search: Add 'SearchMappings' attribute to map canonical name to PHP class

This allows indirection between the values in $wgSearchType and
$wgSearchTypeAlternatives where the underlying class name
doesn't match the actual class name that subclasses
SearchEngine.

Bug: T250977
Change-Id: Ib9634128f07d428276e80a6f2f492b850eef17e8

8 files changed, 77 insertions, 7 deletions

diff --git a/docs/extension.schema.v1.json b/docs/extension.schema.v1.json
index e23f0ac7bc08..6730e6da6162 100644
--- a/docs/extension.schema.v1.json
+++ b/docs/extension.schema.v1.json
@@ -843,6 +843,10 @@
 			"type": "array",
 			"description": "DEPRECATED: Parser test suite files to be run by parserTests.php when no specific filename is passed to it"
 		},
+		"SearchMappings": {
+			"type": "object",
+			"description": "Mapping of search canonical names (used in $wgSearchType and $wgSearchTypeAlternatives) using the Object Factory specification"
+		},
 		"ServiceWiringFiles": {
 			"type": "array",
 			"description": "List of service wiring files to be loaded by the default instance of MediaWikiServices"
diff --git a/docs/extension.schema.v2.json b/docs/extension.schema.v2.json
index a1163c3bc232..78e1fabb3572 100644
--- a/docs/extension.schema.v2.json
+++ b/docs/extension.schema.v2.json
@@ -972,6 +972,10 @@
 			"type": "array",
 			"description": "DEPRECATED: Parser test suite files to be run by parserTests.php when no specific filename is passed to it"
 		},
+		"SearchMappings": {
+			"type": "object",
+			"description": "Mapping of search canonical names (used in $wgSearchType and $wgSearchTypeAlternatives) using the Object Factory specification"
+		},
 		"ServiceWiringFiles": {
 			"type": "array",
 			"description": "List of service wiring files to be loaded by the default instance of MediaWikiServices"
diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index b16280948022..6cc56dad76d1 100644
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -2030,18 +2030,28 @@ $wgDBadminpassword = null;
 
 /**
  * Search type.
+ *
  * Leave as null to select the default search engine for the
  * selected database type (eg SearchMySQL), or set to a class
  * name to override to a custom search engine.
+ *
+ * If the canonical name for the search engine doesn't match the class name
+ * (because it's namespaced for example), you can add a mapping for this in
+ * SearchMappings in extension.json.
  */
 $wgSearchType = null;
 
 /**
  * Alternative search types
+ *
  * Sometimes you want to support multiple search engines for testing. This
  * allows users to select their search engine of choice via url parameters
  * to Special:Search and the action=search API. If using this, there's no
  * need to add $wgSearchType to it, that is handled automatically.
+ *
+ * If the canonical name for the search engine doesn't match the class name
+ * (because it's namespaced for example), you can add a mapping for this in
+ * SearchMappings in extension.json.
  */
 $wgSearchTypeAlternatives = null;
 
diff --git a/includes/ServiceWiring.php b/includes/ServiceWiring.php
index 9071418e1817..62998d395c5c 100644
--- a/includes/ServiceWiring.php
+++ b/includes/ServiceWiring.php
@@ -969,8 +969,11 @@ return [
 	'SearchEngineConfig' => function ( MediaWikiServices $services ) : SearchEngineConfig {
 		// @todo This should not take a Config object, but it's not so easy to remove because it
 		// exposes it in a getter, which is actually used.
-		return new SearchEngineConfig( $services->getMainConfig(),
-			$services->getContentLanguage() );
+		return new SearchEngineConfig(
+			$services->getMainConfig(),
+			$services->getContentLanguage(),
+			ExtensionRegistry::getInstance()->getAttribute( 'SearchMappings' )
+		);
 	},
 
 	'SearchEngineFactory' => function ( MediaWikiServices $services ) : SearchEngineFactory {
diff --git a/includes/registration/ExtensionProcessor.php b/includes/registration/ExtensionProcessor.php
index ea8ea216fef2..36dc32806084 100644
--- a/includes/registration/ExtensionProcessor.php
+++ b/includes/registration/ExtensionProcessor.php
@@ -131,6 +131,7 @@ class ExtensionProcessor implements Processor {
 		'type',
 		'config',
 		'config_prefix',
+		'SearchMappings',
 		'ServiceWiringFiles',
 		'ParserTestFiles',
 		'AutoloadClasses',
diff --git a/includes/search/SearchEngineConfig.php b/includes/search/SearchEngineConfig.php
index d79028c7b997..507006288a81 100644
--- a/includes/search/SearchEngineConfig.php
+++ b/includes/search/SearchEngineConfig.php
@@ -20,9 +20,20 @@ class SearchEngineConfig {
 	 */
 	private $language;
 
-	public function __construct( Config $config, Language $lang ) {
+	/**
+	 * Search Engine Mappings
+	 *
+	 * Key is the canonical name (used in $wgSearchType and $wgSearchTypeAlternatives).
+	 * Value is a specification for ObjectFactory.
+	 *
+	 * @var array
+	 */
+	private $engineMappings;
+
+	public function __construct( Config $config, Language $lang, array $mappings ) {
 		$this->config = $config;
 		$this->language = $lang;
+		$this->engineMappings = $mappings;
 	}
 
 	/**
@@ -100,6 +111,30 @@ class SearchEngineConfig {
 	}
 
 	/**
+	 * Returns the mappings between canonical search name and underlying PHP class
+	 *
+	 * Key is the canonical name (used in $wgSearchType and $wgSearchTypeAlternatives).
+	 * Value is a specification for ObjectFactory.
+	 *
+	 * For example to be able to use 'foobarsearch' in $wgSearchType and
+	 * $wgSearchTypeAlternatives but the PHP class for 'foobarsearch'
+	 * is 'MediaWiki\Extensions\FoobarSearch\FoobarSearch' set:
+	 *
+	 * @par extension.json Example:
+	 * @code
+	 * 'SearchMappings': {
+	 * 	'foobarsearch': { 'class': 'MediaWiki\\Extensions\\FoobarSearch\\FoobarSearch' }
+	 * }
+	 * @endcode
+	 *
+	 * @since 1.35
+	 * @return array
+	 */
+	public function getSearchMappings() {
+		return $this->engineMappings;
+	}
+
+	/**
 	 * Get a list of namespace names useful for showing in tooltips
 	 * and preferences.
 	 *
diff --git a/includes/search/SearchEngineFactory.php b/includes/search/SearchEngineFactory.php
index bd53fc6b1e21..2e3223809313 100644
--- a/includes/search/SearchEngineFactory.php
+++ b/includes/search/SearchEngineFactory.php
@@ -1,6 +1,7 @@
 <?php
 
 use MediaWiki\MediaWikiServices;
+use Wikimedia\ObjectFactory;
 use Wikimedia\Rdbms\IDatabase;
 use Wikimedia\Rdbms\ILoadBalancer;
 
@@ -21,6 +22,7 @@ class SearchEngineFactory {
 
 	/**
 	 * Create SearchEngine of the given type.
+	 *
 	 * @param string|null $type
 	 * @return SearchEngine
 	 */
@@ -37,11 +39,22 @@ class SearchEngineFactory {
 			$class = self::getSearchEngineClass( $lb );
 		}
 
-		if ( is_subclass_of( $class, SearchDatabase::class ) ) {
-			return new $class( $lb );
+		$mappings = $this->config->getSearchMappings();
+
+		if ( isset( $mappings[$class] ) ) {
+			$spec = $mappings[$class];
 		} else {
-			return new $class();
+			// Convert non mapped classes to ObjectFactory spec
+			$spec = [ 'class' => $class ];
 		}
+
+		$args = [];
+
+		if ( isset( $spec['class'] ) && is_subclass_of( $spec['class'], SearchDatabase::class ) ) {
+			$args['extraArgs'][] = $lb;
+		}
+
+		return ObjectFactory::getObjectFromSpec( $spec, $args );
 	}
 
 	/**
diff --git a/tests/phpunit/unit/includes/Rest/Handler/SearchHandlerTest.php b/tests/phpunit/unit/includes/Rest/Handler/SearchHandlerTest.php
index cc690e6ef810..865e7b63bda5 100644
--- a/tests/phpunit/unit/includes/Rest/Handler/SearchHandlerTest.php
+++ b/tests/phpunit/unit/includes/Rest/Handler/SearchHandlerTest.php
@@ -56,7 +56,7 @@ class SearchHandlerTest extends \MediaWikiUnitTestCase {
 
 		/** @var Language|MockObject $language */
 		$language = $this->createNoOpMock( Language::class );
-		$searchEngineConfig = new \SearchEngineConfig( $config, $language );
+		$searchEngineConfig = new \SearchEngineConfig( $config, $language, [] );
 
 		/** @var PermissionManager|MockObject $permissionManager */
 		$permissionManager = $this->createNoOpMock(