cas_mock_server-8.x-1.0/src/ServerManager.php

<?php

declare(strict_types=1);

namespace Drupal\cas_mock_server;

use Drupal\cas_mock_server\Config\CasMockServerConfigOverrider;
use Drupal\Core\Cache\CacheTagsInvalidatorInterface;
use Drupal\Core\State\StateInterface;

/**
 * Service providing methods to start and stop the mock server.
 */
class ServerManager implements ServerManagerInterface {

  /**
   * The key that identifies the state of the mock server in the state storage.
   */
  const STATE_KEY_SERVER_STATE = 'cas_mock_server.state';

  /**
   * Constructs a ServerManager.
   *
   * @param \Drupal\Core\State\StateInterface $state
   *   The state key/value store.
   * @param \Drupal\Core\Cache\CacheTagsInvalidatorInterface $cacheTagsInvalidator
   *   The cache tags invalidator.
   */
  public function __construct(protected StateInterface $state, protected CacheTagsInvalidatorInterface $cacheTagsInvalidator) {
  }

  /**
   * {@inheritdoc}
   */
  public function start(): void {
    if ($this->isServerActive()) {
      return;
    }

    $this->state->set(self::STATE_KEY_SERVER_STATE, TRUE);
    $this->invalidateCache();
  }

  /**
   * {@inheritdoc}
   */
  public function stop(): void {
    if (!$this->isServerActive()) {
      return;
    }

    $this->state->set(self::STATE_KEY_SERVER_STATE, FALSE);
    $this->invalidateCache();
  }

  /**
   * {@inheritdoc}
   */
  public function isServerActive(): bool {
    return $this->state->get(self::STATE_KEY_SERVER_STATE, FALSE);
  }

  /**
   * Invalidates caches that contain config overridden by us.
   *
   * We are overriding the configuration of the CAS module so that it uses our
   * mock server when it is activated. When the mock server is enabled or
   * disabled we need to invalidate any caches that contain the CAS module
   * config so that it will not make a server connection using stale data.
   */
  protected function invalidateCache(): void {
    // Sideload the cache tags invalidator to circumvent a possible circular
    // dependency.
    // This can happen when a cache tag invalidator depends on configuration
    // provided by the ConfigFactory service. ConfigFactory will include our
    // CasMockServerConfigOverrider in the dependency chain, and since this in
    // turn depends on this class a circular dependency will be created.
    $this->cacheTagsInvalidator->invalidateTags([CasMockServerConfigOverrider::CACHE_TAG]);
  }

}