Print results of WP_Query to wp-admin/upload.php within delete_attachment hook?

Hi all,

I am working on a plugin feature that checks for usage of image media before deletion – specifically within Advanced Custom Fields image fields in posts of a custom post type, but this part is not the issue.

I can use a WP_Query/meta_query to successfully check for this scenario, but the problem is that I would like to print the results of my WP_Query to the wp-admin/upload.php page so that administrators can understand if the attachment was deleted successfully, or if not, why. I am not sure how to make this possible.

Here is example code I am testing with now. Currently I am writing the results of my check to wp-content/debug.log. It would be better if administrators could see that in wp-admin.

// Prevent deletion of attached media
function check_acf_image_field_usage( $attachment_id ) {

    // Relevant meta keys are the image field names
    $image_field_names = array(
        'acf_image_field_name_example_1',
        'acf_image_field_name_example_2',
        'acf_image_field_name_example_3',
    );

    // Create a meta query from $image_field_names starting with 'relation' => 'OR'
    $image_fields_meta_query = array('relation' => 'OR');
    for ($i = 0; $i < count($image_field_names); $i++)  {
        $newArray = array(
            'key' => $image_field_names[$i],
            'value' => $attachment_id,
            'compare' => '=',
        );
        array_push($image_fields_meta_query, $newArray);
    }

    $args = array(
        'post_type'  => 'custom-post-type',
        'meta_query' => $image_fields_meta_query
    );
    $query = new WP_Query($args);

    // If 0 posts were found in the meta_query
    if (count($query->posts) === 0) {
        // CHANGE THIS write_log FUNCTION INTO SOMETHING THAT WILL OUTPUT TO wp-admin?
        write_log("The attachment that was requested to be deleted is included in " . count($query->posts) . " posts, so it will be deleted.");

        // Proceed to delete the attachment.
        return;
    
    // If 1 or more posts were found in the meta_query
    } else if (count($query->posts) > 0) {
        // CHANGE THESE write_log FUNCTIONS INTO SOMETHING THAT WILL OUTPUT TO wp-admin?
        write_log("The attachment that was requested to be deleted is included in " . count($query->posts) . " posts.");
        write_log('It is currently attached as an image to:');

        // Loop through meta query results to log each discovered post containing the attachment
        for ($i = 0; $i < count($query->posts); $i++)  {
            write_log($query->posts[$i]->ID . ' - ' . $query->posts[$i]->post_title);
        }

        // Stop WordPress execution so that the attachment is not deleted.
        $message = 'Sorry, this attachment cannot be deleted.'; 
        wp_die($message);
    }
}
add_action( 'delete_attachment', 'check_acf_image_field_usage' );

// Generic function for writing data to wp-content/debug.log file
function write_log( $log ) {

    if ( true === WP_DEBUG ) {

        if ( is_array($log) || is_object($log) ) {
            error_log( print_r($log, true) );
        } else {
            error_log( $log );
        }
        
    }

}

Here are the requirements:
– Print results of a WP_Query to a wp-admin page (upload.php) that happens within the ‘delete_attachment’ hook.
– All that matters to me is that administrators see the results of the query, I don’t care much about how or where it appears.
– In other words, the content for the admin notification depends on the WP_Query results, which runs when an admin tries to delete an attachment.
– What is the best way to print information from a WP_Query to a wp-admin page at the time the hook is called?
– Simply using an admin notice doesn’t seem to be a solution because that shows the same data every time the page is loaded, and the WP_Query does not run when the page loads.

Additionally, I am wondering is there a better method than using wp_die() to stop the attachment from being deleted?

Thanks for your help!