Get the latest comments for a custom post type in WordPress

Custom post types for WordPress support comments, however the API doesn’t allow for retrieving those comments.

So in order to get the latest comments from your custom post type you need to do an sql query that does a LEFT OUTER JOIN between the comments table and the posts table:

/* Get recent comments */
global $wpdb;
				
$sql = "SELECT * FROM $wpdb->comments LEFT OUTER JOIN $wpdb->posts ON ($wpdb->comments.comment_post_ID = $wpdb->posts.ID) WHERE comment_approved = '1' AND comment_type = '' AND post_password = '' AND post_type='your_custom_post_type' ORDER BY comment_date_gmt DESC LIMIT 5";

$comments = $wpdb->get_results($sql);

foreach ($comments as $comment) {
  // we need the comment comment user_id in case it's a logged in user so we can echo the display name and not username
  if ($comment->user_id != 0) {
    $curent_userdata = get_userdata($comment->user_id);
    echo $curent_userdata->display_name;
  } else {
    echo strip_tags($comment->comment_author);
  }
 
  // the permalink for the comment
  echo get_permalink($comment->ID) . '#comment-' . $comment->comment_ID;

  // the post title where that comment was posted
  echo $comment->post_title; 
  
  // display the comment content
  echo strip_tags($comment->comment_content);
}

The important bit is in the SQL declaration:

post_type='your_custom_post_type' 

Let’s transform this into a widget

I’m not going to go through all the steps needed to create a widget for WordPress, instead I’ll just give you the code so you can use in your own projects.

 'cl_cpt_comments_widget', 'description' => __('A widget that displays your latest custom post type comments', 'cl_cpt_comments_widget') );

		/* Widget control settings. */
		$control_ops = array( 'width' => 250, 'height' => 350, 'id_base' => 'cl_cpt_comments_widget' );

		/* Create the widget. */
		$this->WP_Widget( 'cl_cpt_comments_widget', __('Latest custom post type comments', 'cl_cpt_comments_widget'), $widget_ops, $control_ops );
	}

	/**
	 * How to display the widget on the screen.
	 */
	function widget( $args, $instance ) {
		extract( $args );

		/* Our variables from the widget settings. */
		$title = apply_filters('widget_title', $instance['title'] );
		$number = $instance['number'];
		
		/* Before widget (defined by themes). */
		echo $before_widget;

		/* Display the widget title if one was input (before and after defined by themes). */
		if ( $title )
			echo '
' . $title . '
';

		/* Get recent comments */
		global $wpdb;
		$sql = "SELECT * FROM $wpdb->comments LEFT OUTER JOIN $wpdb->posts ON ($wpdb->comments.comment_post_ID = $wpdb->posts.ID) WHERE comment_approved = '1' AND comment_type = '' AND post_password = '' AND post_type='your_custom_post_type' ORDER BY comment_date_gmt DESC LIMIT $number";
		$comments = $wpdb->get_results($sql);
		echo '
';
		foreach ($comments as $comment) {
			if ($comment->user_id != 0) {
				$curent_userdata = get_userdata($comment->user_id);
				$current_comment_display_name = $curent_userdata->display_name;
			} else {
				$current_comment_display_name = strip_tags($comment->comment_author);
			}						
		?>
			

				
comment_post_ID); ?>
				
 says:
comment_content); ?>
			
		';

		/* After widget (defined by themes). */
		echo $after_widget;
	}

	/**
	 * Update the widget settings.
	 */
	function update( $new_instance, $old_instance ) {
		$instance = $old_instance;

		/* Strip tags for title and name to remove HTML (important for text inputs). */
		$instance['title'] = strip_tags( $new_instance['title'] );
		$instance['number'] = strip_tags( $new_instance['number'] );

		return $instance;
	}


	function form( $instance ) {

		/* Set up some default widget settings. */
		$defaults = array( 'title' => __('Latest CPT Comments'), 'number' => __('5'));
		$instance = wp_parse_args( (array) $instance, $defaults ); ?>

		
		

			
			
		

		
		

			
			
		
		



	

Next you need to copy this code, put it inside the plugins directory, activate the plugin and you’re ready to go. Don’t forget to change the custom post type to your own.