MediaWiki\Hook\MediaWikiServicesHook Interface Reference

This is a hook handler interface, see docs/Hooks.md. More...

Inherited by MediaWiki\HookContainer\HookRunner.

Public Member Functions
	onMediaWikiServices ( $services)
	This hook is called when a global MediaWikiServices instance is initialized.

Detailed Description

This is a hook handler interface, see docs/Hooks.md.

Use the hook name "MediaWikiServices" to register handlers implementing this interface.

Warning

Implementations of this interface must not have services injected into their constructor! This is because this hook runs while the service container is still being initialized, so any services it asks for might get instantiated based on incomplete configuration and wiring.

Stability: stable

to implement

Definition at line 19 of file MediaWikiServicesHook.php.

Member Function Documentation

onMediaWikiServices()

MediaWiki\Hook\MediaWikiServicesHook::onMediaWikiServices

(

$services

)

This hook is called when a global MediaWikiServices instance is initialized.

Extensions may use this to define, replace, or wrap services. However, the preferred way to define a new service is the $wgServiceWiringFiles array.

Global configuration variables are safe to change at this point. All other hooks run after some of those variables have been copied during service initialization already, so variable changes in those hooks might have no effect or lead to inconsistencies.

Warning

Implementations must not immediately access services instances from the service container $services, since the service container is not fully initialized at the time when the hook is called. However, callbacks that are used as service instantiators or service manipulators may access service instances.

As an exception from the above, the following services are safe to access:

• MainConfig and ConfigFactory;
• HookContainer (but all hooks run inside a MediaWikiServices hook handler MUST use the 'noServices' option);
• extension services that have explicitly been documented as safe, and follow the same rules in their service wiring logic.

Example:

function onMediaWikiServices( $services ) {
    // The service wiring and configuration in $services may be incomplete at this time,
    // do not access services yet!
    // At this point, we can only manipulate the wiring, not use it!
 
    $services->defineService(
       'MyCoolService',
        function( MediaWikiServices $container ) {
            // It's ok to access services inside this callback, since the
            // service container will be fully initialized when it is called!
            return new MyCoolService( $container->getPageLookup() );
        }
    );
 
    $services->addServiceManipulator(
        'SlotRoleRegistry',
        function ( SlotRoleRegistry $service, MediaWikiServices $container ) {
            // ...
        }
    );
 
    $services->redefineService(
        'StatsdDataFactory',
        function ( MediaWikiServices $container ) {
            // ...
        }
    );
}

Since

1.35

Parameters

MediaWikiServices

$services

Returns

bool|void True or no return value to continue or false to abort

Implemented in MediaWiki\HookContainer\HookRunner.

---

The documentation for this interface was generated from the following file:

• includes/Hook/MediaWikiServicesHook.php