Acquia Certified Back End Specialist D10 Exam Preparation Material | Acquia Certified Back End Specialist - Drupal 10

(Plugin API - Context API)
Scenario:
You are building a custom Block plugin ( @Block ). The block's logic requires the fully loaded Node object of the page currently being viewed.
What is the recommended Drupal Plugin API approach to ensure your block automatically receives the Node object?
A . Add context_definitions = { "node" = @ContextDefinition("entity:node") } to the block's plugin annotation.
B . Implement ContainerFactoryPluginInterface , inject the current_route_match service, and extract the node parameter manually inside the build() method to ensure proper dependency injection.
C . Implement hook_block_view_alter() to attach the node object to the block's render array before it is built.
D . Use \Drupal::request()->attributes->get('node') directly inside build() .

(Cache API - Custom Cache Contexts)
Scenario:
You want to cache a custom block differently depending on whether the current HTTP request has a custom header X-My-Header .
How do you implement this new caching rule so it can be used in render arrays as ['#cache' => ['contexts' => ['my_header']]] ?
A . Add the header to the $settings['cache_contexts'] array in settings.php .
B . Call \Drupal::cache()->setContext('my_header', $request->headers->get('X-My-Header')) inside the block's build() method.
C . Implement hook_cache_context_info_alter() to append the header to the global registry.
D . Create a custom class implementing CacheContextInterface to evaluate the request header, and register it in services.yml as a service tagged with cache.context .

(Configuration API - Override Free)
Scenario:
You are working with a custom Configuration Entity type called Robot . You need to programmatically load a Robot config entity (ID: optimus ), modify its power_level property, and save it to the database.
However, your site has a settings.php file that overrides this specific value: $config['my_module.robot.optimus']['power_level'] = 9000; .
How must you load this Config Entity to ensure you are modifying the original database configuration, rather than accidentally saving the temporary settings.php override back to the database?
A . \Drupal::entityTypeManager()->getStorage('robot')->loadOverrideFree('optimus');
B . \Drupal::configFactory()->getEditable('my_module.robot.optimus')
C . Instantiate a new ConfigEntityStorage controller and pass a boolean flag TRUE to the load() method to instruct the database abstraction layer to ignore any in-memory state overrides.
D . Temporarily unset the $config global variable in your PHP script before loading the entity.

(Event Subscriber Registration)
Scenario:
You have written a class RedirectSubscriber that correctly implements EventSubscriberInterface to intercept Symfony kernel request events. However, the logic is never executed during a page load.
Your my_module.services.yml looks like this:

services:
my_module.redirect_subscriber:
class: Drupal\my_module\EventSubscriber\RedirectSubscriber

What critical metadata is missing from the service definition to ensure Drupal registers it as an active event subscriber?
A . autowire: true
B . tags: [{ name: event_subscriber }]
C . type: subscriber
D . events: ['kernel.request']

(Theme System - Dynamic Theme Selection)
Scenario:
The marketing team requires that any user visiting a URL with a specific query parameter (e.g., ?campaign=summer_sale ) must see the site rendered with a completely different theme ( campaign_theme ) instead of the default frontend theme.
How do you dynamically switch the active theme for these specific requests in Drupal 10?
A . Implement hook_custom_theme() and return 'campaign_theme' when the query parameter is present in \Drupal::request() .
B . Create a service tagged with theme_negotiator that implements ThemeNegotiatorInterface , check the request in the applies() method, and return the theme name in determineActiveTheme() .
C . Implement hook_theme_registry_alter() to intercept the template engine rendering process, inspect the current request's route parameters, and forcibly swap the active theme variable stored in the global registry state before the HTML is compiled.
D . Call \Drupal::theme()->setActiveTheme('campaign_theme') inside a custom EventSubscriber listening to KernelEvents::REQUEST .