Add metadata to New Follower E-Mail (#1172)

* Add metadata to New Follower E-Mail

* changelog

* Remove HTML escaping from subject and plain text

* Lint fixes

* update comment

* No need to HTML escape inside the plain text

* Resolve some PR feedbacks

* Use load_template to align with other uses

* Add footer link to follower list.

Props @pfefferle

* Move follower list into separate paragraph for better margins

* Clarify who this new follower is following

---------

Co-authored-by: Konstantin Obenland <[email protected]>
Co-authored-by: Matthias Pfefferle <[email protected]>

Author: 3 people

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 * Setting to adjust the number of days Outbox items are kept before being purged.
+* Metadata to New Follower E-Mail.
 
 ### Changed
 

includes/class-mailer.php

@@ -134,16 +134,35 @@ public static function new_follower( $notification ) {
 			$admin_url = '/users.php?page=activitypub-followers-list';
 		}
 
-		/* translators: 1: Blog name, 2: Follower name */
-		$subject = \sprintf( \esc_html__( '[%1$s] Follower: %2$s', 'activitypub' ), \esc_html( get_option( 'blogname' ) ), \esc_html( $actor['name'] ) );
-		/* translators: 1: Blog name, 2: Follower name */
-		$message = \sprintf( \esc_html__( 'New Follower: %2$s.', 'activitypub' ), \esc_html( get_option( 'blogname' ) ), \esc_html( $actor['name'] ) ) . "\r\n\r\n";
-		/* translators: Follower URL */
-		$message .= \sprintf( \esc_html__( 'URL: %s', 'activitypub' ), \esc_url( $actor['url'] ) ) . "\r\n\r\n";
-		$message .= \esc_html__( 'You can see all followers here:', 'activitypub' ) . "\r\n";
-		$message .= \esc_url( \admin_url( $admin_url ) ) . "\r\n\r\n";
+		$template_args = array_merge(
+			$actor,
+			array(
+				'admin_url' => $admin_url,
+				'target'    => $notification->target,
+			)
+		);
 
-		\wp_mail( $email, $subject, $message );
+		/* translators: 1: Blog name, 2: Follower name */
+		$subject = \sprintf( \__( '[%1$s] New Follower: %2$s', 'activitypub' ), get_option( 'blogname' ), $actor['name'] );
+
+		\ob_start();
+		\load_template( ACTIVITYPUB_PLUGIN_DIR . 'templates/new-follower-email.php', false, $template_args );
+		$html_message = \ob_get_clean();
+
+		$alt_function = function ( $mailer ) use ( $actor, $admin_url ) {
+			/* translators: 1: Follower name */
+			$message = \sprintf( \__( 'New Follower: %1$s.', 'activitypub' ), $actor['name'] ) . "\r\n\r\n";
+			/* translators: Follower URL */
+			$message            .= \sprintf( \__( 'URL: %s', 'activitypub' ), \esc_url( $actor['url'] ) ) . "\r\n\r\n";
+			$message            .= \__( 'You can see all followers here:', 'activitypub' ) . "\r\n";
+			$message            .= \esc_url( \admin_url( $admin_url ) ) . "\r\n\r\n";
+			$mailer->{'AltBody'} = $message;
+		};
+		\add_action( 'phpmailer_init', $alt_function );
+
+		\wp_mail( $email, $subject, $html_message, array( 'Content-type: text/html' ) );
+
+		\remove_action( 'phpmailer_init', $alt_function );
 	}
 
 	/**

readme.txt

@@ -134,6 +134,7 @@ For reasons of data protection, it is not possible to see the followers of other
 * Added: Allow Activities on URLs instead of requiring Activity-Objects. This is useful especially for sending Announces and Likes.
 * Added: Undo API for Outbox items.
 * Added: Setting to adjust the number of days Outbox items are kept before being purged.
+* Added: Show metadata in the New Follower E-Mail.
 * Changed: Outbox now precesses the first batch of followers right away to avoid delays in processing new Activities.
 * Fixed: The Outbox purging routine no longer is limited to deleting 5 items at a time.
 * Fixed an issue where the outbox could not send object types other than `Base_Object` (introduced in 5.0.0).

templates/new-follower-email.php

@@ -0,0 +1,63 @@
+<?php
+/**
+ * ActivityPub New Follower E-Mail template.
+ *
+ * @package Activitypub
+ */
+
+use Activitypub\Collection\Actors;
+
+/* @var array $args Template arguments. */
+$args = wp_parse_args( $args );
+?>
+<p>
+	<?php
+	if ( Actors::BLOG_USER_ID === $args['target'] ) :
+		esc_html_e( 'Your blog has a new follower:', 'activitypub' );
+	else :
+		esc_html_e( 'You have a new follower:', 'activitypub' );
+	endif;
+	?>
+</p>
+
+<table>
+	<tr>
+		<td style="vertical-align: top">
+			<a href="<?php echo esc_url( $args['url'] ); ?>" style="float: left; margin-right: 1em;">
+				<?php if ( ! empty( $args['icon']['url'] ) ) : ?>
+					<img src="<?php echo esc_url( $args['icon']['url'] ); ?>" alt="<?php echo esc_attr( $args['name'] ); ?>" width="64" height="64">
+				<?php endif; ?>
+			</a>
+		</td>
+		<td>
+			<a href="<?php echo esc_url( $args['url'] ); ?>">
+				<strong><?php echo esc_html( $args['name'] ); ?></strong> (<?php echo esc_html( $args['url'] ); ?>)
+			</a>
+			<br>
+			<?php
+			if ( ! empty( $args['summary'] ) ) :
+				echo wp_kses_post( nl2br( $args['summary'] ) );
+			endif;
+			?>
+		</td>
+	</tr>
+</table>
+
+<p>
+	<?php
+	printf(
+		/* translators: %s: URL to followers list. */
+		wp_kses( __( 'Visit the <a href="%s">followers list</a> to see all followers.', 'activitypub' ), array( 'a' => array( 'href' => array() ) ) ),
+		esc_url( admin_url( $args['admin_url'] ) )
+	);
+	?>
+</p>
+
+<?php
+
+/**
+ * Fires at the bottom of the new follower email.
+ *
+ * @param array $args The actor that followed the blog.
+ */
+do_action( 'activitypub_new_follower_email', $args );