class VarnishCache in Varnish 7

Varnish cache implementation.

This cache implementation can be used together with Varnish. You can't really use it to store or get any values, but you can use it to purge your caches. This cache implementation should ONLY be used for cache_page and no other cache bin!

Hierarchy

• class \VarnishCache implements DrupalCacheInterface

File

./varnish.cache.inc, line 16

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

class VarnishCache implements DrupalCacheInterface {
  protected $bin;
  public function __construct($bin) {
    $this->bin = $bin;
  }
  public function get($cid) {
    return FALSE;
  }
  public function getMultiple(&$cids) {
    return array();
  }
  public function set($cid, $data, $expire = CACHE_PERMANENT) {

    // We won't do anything here.
  }
  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,
        ));
      }
    }
  }
  public function isEmpty() {
    return FALSE;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
VarnishCache::$bin	protected	property
VarnishCache::clear	public	function	Expires data from the cache. Overrides DrupalCacheInterface::clear
VarnishCache::get	public	function	Returns data from the persistent cache. Overrides DrupalCacheInterface::get
VarnishCache::getMultiple	public	function	Returns data from the persistent cache when given an array of cache IDs. Overrides DrupalCacheInterface::getMultiple
VarnishCache::isEmpty	public	function	Checks if a cache bin is empty. Overrides DrupalCacheInterface::isEmpty
VarnishCache::set	public	function	Stores data in the persistent cache. Overrides DrupalCacheInterface::set
VarnishCache::__construct	public	function