Automatic topic subscriptions (on any edit)

Bug: T284836
Change-Id: Ia42ad087218fd91a0cdd1664157d1049738e3c01

extension.json

@@ -497,6 +497,7 @@
 		"discussiontools-replytool": 1,
 		"discussiontools-sourcemodetoolbar": 1,
 		"discussiontools-topicsubscription": 1,
+		"discussiontools-autotopicsub": 1,
 		"discussiontools-abtest": ""
 	},
 	"config": {
@@ -532,6 +533,10 @@
 			"value": "default",
 			"description": "Override availability of DiscussionTools topic subscription feature. 'default', 'available', or 'unavailable'."
 		},
+		"DiscussionTools_autotopicsub": {
+			"value": "default",
+			"description": "Override availability of DiscussionTools automatic topic subscription feature. 'default', 'available', or 'unavailable'."
+		},
 		"DiscussionToolsEnableTopicSubscriptionBackend": {
 			"value": true,
 			"description": "Enable the topic subscription backend. This controls whether the feature can be tried out using the query parameter, and whether the Echo events will be created. Do not enable this unless the database tables exist. Do enable it before making the 'topicsubscription' feature available."

includes/Hooks/HookUtils.php

@@ -23,6 +23,8 @@ class HookUtils {
 	public const NEWTOPICTOOL = 'newtopictool';
 	public const SOURCEMODETOOLBAR = 'sourcemodetoolbar';
 	public const TOPICSUBSCRIPTION = 'topicsubscription';
+	public const AUTOTOPICSUB = 'autotopicsub';
+
 	/**
 	 * @var string[] List of all sub-features. Will be used to generate:
 	 *  - Feature override global: $wgDiscussionTools_FEATURE
@@ -34,6 +36,7 @@ class HookUtils {
 		self::NEWTOPICTOOL,
 		self::SOURCEMODETOOLBAR,
 		self::TOPICSUBSCRIPTION,
+		self::AUTOTOPICSUB,
 	];
 
 	/**
@@ -52,7 +55,7 @@ class HookUtils {
 			return false;
 		}
 
-		if ( $feature === self::TOPICSUBSCRIPTION && !$user->isRegistered() ) {
+		if ( ( $feature === self::TOPICSUBSCRIPTION || $feature === self::AUTOTOPICSUB ) && !$user->isRegistered() ) {
 			// Users must be logged in to use topic subscription
 			return false;
 		}
@@ -229,7 +232,10 @@ class HookUtils {
 
 		// Topic subscription is not available on your own talk page, as you will
 		// get 'edit-user-talk' notifications already. (T276996)
-		if ( $feature === self::TOPICSUBSCRIPTION && $title->equals( $output->getUser()->getTalkPage() ) ) {
+		if (
+			( $feature === self::TOPICSUBSCRIPTION || $feature === self::AUTOTOPICSUB ) &&
+			$title->equals( $output->getUser()->getTalkPage() )
+		) {
 			return false;
 		}
 
@@ -250,7 +256,7 @@ class HookUtils {
 			RequestContext::getMain()->getRequest()->getRawVal( 'dtenable' );
 
 		if (
-			$feature === self::TOPICSUBSCRIPTION &&
+			( $feature === self::TOPICSUBSCRIPTION || $feature === self::AUTOTOPICSUB ) &&
 			!$dtConfig->get( 'DiscussionToolsEnableTopicSubscriptionBackend' )
 		) {
 			// Can't be enabled via query, because the tables may not exist yet (T280082)
@@ -328,4 +334,27 @@ class HookUtils {
 			self::isFeatureEnabledForOutput( $out, self::NEWTOPICTOOL )
 		);
 	}
+
+	/**
+	 * Check if we should be adding automatic topic subscriptions for this user on this page.
+	 *
+	 * @param UserIdentity $user
+	 * @param Title $title
+	 * @return bool
+	 */
+	public static function shouldAddAutoSubscription( UserIdentity $user, Title $title ): bool {
+		// This duplicates the logic from isFeatureEnabledForOutput(),
+		// because we don't have access to the request or the output here.
+
+		// Topic subscription is not available on your own talk page, as you will
+		// get 'edit-user-talk' notifications already. (T276996)
+		// (can't use User::getTalkPage() to check because this is a UserIdentity)
+		if ( $title->inNamespace( NS_USER_TALK ) && $title->getText() === $user->getName() ) {
+			return false;
+		}
+
+		// Check if the user has automatic subscriptions enabled, and the tools are enabled on the page.
+		return static::isAvailableForTitle( $title ) &&
+			static::isFeatureEnabledForUser( $user, self::AUTOTOPICSUB );
+	}
 }

includes/Hooks/PreferenceHooks.php

@@ -95,6 +95,13 @@ class PreferenceHooks implements
 			];
 		}
 
+		if ( isset( $preferences['discussiontools-' . HookUtils::AUTOTOPICSUB] ) ) {
+			// Hide automatic subscriptions when subscriptions are disabled
+			$preferences['discussiontools-' . HookUtils::AUTOTOPICSUB]['hide-if'] = [
+				'===', 'discussiontools-' . HookUtils::TOPICSUBSCRIPTION, ''
+			];
+		}
+
 		$preferences['discussiontools-showadvanced'] = [
 			'type' => 'api',
 		];

includes/Notifications/EventDispatcher.php

@@ -266,6 +266,9 @@ class EventDispatcher {
 				],
 				'agent' => $user,
 			];
+
+			$titleForSubscriptions = Title::castFromPageIdentity( $title )->createFragmentTarget( $heading->getText() );
+			static::addAutoSubscription( $user, $titleForSubscriptions, $heading->getName() );
 		}
 	}
 
@@ -282,6 +285,26 @@ class EventDispatcher {
 		} );
 	}
 
+	/**
+	 * Add an automatic subscription to the given item, assuming the user has automatic subscriptions
+	 * enabled.
+	 *
+	 * @param UserIdentity $user
+	 * @param Title $title
+	 * @param string $itemName
+	 */
+	protected static function addAutoSubscription( UserIdentity $user, Title $title, string $itemName ) {
+		$dtConfig = MediaWikiServices::getInstance()->getConfigFactory()->makeConfig( 'discussiontools' );
+
+		if (
+			$dtConfig->get( 'DiscussionToolsEnableTopicSubscriptionBackend' ) &&
+			HookUtils::shouldAddAutoSubscription( $user, $title )
+		) {
+			$subscriptionStore = MediaWikiServices::getInstance()->getService( 'DiscussionTools.SubscriptionStore' );
+			$subscriptionStore->addAutoSubscriptionForUser( $user, $title, $itemName );
+		}
+	}
+
 	/**
 	 * Return all users subscribed to a comment
 	 *
@@ -295,7 +318,7 @@ class EventDispatcher {
 		$subscriptionStore = MediaWikiServices::getInstance()->getService( 'DiscussionTools.SubscriptionStore' );
 		$subscriptionItems = $subscriptionStore->getSubscriptionItemsForTopic(
 			$commentName,
-			SubscriptionStore::STATE_SUBSCRIBED
+			[ SubscriptionStore::STATE_SUBSCRIBED, SubscriptionStore::STATE_AUTOSUBSCRIBED ]
 		);
 
 		// Update notified timestamps

includes/SubscriptionStore.php

@@ -26,6 +26,7 @@ class SubscriptionStore {
 	 */
 	public const STATE_UNSUBSCRIBED = 0;
 	public const STATE_SUBSCRIBED = 1;
+	public const STATE_AUTOSUBSCRIBED = 2;
 
 	/** @var ILBFactory */
 	private $lbFactory;
@@ -69,14 +70,14 @@ class SubscriptionStore {
 	 * @param IDatabase $db
 	 * @param UserIdentity|null $user
 	 * @param array|null $itemNames
-	 * @param int|null $state One of SubscriptionStore::STATE_* constants
+	 * @param int|int[]|null $state One of (or an array of) SubscriptionStore::STATE_* constants
 	 * @return IResultWrapper|false
 	 */
 	private function fetchSubscriptions(
 		IDatabase $db,
 		?UserIdentity $user = null,
 		?array $itemNames = null,
-		?int $state = null
+		$state = null
 	) {
 		$conditions = [];
 
@@ -111,14 +112,14 @@ class SubscriptionStore {
 	/**
 	 * @param UserIdentity $user
 	 * @param array|null $itemNames
-	 * @param int|null $state One of SubscriptionStore::STATE_* constants
+	 * @param int[]|null $state Array of SubscriptionStore::STATE_* constants
 	 * @param array $options
 	 * @return SubscriptionItem[]
 	 */
 	public function getSubscriptionItemsForUser(
 		UserIdentity $user,
 		?array $itemNames = null,
-		?int $state = null,
+		?array $state = null,
 		array $options = []
 	): array {
 		// Only a registered user can be subscribed
@@ -151,13 +152,13 @@ class SubscriptionStore {
 
 	/**
 	 * @param string $itemName
-	 * @param int|null $state One of SubscriptionStore::STATE_* constants
+	 * @param int[]|null $state An array of SubscriptionStore::STATE_* constants
 	 * @param array $options
 	 * @return array
 	 */
 	public function getSubscriptionItemsForTopic(
 		string $itemName,
-		?int $state = null,
+		?array $state = null,
 		array $options = []
 	): array {
 		$options += [ 'forWrite' => false ];
@@ -239,12 +240,14 @@ class SubscriptionStore {
 	 * @param UserIdentity $user
 	 * @param LinkTarget $target
 	 * @param string $itemName
+	 * @param int $state
 	 * @return bool
 	 */
 	public function addSubscriptionForUser(
 		UserIdentity $user,
 		LinkTarget $target,
-		string $itemName
+		string $itemName,
+		int $state = self::STATE_SUBSCRIBED
 	): bool {
 		if ( $this->readOnlyMode->isReadOnly() ) {
 			return false;
@@ -265,12 +268,12 @@ class SubscriptionStore {
 				'sub_title' => $target->getDBkey(),
 				'sub_section' => $target->getFragment(),
 				'sub_item' => $itemName,
-				'sub_state' => self::STATE_SUBSCRIBED,
+				'sub_state' => $state,
 				'sub_created' => $dbw->timestamp(),
 			],
 			[ [ 'sub_user', 'sub_item' ] ],
 			[
-				'sub_state' => self::STATE_SUBSCRIBED,
+				'sub_state' => $state,
 			],
 			__METHOD__
 		);
@@ -306,6 +309,37 @@ class SubscriptionStore {
 		return (bool)$dbw->affectedRows();
 	}
 
+	/**
+	 * @param UserIdentity $user
+	 * @param LinkTarget $target
+	 * @param string $itemName
+	 * @return bool
+	 */
+	public function addAutoSubscriptionForUser(
+		UserIdentity $user,
+		LinkTarget $target,
+		string $itemName
+	): bool {
+		// Check for existing subscriptions.
+		// Note that this includes subscriptions with state=STATE_UNSUBSCRIBED.
+		$subscriptionItems = $this->getSubscriptionItemsForUser(
+			$user,
+			[ $itemName ],
+			null,
+			[ 'forWrite' => true ]
+		);
+		if ( $subscriptionItems ) {
+			return false;
+		}
+
+		return $this->addSubscriptionForUser(
+			$user,
+			$target,
+			$itemName,
+			self::STATE_AUTOSUBSCRIBED
+		);
+	}
+
 	/**
 	 * @param string $field Timestamp field name
 	 * @param UserIdentity|null $user

sql/discussiontools_subscription.json

@@ -49,7 +49,7 @@
 			},
 			{
 				"name": "sub_state",
-				"comment": "0: unsubscribed; 1: subscribed",
+				"comment": "0: unsubscribed; 1: subscribed, 2: auto-subscribed",
 				"type": "integer",
 				"options": {
 					"notnull": true,

tests/phpunit/MockEventDispatcher.php

@@ -7,6 +7,7 @@ use MediaWiki\Extension\DiscussionTools\Notifications\EventDispatcher;
 use MediaWiki\Page\PageIdentity;
 use MediaWiki\Revision\RevisionRecord;
 use MediaWiki\User\UserIdentity;
+use Title;
 
 class MockEventDispatcher extends EventDispatcher {
 
@@ -50,4 +51,14 @@ class MockEventDispatcher extends EventDispatcher {
 	public static function addCommentChangeTag( RevisionRecord $newRevRecord ) {
 	}
 
+	/**
+	 * No-op for testing
+	 *
+	 * @param UserIdentity $user
+	 * @param Title $title
+	 * @param string $itemName
+	 */
+	protected static function addAutoSubscription( UserIdentity $user, Title $title, string $itemName ) {
+	}
+
 }

tests/phpunit/MockSubscriptionStore.php

@@ -16,14 +16,14 @@ class MockSubscriptionStore extends SubscriptionStore {
 	/**
 	 * @param UserIdentity $user Unused, required for inheritance
 	 * @param array|null $itemNames Unused, required for inheritance
-	 * @param int|null $state Unused, required for inheritance
+	 * @param int[]|null $state Unused, required for inheritance
 	 * @param array $options Unused, required for inheritance
-	 * @return array
+	 * @return SubscriptionItem[]
 	 */
 	public function getSubscriptionItemsForUser(
 		UserIdentity $user,
 		?array $itemNames = null,
-		?int $state = null,
+		?array $state = null,
 		array $options = []
 	): array {
 		return [];