you make to the image style?
• What does flushint the contents mean?
• By imagestyle content you mean the derivated image from the original one? (so generated image file itself)

Answer 4

Sometimes - images are not showing, when seeing files in contents.

This mostly caused by server permissions.

For CentOS/Redhat/Fedora/Rocky Linux systems :

chown -R apache:apache /var/www/html/demodrupal/sites/default/
chcon -R -t httpd_sys_rw_content_t sites/default/

Two commands are required/

Answer 5

It seems you want to generate proper metatags for your node pages (blogs). To generate them dynamically i propose to add to your module.module file next code with hook_entity_view function:

  function your_module_entity_view(array &$build, \Drupal\Core\Entity\EntityInterface $entity, \Drupal\Core\Entity\Display\EntityViewDisplayInterface $display, $view_mode) {

  if ($entity->getEntityTypeId() == 'node') {
      $bundle = $entity->bundle();
      switch ($bundle){
          case 'blog':
              $image = $entity->get('field_image');
              $image_id = $image->getValue()[0]['target_id'];
              $image_file = \Drupal\file\Entity\File::load($image_id);
              $uri = $image_file->uri->value;
              $facebook_image_url = Drupal\image\Entity\ImageStyle::load('your_facebook_style')->buildUrl($uri);
              $facebook_metatag = [
                  '#tag' => 'meta',
                  '#attributes' => [
                    'property' => 'og:image',
                    'content' => $facebook_image_url,
                  ],
                ];
               $build['#attached']['html_head'][] = [$facebook_metatag, 'facebook_metatag'];
// the same for other social networks:

$twitter_image_url = Drupal\image\Entity\ImageStyle::load('your_twitter_style')->buildUrl($uri);
//etc
                  break;

          }

      }

    }

And you get this metatag type meta property="og:image" content="http://static01.nyt.com/images/2015/02/19/arts/international/19iht-btnumbers19A/19iht-btnumbers19A-facebookJumbo-v2.jpg" Also you can add any metatag in such a manner:

 $facebook_metatag = [
    '#tag' => 'meta',
    '#attributes' => [
             'property' => 'og:title',
             'content' => $your_node_title,
          ],
   ];
   $build['#attached']['html_head'][] = [$facebook_metatag, 'facebook_metatag'];