Exploring Essential Services for Dependency Injection in Drupal 9, 10 Controllers and Forms

Drupal 9's architecture allows for seamless integration of services into controllers and forms using dependency injection. Here's a curated list of crucial services that can be effortlessly injected, enhancing the functionality and flexibility of your Drupal 9,10 application:

1. Database Services:
   • database: Drupal\Core\Database\Connection
   • entity_field.manager: Drupal\Core\Entity\EntityFieldManager
   • entity_type.manager: Drupal\Core\Entity\EntityTypeManagerInterface
2. File Handling Services:
   • file_system: Drupal\Core\File\FileSystemInterface
   • file.mime_type.guesser: Drupal\Core\File\MimeType\MimeTypeGuesserInterface
3. User and Access Services:
   • current_user: Drupal\Core\Session\AccountInterface
   • access_check.csrf: Drupal\Core\Access\CsrfTokenGeneratorInterface
   • access_arguments_resolver_factory: Drupal\Core\Access\AccessArgumentsResolverFactoryInterface
4. Configuration Services:
   • config.factory: Drupal\Core\Config\ConfigFactoryInterface
   • config: Drupal\Core\Config\ConfigManagerInterface
5. Routing and Path Services:
   • path.validator: Drupal\Core\Routing\RoutePathValidatorInterface
   • router.admin_context: Drupal\Core\Routing\AdminContext
6. Entity Services:
   • entity.repository: Drupal\Core\Entity\EntityRepositoryInterface
   • entity_type.bundle.info: Drupal\Core\Entity\EntityTypeBundleInfoInterface
7. State Handling Services:
   • state: Drupal\Core\State\StateInterface
   • keyvalue: Drupal\Core\KeyValueStore\KeyValueFactoryInterface
8. Logger and Error Handling Services:
   • logger.channel: Drupal\Core\Logger\LoggerChannelInterface
   • messenger: Drupal\Core\Messenger\MessengerInterface
9. Caching Services:
   • cache.backend: Drupal\Core\Cache\CacheBackendInterface
   • cache_tags.invalidator: Drupal\Core\Cache\CacheTagsInvalidatorInterface
10. Translation Services:
    • string_translation: Drupal\Core\StringTranslation\TranslationInterface
    • translation_manager: Drupal\Core\StringTranslation\TranslationManagerInterface
11. Mail Services:
    • mail.manager: Drupal\Core\Mail\MailManagerInterface
    • mail: Drupal\Core\Mail\MailManagerInterface (alias for mail.manager)
12. Event Dispatching Services:
    • event_dispatcher: Symfony\Component\EventDispatcher\EventDispatcherInterface
    • entity_display.repository: Drupal\Core\Entity\EntityDisplayRepositoryInterface
13. Request and Response Services:
    • request_stack: Symfony\Component\HttpFoundation\RequestStack
    • current_route_match: Drupal\Core\Routing\RouteMatchInterface
14. Theme Services:
    • theme.manager: Drupal\Core\Theme\ThemeManagerInterface
    • theme_handler: Drupal\Core\Extension\ThemeHandlerInterface
15. File Transfer Services:
    • file_system: Drupal\Core\File\FileSystemInterface
    • stream_wrapper_manager: Drupal\Core\StreamWrapper\StreamWrapperManagerInterface

These services encompass a diverse range of functionalities, aiding in the development of robust and feature-rich Drupal 9, 10 applications. Injecting these services into controllers or forms using dependency injection streamlines development and facilitates seamless integration of various Drupal components.