function memcache_storage_wildcard_flush in Memcache Storage 7

Invalidates all cache which should be invalid because of wildcard flushes.

1 string reference to 'memcache_storage_wildcard_flush'

memcache_storage_init in ./memcache_storage.module

Implements hook_init().

File

./memcache_storage.module, line 130

Provides hook implementation for Memcache Storage module.

Code

function memcache_storage_wildcard_flush() {

  // Get list of cache bins which are stored in memcached.
  $cache_bins = _memcache_storage_memcached_cache_bins();
  foreach ($cache_bins as $bin) {

    // Get instance of MemcacheStorage from static cache.
    $object = _cache_get_object($bin);
    if (!$object instanceof MemcacheStorage) {
      continue;
    }

    // Check if the current cache bin has not yet invalidated wildcards.
    $wildcards = $object
      ->getWildcards();
    if (empty($wildcards)) {
      continue;
    }

    // Load a list of all cache ids stored in the cache bin.
    $cache_ids = $object
      ->getCacheIDs();

    // Check if each cache may match any wildcard, and mark it as "delete
    // candidate" if it is true.
    $delete_ids = array();
    foreach ($wildcards as $wildcard => $flush_timestamp) {
      foreach ($cache_ids as $cache_id => $cache_created) {
        if ($cache_created <= $flush_timestamp) {
          if (strpos($cache_id, $wildcard) === 0) {
            $delete_ids[] = $cache_id;
          }
        }
      }
    }

    // Clear all cache items which are now invalid.
    if (!empty($delete_ids)) {
      $object
        ->clear($delete_ids);
    }

    // No need to store the information about wildcards for this cache bin
    // anymore - all invalid items have been deleted.
    $object
      ->clear('memcache_storage_wildcards');
  }

  // Set a timestamp of the latest wildcards invalidation.
  variable_set('memcache_storage_last_wildcards_flush', REQUEST_TIME);
}