interface ServiceSubscriberInterface

A ServiceSubscriber exposes its dependencies via the static {@link getSubscribedServices} method.

The getSubscribedServices method returns an array of service types required by such instances, optionally keyed by the service names used internally. Service types that start with an interrogation mark "?" are optional, while the other ones are mandatory service dependencies.

The injected service locators SHOULD NOT allow access to any other services not specified by the method.

It is expected that ServiceSubscriber instances consume PSR-11-based service locators internally. This interface does not dictate any injection method for these service locators, although constructor injection is recommended.

Methods

static array
getSubscribedServices()

Returns an array of service types required by such instances, optionally keyed by the service names used internally.

Details

static array getSubscribedServices()

Returns an array of service types required by such instances, optionally keyed by the service names used internally.

For mandatory dependencies:

  • array('logger' => 'Psr\Log\LoggerInterface') means the objects use the "logger" name internally to fetch a service which must implement Psr\Log\LoggerInterface.
  • array('loggers' => 'Psr\Log\LoggerInterface[]') means the objects use the "loggers" name internally to fetch an iterable of Psr\Log\LoggerInterface instances.
  • array('Psr\Log\LoggerInterface') is a shortcut for
  • array('Psr\Log\LoggerInterface' => 'Psr\Log\LoggerInterface')

otherwise:

  • array('logger' => '?Psr\Log\LoggerInterface') denotes an optional dependency
  • array('loggers' => '?Psr\Log\LoggerInterface[]') denotes an optional iterable dependency
  • array('?Psr\Log\LoggerInterface') is a shortcut for
  • array('Psr\Log\LoggerInterface' => '?Psr\Log\LoggerInterface')

Return Value

array The required service types, optionally keyed by service names