CleanerCacheClearEventSubscriber.php in Cleaner 8.2

Namespace

Drupal\cleaner\EventSubscriber

File

src/EventSubscriber/CleanerCacheClearEventSubscriber.php

<?php

namespace Drupal\cleaner\EventSubscriber;

use Drupal\cleaner\Event\CleanerRunEvent;
use Drupal\Core\Cache\CacheBackendInterface;
use Drupal\Core\Config\ConfigFactoryInterface;
use Drupal\Core\Database\Connection;
use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
use Drupal\Core\Logger\LoggerChannelFactoryInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**
 * Class CleanerCacheClearEventSubscriber.
 *
 * @package Drupal\cleaner\EventSubscriber
 */
class CleanerCacheClearEventSubscriber implements EventSubscriberInterface, ContainerInjectionInterface {

  /**
   * Database connection.
   *
   * @var \Drupal\Core\Database\Connection
   */
  protected $database;

  /**
   * Config object.
   *
   * @var \Drupal\Core\Config\ImmutableConfig
   */
  protected $config;

  /**
   * Cache backend.
   *
   * @var \Drupal\Core\Cache\CacheBackendInterface
   */
  protected $cacheBackend;

  /**
   * Logger channel.
   *
   * @var \Drupal\Core\Logger\LoggerChannelInterface
   */
  protected $loggerChannel;

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() {
    $events[CleanerRunEvent::CLEANER_RUN][] = [
      'clearCaches',
      100,
    ];
    return $events;
  }

  /**
   * CleanerCacheClearEventSubscriber constructor.
   *
   * @param \Drupal\Core\Database\Connection $database
   *   Database connection.
   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
   *   Config factory.
   * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
   *   Cache backend.
   * @param \Drupal\Core\Logger\LoggerChannelFactoryInterface $logger_channel_factory
   *   Logger channel factory.
   */
  public function __construct(Connection $database, ConfigFactoryInterface $config_factory, CacheBackendInterface $cache_backend, LoggerChannelFactoryInterface $logger_channel_factory) {
    $this->database = $database;
    $this->config = $config_factory
      ->get('cleaner.settings');
    $this->cacheBackend = $cache_backend;
    $this->loggerChannel = $logger_channel_factory
      ->get('cleaner');
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) {
    return new static($container
      ->get('database'), $container
      ->get('config.factory'), $container
      ->get('cache.default'), $container
      ->get('logger.factory'));
  }

  /**
   * Cleaner caches clearing.
   */
  public function clearCaches() {
    if ($this->config
      ->get('cleaner_clear_cache')) {
      $cleared = 0;

      // First clearing caches for the static caches.
      $this->cacheBackend
        ->deleteAll();

      // Prepare cache tables list.
      $tables = (array) $this
        ->cleanerGetCacheTables();

      // Ensure tables exist.
      if (!empty($tables)) {

        // Clears the cache tables
        // and increments the cleared entries count.
        $cleared += (int) $this
          ->performClearing($tables);
      }
      $this
        ->writeToLog($cleared);
    }
  }

  /**
   * Perform caches clearing work.
   *
   * @param array $tables
   *   Table names array.
   *
   * @return int
   *   Amount of cleared tables.
   */
  protected function performClearing(array $tables) {
    $cleared = 0;
    foreach ($tables as $table) {
      if (!$this->database
        ->schema()
        ->tableExists($table)) {
        continue;
      }
      if ($this->database
        ->query("TRUNCATE {$table}")
        ->execute()) {
        $cleared++;
      }
    }
    return $cleared;
  }

  /**
   * Get cache tables list.
   *
   * @return array
   *   Cache tables list array.
   */
  protected function cleanerGetCacheTables() {
    $tables = [];
    $db_name = $this
      ->getDatabaseName();
    if (!empty($db_name)) {
      $query = $this->database
        ->select('INFORMATION_SCHEMA.TABLES', 'tables');
      $query
        ->fields('tables', [
        'table_name',
        'table_schema',
      ]);
      $query
        ->condition('table_schema', $db_name);
      $query
        ->condition('table_name', 'cache_%', 'LIKE');

      // Exclude cachetags table.
      $query
        ->condition('table_name', 'cachetags', '<>');
      $tables = $query
        ->execute()
        ->fetchCol();
    }
    return $tables;
  }

  /**
   * Get active database name.
   *
   * @return string|null
   *   Database name.
   */
  protected function getDatabaseName() {
    $options = $this->database
      ->getConnectionOptions();
    return isset($options['database']) ? $options['database'] : NULL;
  }

  /**
   * Write a message about successful or not cache tables clearing.
   *
   * @param int $count
   *   Count of tables cleared. Defaults to 0.
   */
  protected function writeToLog($count = 0) {
    if ($count > 0) {
      $this->loggerChannel
        ->info('Cleared @count cache tables by Cleaner.', [
        '@count' => $count,
      ]);
    }
    else {
      $this->loggerChannel
        ->error('There are no selected cache tables in the database.');
    }
  }

}

Classes

Name	Description
CleanerCacheClearEventSubscriber	Class CleanerCacheClearEventSubscriber.