AbuseFilterHooks: Provide feature flags for AF custom actions

Why:

- There are issues with the current "showcaptcha" action, and we need to
  disable it until the problems are fixed

What:

- Define a feature flag to enable custom actions. For now, nothing is
  enabled.

Bug: T20110
Change-Id: I3484d66298bc9f49dfbe003a0605e2ac1a092e10

extension.json

@@ -96,7 +96,10 @@
 			]
 		},
 		"AbuseFilterHooks": {
-			"class": "MediaWiki\\Extension\\ConfirmEdit\\AbuseFilterHooks"
+			"class": "MediaWiki\\Extension\\ConfirmEdit\\AbuseFilterHooks",
+			"services": [
+				"MainConfig"
+			]
 		}
 	},
 	"Hooks": {
@@ -170,6 +173,10 @@
 		},
 		"CaptchaRegexes": {
 			"value": []
+		},
+		"ConfirmEditEnabledAbuseFilterCustomActions": {
+			"description": "Feature flag to toggle list of available custom actions to enable in AbuseFilter. See AbuseFilterHooks::onAbuseFilterCustomActions",
+			"value": []
 		}
 	},
 	"manifest_version": 2

includes/AbuseFilterHooks.php

@@ -2,17 +2,27 @@
 
 namespace MediaWiki\Extension\ConfirmEdit;
 
+use MediaWiki\Config\Config;
 use MediaWiki\Extension\AbuseFilter\Consequences\Parameters;
 use MediaWiki\Extension\AbuseFilter\Hooks\AbuseFilterCustomActionsHook;
 use MediaWiki\Extension\ConfirmEdit\AbuseFilter\CaptchaConsequence;
 
 class AbuseFilterHooks implements AbuseFilterCustomActionsHook {
 
+	private Config $config;
+
+	public function __construct( Config $config ) {
+		$this->config = $config;
+	}
+
 	/** @inheritDoc */
 	public function onAbuseFilterCustomActions( array &$actions ): void {
-		$actions['showcaptcha'] = static function ( Parameters $params ): CaptchaConsequence {
-			return new CaptchaConsequence( $params );
-		};
+		$enabledActions = $this->config->get( 'ConfirmEditEnabledAbuseFilterCustomActions' );
+		if ( in_array( 'showcaptcha', $enabledActions ) ) {
+			$actions['showcaptcha'] = static function ( Parameters $params ): CaptchaConsequence {
+				return new CaptchaConsequence( $params );
+			};
+		}
 	}
 
 }

tests/phpunit/unit/AbuseFilterHooksTest.php

@@ -2,6 +2,7 @@
 
 namespace MediaWiki\Extension\ConfirmEdit\Test\Unit\AbuseFilter;
 
+use MediaWiki\Config\HashConfig;
 use MediaWiki\Extension\ConfirmEdit\AbuseFilterHooks;
 use MediaWikiUnitTestCase;
 
@@ -11,7 +12,8 @@ use MediaWikiUnitTestCase;
 class AbuseFilterHooksTest extends MediaWikiUnitTestCase {
 
 	public function testOnAbuseFilterCustomActions() {
-		$abuseFilterHooks = new AbuseFilterHooks();
+		$config = new HashConfig( [ 'ConfirmEditEnabledAbuseFilterCustomActions' => [ 'showcaptcha' ] ] );
+		$abuseFilterHooks = new AbuseFilterHooks( $config );
 		$actions = [];
 		$abuseFilterHooks->onAbuseFilterCustomActions( $actions );
 		$this->assertArrayHasKey( 'showcaptcha', $actions );