public function VarnishCache::clear in Varnish 7

Expires data from the cache.

If called without arguments, expirable entries will be cleared from the cache_page and cache_block bins.

Parameters

$cid: If set, the cache ID or an array of cache IDs. Otherwise, all cache entries that can expire are deleted. The $wildcard argument will be ignored if set to NULL.

$wildcard: If TRUE, the $cid argument must contain a string value and cache IDs starting with $cid are deleted in addition to the exact cache ID specified by $cid. If $wildcard is TRUE and $cid is '*', the entire cache is emptied.

Overrides DrupalCacheInterface::clear

File

./varnish.cache.inc, line 35

Cache include file, to be used in settings.php file.

Class

VarnishCache

Varnish cache implementation.

Code

public function clear($cid = NULL, $wildcard = FALSE) {
  global $user;

  // Check that we really want to do a cache flush.
  if (!module_exists('varnish') || variable_get('varnish_cache_clear', VARNISH_DEFAULT_CLEAR) == VARNISH_NO_CLEAR || !variable_get('varnish_cache_clear', VARNISH_DEFAULT_CLEAR) && !variable_get('varnish_flush_cron', 0) || variable_get('varnish_flush_cron', 0) && !lock_may_be_available('cron')) {
    return;
  }
  if (empty($cid) && variable_get('varnish_cache_clear', 1)) {
    if (variable_get('cache_lifetime', 0)) {

      // We store the time in the current user's $user->cache variable which
      // will be saved into the sessions bin by _drupal_session_write(). We
      // then simulate that the cache was flushed for this user by not
      // returning cached data that was cached before the timestamp.
      $user->cache = REQUEST_TIME;
      $cache_flush = variable_get('cache_flush_' . $this->bin, 0);
      if ($cache_flush == 0) {

        // This is the first request to clear the cache, start a timer.
        variable_set('cache_flush_' . $this->bin, REQUEST_TIME);
      }
      elseif (REQUEST_TIME > $cache_flush + variable_get('cache_lifetime', 0)) {

        // Clear the cache for everyone, cache_lifetime seconds have
        // passed since the first request to clear the cache.
        varnish_purge_all_pages();
        variable_set('cache_flush_' . $this->bin, 0);
      }
    }
    else {

      // No minimum cache lifetime, flush all temporary cache entries now.
      varnish_purge_all_pages();
    }
  }
  else {
    if ($wildcard) {
      if ($cid == '*') {
        varnish_purge_all_pages();
      }
      else {
        $host = _varnish_get_host();
        $base = base_path();
        $purge = $cid . '(.*)';
        varnish_purge($host, '^' . $base . $purge . '$');
      }
    }
    elseif (is_array($cid)) {
      varnish_expire_cache($cid);
    }
    else {
      varnish_expire_cache(array(
        $cid,
      ));
    }
  }
}