Add support for quote reactions and improve quote detection (#2330)

Author: pfefferle

.github/changelog/2330-from-description

@@ -0,0 +1,4 @@
+Significance: minor
+Type: added
+
+Added support for quote comments, improving detection and handling of quoted replies and links in post interactions.

includes/activity/class-base-object.php

@@ -46,6 +46,10 @@
  * @method string[]|null        get_name_map()           Gets the name map property of the object.
  * @method string|null          get_preview()            Gets the entity that provides a preview of this object.
  * @method string|null          get_published()          Gets the date and time the object was published in ISO 8601 format.
+ * @method string|null          get_quote()              Gets the quote property of the object (FEP-044f).
+ * @method string|null          get_quote_url()          Gets the quoteUrl property of the object.
+ * @method string|null          get_quote_uri()          Gets the quoteUri property of the object.
+ * @method string|null          get__misskey_quote()     Gets the _misskey_quote property of the object.
  * @method string|array|null    get_replies()            Gets the collection of responses to this object.
  * @method bool|null            get_sensitive()          Gets the sensitive property of the object.
  * @method array|null           get_shares()             Gets the collection of shares for this object.
@@ -87,6 +91,10 @@
  * @method Base_Object set_name_map( array|null $name_map )            Sets the name map property of the object.
  * @method Base_Object set_preview( string $preview )                  Sets the entity that provides a preview of this object.
  * @method Base_Object set_published( string|null $published )         Sets the date and time the object was published in ISO 8601 format.
+ * @method Base_Object set_quote( string $quote )                      Sets the quote property of the object (FEP-044f).
+ * @method Base_Object set_quote_url( string $quote_url )              Sets the quoteUrl property of the object.
+ * @method Base_Object set_quote_uri( string $quote_uri )              Sets the quoteUri property of the object.
+ * @method Base_Object set__misskey_quote( mixed $misskey_quote )      Sets the _misskey_quote property of the object.
  * @method Base_Object set_replies( string|array $replies )            Sets the collection of responses to this object.
  * @method Base_Object set_sensitive( bool|null $sensitive )           Sets the sensitive property of the object.
  * @method Base_Object set_shares( array $shares )                     Sets the collection of shares for this object.
@@ -552,6 +560,43 @@ class Base_Object extends Generic_Object {
 	 */
 	protected $interaction_policy;
 
+	/**
+	 * Fediverse Enhancement Proposal 044f: Quote Property
+	 *
+	 * @see https://codeberg.org/fediverse/fep/src/branch/main/fep/044f/fep-044f.md
+	 * @see https://w3id.org/fep/044f#quote
+	 *
+	 * @var string|null
+	 */
+	protected $quote;
+
+	/**
+	 * ActivityStreams quoteUrl property.
+	 *
+	 * @see https://www.w3.org/ns/activitystreams#quoteUrl
+	 *
+	 * @var string|null
+	 */
+	protected $quote_url;
+
+	/**
+	 * Fedibird-specific quoteUri property.
+	 *
+	 * @see https://fedibird.com/ns#quoteUri
+	 *
+	 * @var string|null
+	 */
+	protected $quote_uri;
+
+	/**
+	 * Misskey-specific quote property.
+	 *
+	 * @see https://misskey-hub.net/ns/#_misskey_quote
+	 *
+	 * @var string|null
+	 */
+	protected $_misskey_quote; // phpcs:ignore PSR2.Classes.PropertyDeclaration.Underscore
+
 	/**
 	 * Generic getter.
 	 *

includes/activity/class-generic-object.php

@@ -204,7 +204,11 @@ public static function init_from_array( $data ) {
 	public function from_array( $data ) {
 		foreach ( $data as $key => $value ) {
 			if ( null !== $value ) {
-				$key = camel_to_snake_case( $key );
+				// Convert camelCase to snake_case if not prefixed with '_'.
+				if ( ! \str_starts_with( $key, '_' ) ) {
+					$key = camel_to_snake_case( $key );
+				}
+
 				call_user_func( array( $this, 'set_' . $key ), $value );
 			}
 		}

includes/class-comment.php

@@ -610,7 +610,7 @@ public static function register_comment_types() {
 			array(
 				'label'          => __( 'Reposts', 'activitypub' ),
 				'singular'       => __( 'Repost', 'activitypub' ),
-				'description'    => __( 'A repost on the indieweb is a post that is purely a 100% re-publication of another (typically someone else\'s) post.', 'activitypub' ),
+				'description'    => 'A repost (or Announce) is when a post appears in the timeline because someone else shared it, while still showing the original author as the source.',
 				'icon'           => '♻️',
 				'class'          => 'p-repost',
 				'type'           => 'repost',
@@ -629,7 +629,7 @@ public static function register_comment_types() {
 			array(
 				'label'          => __( 'Likes', 'activitypub' ),
 				'singular'       => __( 'Like', 'activitypub' ),
-				'description'    => __( 'A like is a popular webaction button and in some cases post type on various silos such as Facebook and Instagram.', 'activitypub' ),
+				'description'    => 'A like is a small positive reaction that shows appreciation for a post without sharing it further.',
 				'icon'           => '👍',
 				'class'          => 'p-like',
 				'type'           => 'like',
@@ -642,6 +642,25 @@ public static function register_comment_types() {
 				'count_plural'   => _x( '%d likes', 'number of likes', 'activitypub' ),
 			)
 		);
+
+		register_comment_type(
+			'quote',
+			array(
+				'label'          => __( 'Quotes', 'activitypub' ),
+				'singular'       => __( 'Quote', 'activitypub' ),
+				'description'    => 'A quote is when a post is shared along with an added comment, so the original post appears together with the sharer’s own words.',
+				'icon'           => '❞',
+				'class'          => 'p-quote',
+				'type'           => 'quote',
+				'collection'     => 'quotes',
+				'activity_types' => array( 'quote' ),
+				'excerpt'        => html_entity_decode( \__( '… quoted this!', 'activitypub' ) ),
+				/* translators: %d: Number of quotes */
+				'count_single'   => _x( '%d quote', 'number of quotes', 'activitypub' ),
+				/* translators: %d: Number of quotes */
+				'count_plural'   => _x( '%d quotes', 'number of quotes', 'activitypub' ),
+			)
+		);
 	}
 
 	/**

includes/collection/class-interactions.php

@@ -34,18 +34,42 @@ class Interactions {
 	public static function add_comment( $activity ) {
 		$comment_data = self::activity_to_comment( $activity );
 
-		if ( ! $comment_data || ! isset( $activity['object']['inReplyTo'] ) ) {
+		if ( ! $comment_data ) {
 			return false;
 		}
 
-		$in_reply_to       = object_to_uri( $activity['object']['inReplyTo'] );
-		$in_reply_to       = \esc_url_raw( $in_reply_to );
-		$comment_post_id   = \url_to_postid( $in_reply_to );
-		$parent_comment_id = url_to_commentid( $in_reply_to );
+		// Determine target URL from reply or quote.
+		$parent_comment_id = 0;
+
+		if ( ! empty( $activity['object']['inReplyTo'] ) ) {
+			// Regular reply.
+			$target_url        = object_to_uri( $activity['object']['inReplyTo'] );
+			$parent_comment_id = url_to_commentid( $target_url );
+		} else {
+			// Check for quote.
+			$target_url = self::get_quote_url( $activity );
 
-		// Save only replies and reactions.
+			if ( ! $target_url ) {
+				return false;
+			}
+
+			// Mark as quote and clean content.
+			$comment_data['comment_type'] = 'quote';
+
+			if ( ! empty( $activity['object']['content'] ) ) {
+				$pattern                         = '/<p[^>]*class=["\']quote-inline["\'][^>]*>.*?<\/p>/is';
+				$cleaned_content                 = \preg_replace( $pattern, '', $activity['object']['content'], 1 );
+				$comment_data['comment_content'] = \wp_kses_post( $cleaned_content );
+			}
+		}
+
+		// Get post ID from target URL.
+		$target_url      = \esc_url_raw( $target_url );
+		$comment_post_id = \url_to_postid( $target_url );
+
+		// Handle nested replies (replies to comments).
 		if ( ! $comment_post_id && $parent_comment_id ) {
-			$parent_comment  = get_comment( $parent_comment_id );
+			$parent_comment  = \get_comment( $parent_comment_id );
 			$comment_post_id = $parent_comment->comment_post_ID;
 		}
 
@@ -411,4 +435,33 @@ public static function count_by_type( $post_id, $type ) {
 			)
 		);
 	}
+
+	/**
+	 * Get the quote URL from an activity.
+	 *
+	 * Checks for quote properties in priority order: quote -> quoteUrl -> quoteUri -> _misskey_quote.
+	 *
+	 * @param array $activity The activity array.
+	 *
+	 * @return string|false The quote URL or false if not found.
+	 */
+	public static function get_quote_url( $activity ) {
+		if ( ! empty( $activity['object']['quote'] ) ) {
+			return object_to_uri( $activity['object']['quote'] );
+		}
+
+		if ( ! empty( $activity['object']['quoteUrl'] ) ) {
+			return object_to_uri( $activity['object']['quoteUrl'] );
+		}
+
+		if ( ! empty( $activity['object']['quoteUri'] ) ) {
+			return object_to_uri( $activity['object']['quoteUri'] );
+		}
+
+		if ( ! empty( $activity['object']['_misskey_quote'] ) ) {
+			return object_to_uri( $activity['object']['_misskey_quote'] );
+		}
+
+		return false;
+	}
 }

includes/functions.php

@@ -631,6 +631,22 @@ function is_activity_reply( $data ) {
 	return ! empty( $data['object']['inReplyTo'] );
 }
 
+/**
+ * Check if passed Activity is a quote.
+ *
+ * Checks for quote properties: quote, quoteUrl, quoteUri, or _misskey_quote.
+ *
+ * @param array $data The Activity object as array.
+ *
+ * @return boolean True if a quote, false if not.
+ */
+function is_quote_activity( $data ) {
+	return ! empty( $data['object']['quote'] ) ||
+		! empty( $data['object']['quoteUrl'] ) ||
+		! empty( $data['object']['quoteUri'] ) ||
+		! empty( $data['object']['_misskey_quote'] );
+}
+
 /**
  * Get active users based on a given duration.
  *

includes/handler/class-create.php

@@ -12,6 +12,7 @@
 
 use function Activitypub\get_activity_visibility;
 use function Activitypub\is_activity_reply;
+use function Activitypub\is_quote_activity;
 use function Activitypub\is_self_ping;
 use function Activitypub\object_id_to_comment;
 
@@ -38,7 +39,7 @@ public static function handle_create( $activity, $user_ids, $activity_object = n
 		// Check for private and/or direct messages.
 		if ( ACTIVITYPUB_CONTENT_VISIBILITY_PRIVATE === get_activity_visibility( $activity ) ) {
 			$result = false;
-		} elseif ( is_activity_reply( $activity ) ) { // Check for replies.
+		} elseif ( is_activity_reply( $activity ) || is_quote_activity( $activity ) ) { // Check for replies and quotes.
 			$result = self::create_interaction( $activity, $user_ids, $activity_object );
 		} elseif ( \get_option( 'activitypub_create_posts', false ) ) { // Handle non-interaction objects.
 			$result = self::create_post( $activity, $user_ids, $activity_object );

integration/class-jetpack.php

@@ -77,8 +77,9 @@ public static function add_sync_comment_meta( $allow_list ) {
 	 * @return array The comment types with ActivityPub types added.
 	 */
 	public static function add_comment_types( $comment_types ) {
-		$comment_types[] = 'repost';
 		$comment_types[] = 'like';
+		$comment_types[] = 'quote';
+		$comment_types[] = 'repost';
 
 		return array_unique( $comment_types );
 	}

tests/phpunit/tests/includes/activity/class-test-generic-object.php

@@ -5,8 +5,10 @@
  * @package Activitypub
  */
 
-namespace Activitypub\Activity;
+namespace Activitypub\Tests\Activity;
 
+use Activitypub\Activity\Base_Object;
+use Activitypub\Activity\Generic_Object;
 use WP_UnitTestCase;
 
 /**
@@ -117,4 +119,79 @@ public function test_to_array() {
 		$this->assertEquals( $test_data['inReplyTo'], $array['inReplyTo'] );
 		$this->assertEquals( $test_data['mediaType'], $array['mediaType'] );
 	}
+
+	/**
+	 * Test if init_from_array correctly handles quote property.
+	 *
+	 * Tests that the quote property can be set from array.
+	 * Uses Base_Object which has the quote property defined.
+	 *
+	 * @covers Activitypub\Activity\Generic_Object::init_from_array
+	 */
+	public function test_init_from_array_quote_property() {
+		$test_data = array(
+			'id'    => 'https://example.com/note/123',
+			'type'  => 'Note',
+			'quote' => 'https://example.com/post/456',
+		);
+
+		$object = Base_Object::init_from_array( $test_data );
+
+		// Verify quote property is accessible.
+		$this->assertEquals( $test_data['quote'], $object->get_quote() );
+	}
+
+	/**
+	 * Test if init_from_array correctly handles underscore-prefixed properties.
+	 *
+	 * Uses Base_Object which has the _misskey_quote property defined.
+	 *
+	 * @covers Activitypub\Activity\Generic_Object::init_from_array
+	 */
+	public function test_init_from_array_underscore_properties() {
+		$test_data = array(
+			'id'             => 'https://example.com/note/123',
+			'type'           => 'Note',
+			'_misskey_quote' => 'https://example.com/post/789',
+		);
+
+		$object = Base_Object::init_from_array( $test_data );
+
+		// Test that underscore property is accessible.
+		$this->assertEquals( $test_data['_misskey_quote'], $object->get__misskey_quote() );
+	}
+
+	/**
+	 * Test quote properties round-trip through set/get.
+	 *
+	 * Uses Base_Object to verify quote properties can be set and retrieved.
+	 *
+	 * @covers Activitypub\Activity\Generic_Object::__call
+	 */
+	public function test_quote_properties_set_and_get() {
+		$object = new Base_Object();
+
+		$object->set_quote( 'https://example.com/post/456' );
+		$object->set_quote_url( 'https://example.com/post/789' );
+		$object->set_quote_uri( 'https://example.com/post/101' );
+
+		$this->assertEquals( 'https://example.com/post/456', $object->get_quote() );
+		$this->assertEquals( 'https://example.com/post/789', $object->get_quote_url() );
+		$this->assertEquals( 'https://example.com/post/101', $object->get_quote_uri() );
+	}
+
+	/**
+	 * Test underscore-prefixed properties round-trip through set/get.
+	 *
+	 * Uses Base_Object to verify _misskey_quote property can be set and retrieved.
+	 *
+	 * @covers Activitypub\Activity\Generic_Object::__call
+	 */
+	public function test_underscore_properties_set_and_get() {
+		$object = new Base_Object();
+
+		$object->set__misskey_quote( 'https://example.com/post/789' );
+
+		$this->assertEquals( 'https://example.com/post/789', $object->get__misskey_quote() );
+	}
 }