X-Git-Url: https://git.heureux-cyclage.org/?a=blobdiff_plain;f=docs%2Finjection.txt;h=83a14c730dcc1662c5f54f6cfca18eeeee85372e;hb=31c334794c8164e44353e22aed71bb27caca80e3;hp=e0466c44a55fbd11da80e942ac3d9af865120c15;hpb=a0803c9bc551631c8a35bf2d99705a724cb62039;p=lhc%2Fweb%2Fwiklou.git

diff --git a/docs/injection.txt b/docs/injection.txt
index e0466c44a5..83a14c730d 100644
--- a/docs/injection.txt
+++ b/docs/injection.txt
@@ -60,6 +60,27 @@ MediaWikiServices::getInstance() should ideally be accessed only in "static
 entry points" such as hook handler functions. See "Migration" below.
 
 
+== Service Reset ==
+
+Services get their configuration injected, and changes to global
+configuration variables will not have any effect on services that were already
+instantiated. This would typically be the case for low level services like
+the ConfigFactory or the ObjectCacheManager, which are used during extension
+registration. To address this issue, Setup.php resets the global service
+locator instance by calling MediaWikiServices::resetGlobalInstance() once
+configuration and extension registration is complete.
+
+Note that "unmanaged" legacy services services that manage their own singleton
+must not keep references to services managed by MediaWikiServices, to allow a
+clean reset. After the global MediaWikiServices instance got reset, any such
+references would be stale, and using a stale service will result in an error.
+
+Services should either have all dependencies injected and be themselves managed
+by MediaWikiServices, or they should use the Service Locator pattern, accessing
+service instances via the global MediaWikiServices instance state when needed.
+This ensures that no stale service references remain after a reset.
+
+
 == Configuration ==
 
 When the default MediaWikiServices instance is created, a Config object is
@@ -198,7 +219,7 @@ already known to MediaWikiServices (if not, see above).
   variables.
 * Add a constructor to MyExtHooks that takes a Bar service as a parameter.
 * Add a static method called newFromGlobalState() with no parameters. It should
-  just return new MyExtHooks( MediaWikiServices::getBar() ).
+  just return new MyExtHooks( MediaWikiServices::getInstance()->getBar() ).
 * The original static handler method onFoo( $x ) is then implemented as
   self::newFromGlobalState()->doFoo( $x ).