MediaWiki 1.30.2

[autoinstallsdev/mediawiki.git] / includes / config / ConfigFactory.php

diff --git a/includes/config/ConfigFactory.php b/includes/config/ConfigFactory.php
new file mode 100644 (file)
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+++ b/includes/config/ConfigFactory.php
@@ -0,0 +1,150 @@
+<?php
+
+/**
+ * Copyright 2014
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ */
+use MediaWiki\Services\SalvageableService;
+use Wikimedia\Assert\Assert;
+
+/**
+ * Factory class to create Config objects
+ *
+ * @since 1.23
+ */
+class ConfigFactory implements SalvageableService {
+
+       /**
+        * Map of config name => callback
+        * @var array
+        */
+       protected $factoryFunctions = [];
+
+       /**
+        * Config objects that have already been created
+        * name => Config object
+        * @var array
+        */
+       protected $configs = [];
+
+       /**
+        * @deprecated since 1.27, use MediaWikiServices::getConfigFactory() instead.
+        *
+        * @return ConfigFactory
+        */
+       public static function getDefaultInstance() {
+               return \MediaWiki\MediaWikiServices::getInstance()->getConfigFactory();
+       }
+
+       /**
+        * Re-uses existing Cache objects from $other. Cache objects are only re-used if the
+        * registered factory function for both is the same. Cache config is not copied,
+        * and only instances of caches defined on this instance with the same config
+        * are copied.
+        *
+        * @see SalvageableService::salvage()
+        *
+        * @param SalvageableService $other The object to salvage state from. $other must have the
+        * exact same type as $this.
+        */
+       public function salvage( SalvageableService $other ) {
+               Assert::parameterType( self::class, $other, '$other' );
+
+               /** @var ConfigFactory $other */
+               foreach ( $other->factoryFunctions as $name => $otherFunc ) {
+                       if ( !isset( $this->factoryFunctions[$name] ) ) {
+                               continue;
+                       }
+
+                       // if the callback function is the same, salvage the Cache object
+                       // XXX: Closures are never equal!
+                       if ( isset( $other->configs[$name] )
+                               && $this->factoryFunctions[$name] == $otherFunc
+                       ) {
+                               $this->configs[$name] = $other->configs[$name];
+                               unset( $other->configs[$name] );
+                       }
+               }
+
+               // disable $other
+               $other->factoryFunctions = [];
+               $other->configs = [];
+       }
+
+       /**
+        * @return string[]
+        */
+       public function getConfigNames() {
+               return array_keys( $this->factoryFunctions );
+       }
+
+       /**
+        * Register a new config factory function.
+        * Will override if it's already registered.
+        * Use "*" for $name to provide a fallback config for all unknown names.
+        * @param string $name
+        * @param callable|Config $callback A factory callabck that takes this ConfigFactory
+        *        as an argument and returns a Config instance, or an existing Config instance.
+        * @throws InvalidArgumentException If an invalid callback is provided
+        */
+       public function register( $name, $callback ) {
+               if ( !is_callable( $callback ) && !( $callback instanceof Config ) ) {
+                       throw new InvalidArgumentException( 'Invalid callback provided' );
+               }
+
+               unset( $this->configs[$name] );
+               $this->factoryFunctions[$name] = $callback;
+       }
+
+       /**
+        * Create a given Config using the registered callback for $name.
+        * If an object was already created, the same Config object is returned.
+        * @param string $name Name of the extension/component you want a Config object for
+        *                     'main' is used for core
+        * @throws ConfigException If a factory function isn't registered for $name
+        * @throws UnexpectedValueException If the factory function returns a non-Config object
+        * @return Config
+        */
+       public function makeConfig( $name ) {
+               if ( !isset( $this->configs[$name] ) ) {
+                       $key = $name;
+                       if ( !isset( $this->factoryFunctions[$key] ) ) {
+                               $key = '*';
+                       }
+                       if ( !isset( $this->factoryFunctions[$key] ) ) {
+                               throw new ConfigException( "No registered builder available for $name." );
+                       }
+
+                       if ( $this->factoryFunctions[$key] instanceof Config ) {
+                               $conf = $this->factoryFunctions[$key];
+                       } else {
+                               $conf = call_user_func( $this->factoryFunctions[$key], $this );
+                       }
+
+                       if ( $conf instanceof Config ) {
+                               $this->configs[$name] = $conf;
+                       } else {
+                               throw new UnexpectedValueException( "The builder for $name returned a non-Config object." );
+                       }
+               }
+
+               return $this->configs[$name];
+       }
+
+}