Add "Stream" Plugin support (#863)

* Add "Stream" Plugin support

This PR adds support for the Stream Plugin. It maps the Notifications to the Stream plugin, that might help us with debugging.

* send type specific notification action

...to be able to subscribe to only a certain type of notifications.

Author: pfefferle

includes/class-notification.php

@@ -53,6 +53,9 @@ public function __construct( $type, $actor, $object, $target ) { // phpcs:ignore
 	 * Send the notification.
 	 */
 	public function send() {
+		$type = \strtolower( $this->type );
+
 		do_action( 'activitypub_notification', $this );
+		do_action( "activitypub_notification_{$type}", $this );
 	}
 }

integration/class-stream-connector.php

@@ -0,0 +1,78 @@
+<?php
+namespace Activitypub\Integration;
+
+/**
+ * Stream Connector for ActivityPub
+ *
+ * This class is a Stream Connector for the Stream plugin.
+ *
+ * @see https://wordpress.org/plugins/stream/
+ */
+class Stream_Connector extends \WP_Stream\Connector {
+	/**
+	 * Connector slug
+	 *
+	 * @var string
+	 */
+	public $name = 'activitypub';
+
+	/**
+	 * Actions registered for this connector
+	 *
+	 * @var array
+	 */
+	public $actions = array(
+		'activitypub_notification_follow',
+	);
+
+	/**
+	 * Return translated connector label
+	 *
+	 * @return string
+	 */
+	public function get_label() {
+		return __( 'ActivityPub', 'activitypub' );
+	}
+
+	/**
+	 * Return translated context labels
+	 *
+	 * @return array
+	 */
+	public function get_context_labels() {
+		return array();
+	}
+
+	/**
+	 * Return translated action labels
+	 *
+	 * @return array
+	 */
+	public function get_action_labels() {
+		return array();
+	}
+
+	/**
+	 * Callback for activitypub_notification_follow
+	 *
+	 * @param \Activitypub\Notification $notification The notification object
+	 *
+	 * @return void
+	 */
+	public function callback_activitypub_notification_follow( $notification ) {
+		$this->log(
+			sprintf(
+				// translators: %s is a URL
+				__( 'New Follower: %s', 'activitypub' ),
+				$notification->actor
+			),
+			array(
+				'notification' => \wp_json_encode( $notification, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE ),
+			),
+			null,
+			'notification',
+			$notification->type,
+			$notification->target
+		);
+	}
+}

integration/load.php

@@ -90,6 +90,48 @@ function( $transformer, $object, $object_class ) {
 }
 \add_action( 'plugins_loaded', __NAMESPACE__ . '\plugin_init' );
 
+/**
+ * Register the Stream Connector for ActivityPub.
+ *
+ * @param array $classes The Stream connectors.
+ *
+ * @return array The Stream connectors with the ActivityPub connector.
+ */
+function register_stream_connector( $classes ) {
+	require plugin_dir_path( __FILE__ ) . '/class-stream-connector.php';
+
+	$class_name = '\Activitypub\Integration\Stream_Connector';
+
+	if ( ! class_exists( $class_name ) ) {
+		return;
+	}
+
+	wp_stream_get_instance();
+	$class = new $class_name();
+
+	if ( ! method_exists( $class, 'is_dependency_satisfied' ) ) {
+		return;
+	}
+
+	if ( $class->is_dependency_satisfied() ) {
+		$classes[] = $class;
+	}
+
+	return $classes;
+}
+add_filter( 'wp_stream_connectors', __NAMESPACE__ . '\register_stream_connector' );
+
+// Excluded ActivityPub post types from the Stream.
+add_filter(
+	'wp_stream_posts_exclude_post_types',
+	function( $post_types ) {
+		$post_types[] = 'ap_follower';
+		$post_types[] = 'ap_extrafield';
+		$post_types[] = 'ap_extrafield_blog';
+		return $post_types;
+	}
+);
+
 /**
  * Load the BuddyPress integration.
  *