Simple Remote-Reply endpoint. (#866)

* Simple Remote-Comment endpoint.

implements #864

* move sanitize to args

* fix PHPDoc

* change from actions to filters

thanks @akirk for your feedback!

* add generic Interaction hook

Author: pfefferle

activitypub.php

@@ -62,6 +62,7 @@ function rest_init() {
 	Rest\Comment::init();
 	Rest\Server::init();
 	Rest\Collection::init();
+	Rest\Interaction::init();
 
 	// load NodeInfo endpoints only if blog is public
 	if ( is_blog_public() ) {

includes/rest/class-interaction.php

@@ -0,0 +1,103 @@
+<?php
+namespace Activitypub\Rest;
+
+use WP_REST_Response;
+use Activitypub\Http;
+
+class Interaction {
+	/**
+	 * Initialize the class, registering WordPress hooks
+	 */
+	public static function init() {
+		self::register_routes();
+	}
+
+	/**
+	 * Register routes
+	 */
+	public static function register_routes() {
+		\register_rest_route(
+			ACTIVITYPUB_REST_NAMESPACE,
+			'/interactions',
+			array(
+				array(
+					'methods'             => \WP_REST_Server::READABLE,
+					'callback'            => array( self::class, 'get' ),
+					'permission_callback' => '__return_true',
+					'args'                => array(
+						'uri' => array(
+							'type'              => 'string',
+							'required'          => true,
+							'sanitize_callback' => 'esc_url',
+						),
+					),
+				),
+			)
+		);
+	}
+
+	/**
+	 * Handle GET request
+	 *
+	 * @param WP_REST_Request $request The request object.
+	 *
+	 * @return wp_die|WP_REST_Response Redirect to the editor or die
+	 */
+	public static function get( $request ) {
+		$uri          = $request->get_param( 'uri' );
+		$redirect_url = null;
+		$object       = Http::get_remote_object( $uri );
+
+		if (
+			\is_wp_error( $object ) ||
+			! isset( $object['type'] )
+		) {
+			\wp_die(
+				\esc_html__(
+					'The URL is not supported!',
+					'activitypub'
+				),
+				400
+			);
+		}
+
+		if ( ! empty( $object['url'] ) ) {
+			$uri = \esc_url( $object['url'] );
+		}
+
+		switch ( $object['type'] ) {
+			case 'Group':
+			case 'Person':
+			case 'Service':
+			case 'Application':
+			case 'Organization':
+				$redirect_url = \apply_filters( 'activitypub_interactions_follow_url', $redirect_url, $uri, $object );
+				break;
+			default:
+				$redirect_url = \admin_url( 'post-new.php?in_reply_to=' . $uri );
+				$redirect_url = \apply_filters( 'activitypub_interactions_reply_url', $redirect_url, $uri, $object );
+		}
+
+		// generic Interaction hook
+		$redirect_url = \apply_filters( 'activitypub_interactions_url', $redirect_url, $uri, $object );
+
+		// check if hook is implemented
+		if ( ! $redirect_url ) {
+			\wp_die(
+				esc_html__(
+					'This Interaction type is not supported yet!',
+					'activitypub'
+				),
+				400
+			);
+		}
+
+		return new WP_REST_Response(
+			null,
+			302,
+			array(
+				'Location' => \esc_url( $redirect_url ),
+			)
+		);
+	}
+}

integration/class-webfinger.php

@@ -4,6 +4,8 @@
 use Activitypub\Rest\Webfinger as Webfinger_Rest;
 use Activitypub\Collection\Users as User_Collection;
 
+use function Activitypub\get_rest_url_by_path;
+
 /**
  * Compatibility with the WebFinger plugin
  *
@@ -45,6 +47,11 @@ public static function add_user_discovery( $array, $resource, $user ) {
 			'href' => $user->get_url(),
 		);
 
+		$array['links'][] = array(
+			'rel'      => 'http://ostatus.org/schema/1.0/subscribe',
+			'template' => get_rest_url_by_path( 'interactions?uri={uri}' ),
+		);
+
 		return $array;
 	}
 
@@ -85,6 +92,10 @@ public static function add_pseudo_user_discovery( $array, $resource ) {
 					'type' => 'text/html',
 					'href' => $user->get_url(),
 				),
+				array(
+					'rel'      => 'http://ostatus.org/schema/1.0/subscribe',
+					'template' => get_rest_url_by_path( 'interactions?uri={uri}' ),
+				),
 			),
 		);