Action links available options / caching

The following example implements an action link in Drupal 8 with the requirement of user-specific caching. This should allow you to hide/display the action link for the different users on your page. Providing different titles for different users should also work.

mymodule.links.action.yml:

entity.mymodule.add_form:
  class: DrupalmymodulePluginMenuLocalActionUserAction
  route_name: entity.mymodule.add_form
  title: 'Link to Add Form'
  appears_on:
    - entity.mymodule.collection

mymodule/src/Plugin/Menu/LocalAction/UserAction.php:

<?php

namespace DrupalrandomintroPluginMenuLocalAction;

use DrupalCoreMenuLocalActionDefault;
use SymfonyComponentDependencyInjectionContainerInterface;
use DrupalCoreSessionAccountInterface;
use DrupalCoreRoutingRouteProviderInterface;
use DrupalCoreRoutingRouteMatchInterface;

/**
 * Defines a test local action plugin class.
 */
class UserAction extends LocalActionDefault {

  /**
   * The current user.
   *
   * @var DrupalCoreSessionAccountInterface
   */
  protected $currentUser;


  /**
   * {@inheritdoc}
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, RouteProviderInterface $route_provider, AccountInterface $current_user) {
    parent::__construct($configuration, $plugin_id, $plugin_definition, $route_provider);

    $this->currentUser = $current_user;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static(
      $configuration,
      $plugin_id,
      $plugin_definition,
      $container->get('router.route_provider'),
      $container->get('current_user')
    );
  }

  /**
   * {@inheritdoc}
   */
  public function getCacheContexts() {
    return parent::getCacheContexts() + ['user'];
  }

  /**
   * {@inheritdoc}
   */
  public function getRouteParameters(RouteMatchInterface $route_match) {
    // If the user is not Anonymous.
    if (!$this->currentUser->isAnonymous()) {
      // Getting the uid.
      $uid = $this->currentUser->id();
      // Adding the link.
      return ['user' => $uid];
    }
    return [];
  }

}