Fixes PHP warnings and remote delete (#468)

* fix #463

* fix delete

/cc #465 @janboddez

* add disclaimer to not use the same name as an author login

see #470

* check if url is cached before trashing it

includes/class-signature.php

@@ -240,8 +240,11 @@ class Signature {
 			}
 
 			// fix route for subdirectory installs
-			$path = wp_parse_url( get_home_url(), PHP_URL_PATH );
+			$path = \wp_parse_url( \get_home_url(), PHP_URL_PATH );
+
+			if ( \is_string( $path ) ) {
 				$path = trim( $path, '/' );
+			}
 
 			if ( $path ) {
 				$route = '/' . $path . $route;

includes/transformer/class-post.php

@@ -115,8 +115,8 @@ class Post {
 		$wp_post = $this->wp_post;
 		$object = new Base_Object();
 
-		$object->set_id( \esc_url( \get_permalink( $wp_post->ID ) ) );
+		$object->set_id( $this->get_id() );
-		$object->set_url( \esc_url( \get_permalink( $wp_post->ID ) ) );
+		$object->set_url( $this->get_url() );
 		$object->set_type( $this->get_object_type() );
 
 		$published = \strtotime( $wp_post->post_date_gmt );
@@ -151,6 +151,32 @@ class Post {
 		return $object;
 	}
 
+	/**
+	 * Returns the ID of the Post.
+	 *
+	 * @return string The Posts ID.
+	 */
+	public function get_id() {
+		return $this->get_url();
+	}
+
+	/**
+	 * Returns the URL of the Post.
+	 *
+	 * @return string The Posts URL.
+	 */
+	public function get_url() {
+		$post = $this->wp_post;
+
+		if ( 'trash' === get_post_status( $post ) ) {
+			$permalink = \get_post_meta( $post->ID, 'activitypub_canonical_url', true );
+		} else {
+			$permalink = \get_permalink( $post );
+		}
+
+		return \esc_url( $permalink );
+	}
+
 	/**
 	 * Returns the User-URL of the Author of the Post.
 	 *

templates/settings.php

@@ -55,6 +55,11 @@
 							<p class="description">
 								<?php \esc_html_e( 'This profile name will federate all posts written on your blog, regardless of the author who posted it.', 'activitypub' ); ?>
 							</p>
+							<p>
+								<strong>
+									<?php \esc_html_e( 'Please avoid using an existing author’s name as the blog profile ID. Fediverse platforms might use caching and this could break the functionality completely.', 'activitypub' ); ?>
+								</strong>
+							</p>
 						</td>
 					</tr>
 				</tbody>

tests/test-class-activitypub-post.php

@@ -19,5 +19,9 @@ class Test_Activitypub_Post extends WP_UnitTestCase {
 		$activitypub_post = \Activitypub\Transformer\Post::transform( get_post( $post ) )->to_object();
 
 		$this->assertEquals( $permalink, $activitypub_post->get_id() );
+
+		$cached = \get_post_meta( $post, 'activitypub_canonical_url', true );
+
+		$this->assertEquals( $cached, $activitypub_post->get_id() );
 	}
 }