interface HelpTopicPluginInterface

interface HelpTopicPluginInterface extends PluginInspectionInterface, DerivativeInspectionInterface, CacheableDependencyInterface {
    
    /**
     * Returns the label of the topic.
     *
     * @return string
     *   The label of the topic.
     */
    public function getLabel();
    
    /**
     * Returns the body of the topic.
     *
     * @return array
     *   A render array representing the body.
     */
    public function getBody();
    
    /**
     * Returns whether this is a top-level topic or not.
     *
     * @return bool
     *   TRUE if this is a topic that should be displayed on the Help topics
     *   list; FALSE if not.
     */
    public function isTopLevel();
    
    /**
     * Returns the IDs of related topics.
     *
     * @return string[]
     *   Array of the IDs of related topics.
     */
    public function getRelated();
    
    /**
     * Returns the URL for viewing the help topic.
     *
     * @param array $options
     *   (optional) See
     *   \Drupal\Core\Routing\UrlGeneratorInterface::generateFromRoute() for the
     *    available options.
     *
     * @return \Drupal\Core\Url
     *   A URL object containing the URL for viewing the help topic.
     */
    public function toUrl(array $options = []);
    
    /**
     * Returns a link for viewing the help topic.
     *
     * @param string|null $text
     *   (optional) Link text to use for the link. If NULL, defaults to the
     *   topic title.
     * @param array $options
     *   (optional) See
     *   \Drupal\Core\Routing\UrlGeneratorInterface::generateFromRoute() for the
     *    available options.
     *
     * @return \Drupal\Core\Link
     *   A link object for viewing the topic.
     */
    public function toLink($text = NULL, array $options = []);

}