Limit available image styles for image related blocks

Adds an accordion to the "Gutenberg Experience" settings on content type edit screen with an option to filter allowed image styles.

Adds missing code to filter image sizes in gutenberg sidebar

Fixes 'original' being shown when it's not selected in allowed styles

Thanks for working on this! This capability would be great!

I installed the patch #6 and got the following error:

Warning: foreach() argument must be of type array|object, null given in gutenberg_form_alter() (line 281 of /var/www/html/web/modules/contrib/gutenberg/gutenberg.module)
#0 /var/www/html/web/core/includes/bootstrap.inc(347): _drupal_error_handler_real(2, 'foreach() argum...', '/var/www/html/w...', 281)
#1 /var/www/html/web/modules/contrib/gutenberg/gutenberg.module(281): _drupal_error_handler(2, 'foreach() argum...', '/var/www/html/w...', 281)
#2 /var/www/html/web/core/lib/Drupal/Core/Extension/ModuleHandler.php(562): gutenberg_form_alter(Array, Object(Drupal\Core\Form\FormState), 'node_type_edit_...')
#3 /var/www/html/web/core/lib/Drupal/Core/Form/FormBuilder.php(838): Drupal\Core\Extension\ModuleHandler->alter('form', Array, Object(Drupal\Core\Form\FormState), 'node_type_edit_...')
#4 /var/www/html/web/core/lib/Drupal/Core/Form/FormBuilder.php(282): Drupal\Core\Form\FormBuilder->prepareForm('node_type_edit_...', Array, Object(Drupal\Core\Form\FormState))
#5 /var/www/html/web/core/lib/Drupal/Core/Controller/FormController.php(73): Drupal\Core\Form\FormBuilder->buildForm(Object(Drupal\node\NodeTypeForm), Object(Drupal\Core\Form\FormState))
#6 [internal function]: Drupal\Core\Controller\FormController->getContentResult(Object(Symfony\Component\HttpFoundation\Request), Object(Drupal\Core\Routing\RouteMatch))
#7 /var/www/html/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(123): call_user_func_array(Array, Array)
#8 /var/www/html/web/core/lib/Drupal/Core/Render/Renderer.php(580): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
#9 /var/www/html/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(124): Drupal\Core\Render\Renderer->executeInRenderContext(Object(Drupal\Core\Render\RenderContext), Object(Closure))
#10 /var/www/html/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(97): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array)
#11 /var/www/html/vendor/symfony/http-kernel/HttpKernel.php(169): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
#12 /var/www/html/vendor/symfony/http-kernel/HttpKernel.php(81): Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object(Symfony\Component\HttpFoundation\Request), 1)
#13 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/Session.php(58): Symfony\Component\HttpKernel\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#14 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(48): Drupal\Core\StackMiddleware\Session->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#15 /var/www/html/web/core/modules/page_cache/src/StackMiddleware/PageCache.php(106): Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#16 /var/www/html/web/core/modules/page_cache/src/StackMiddleware/PageCache.php(85): Drupal\page_cache\StackMiddleware\PageCache->pass(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#17 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(48): Drupal\page_cache\StackMiddleware\PageCache->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#18 /var/www/html/web/core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(51): Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#19 /var/www/html/vendor/stack/builder/src/Stack/StackedHttpKernel.php(23): Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#20 /var/www/html/web/core/lib/Drupal/Core/DrupalKernel.php(718): Stack\StackedHttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#21 /var/www/html/web/index.php(19): Drupal\Core\DrupalKernel->handle(Object(Symfony\Component\HttpFoundation\Request))
#22 {main}

The list to select the image styles did work, and in gutenberg the options are only showing what I chose, but the image style is not being applied when i save the page.

Added a small fix that will prevent showing warnings in the editor whenever a new image style is added.

Here's the patch in #8 rerolled for Gutenberg 3.0.

We've been running that patch for ages now.

Finally merged to 2.x and 3.0.x. Great work y'all 😉

Just a notice for anyone who gets a warning message as follows after upgrading to 3.0.3:

Warning: Undefined variable $sizes in gutenberg_form_node_form_alter() (line 765 of modules/contrib/gutenberg/gutenberg.module).

You will need to re-save the content type configuration for all content types using Gutenberg to set the allowed styles and clear this warning.

@tkiehne This has fixed in #3467986: Undefined variable $sizes in gutenberg_form_node_form_alter().

But I have another one as well, if you just updated without saving all node forms again.

 Warning: Trying to access array offset on null in /var/www/html/web/modules/contrib/gutenberg/gutenberg.module on line 

So it's actually better to do the following

$allowed_styles = $config->get($node_type . '_allowed_image_styles') ?? [];

In addition there is the following:

  if (!empty($styles)) {
    foreach ($styles as $style) {
      if ($allowed_styles[$style->getName()]) {
        $sizes[] = [
          'slug' => $style->getName(),
          'name' => $style->label(),
        ];
      }
    }
  }

If the site introduces a new image style after the node form has been saved, this will also lead to a warning.

Thanks @marcofernandes

There's a new issue caused by this change: #3471570: Warning: Trying to access array offset on value of type null in gutenberg_form_node_form_alter() (line 578 of gutenberg.module).

I explained my findings here: https://www.drupal.org/project/gutenberg/issues/3471570#comment-15786262

Following this change, the Original (full) image style is no longer visible in 3.x.