What are the Drupal 8 Services

In Drupal 8 a service is any object managed by the services container.

Drupal 8 introduces the concept of services to decouple reusable functionality and makes these services pluggable and replaceable by registering them with a service container.

As a developer, it is best practice to access any of the services provided by Drupal via the service container to ensure the decoupled nature of these systems is respected.

Example of core services:

Generate a new UUID with uuid service

$uuid = \Drupal::service('uuid')->generate();

get current path with path.current service

$current_path = \Drupal::service('path.current')->getPath();

get alias of a path with path.alias_manager service

$alias = \Drupal::service('path.alias_manager')->getAliasByPath($current_path);

Switch user sessions using Account Switcher service

// Call the account switcher service
  $accountSwitcher = \Drupal::service('account_switcher');

// Switch to the other user
  $account = \Drupal\user\Entity\User::load(1);
  $accountSwitcher->switchTo($account);

Drupal 8's core services are located on : /core/core.services.yml

Example core services:

...
authentication:
  class: Drupal\Core\Authentication\AuthenticationManager
  arguments: ['@authentication_collector']
authentication_collector:
  class: Drupal\Core\Authentication\AuthenticationCollector
  tags:
    - { name: service_collector, tag: authentication_provider, call: addProvider }
authentication_subscriber:
  class: Drupal\Core\EventSubscriber\AuthenticationSubscriber
  arguments: ['@authentication', '@current_user']
  tags:
    - { name: event_subscriber }
account_switcher:
  class: Drupal\Core\Session\AccountSwitcher
  arguments: ['@current_user', '@session_handler.write_safe']
user_permissions_hash_generator:
  class: Drupal\Core\Session\PermissionsHashGenerator
  arguments: ['@private_key', '@cache.bootstrap', '@cache.static']
current_user:
  class: Drupal\Core\Session\AccountProxy
  arguments: ['@event_dispatcher']
session_configuration:
  class: Drupal\Core\Session\SessionConfiguration
  arguments: ['%session.storage.options%']

...

To get All available services list

$services = \Drupal::getContainer()->getServiceIds();