/**
* Checks for the existence of a key in the cache.
*
* @param string $data_group The Data Group to look in.
* @param string $key The key to look up.
* @return boolean Indicating existence
*/
function exists($data_group, $key)
{
if ($this->_cache === null) {
return false;
}
return $this->_cache->exists("{$data_group}-{$key}");
}
function check_dl_hit(&$context, &$dl_config)
{
if ($this->_no_cache || $this->_live_mode) {
return false;
}
$dl_request_id = 'DL' . $this->generate_request_identifier($context, $dl_config);
$this->_meta_cache->open();
if (!$this->_meta_cache->exists($dl_request_id)) {
$this->_meta_cache->close();
unset($dl_request_id);
return false;
}
$dl_content_id = $this->_meta_cache->get($dl_request_id);
if (!$this->_meta_cache->exists($dl_content_id)) {
// No expiry information (or other content metadata) in cache
$this->_meta_cache->close();
unset($dl_content_id, $dl_request_id);
return false;
}
$dl_metadata = $this->_meta_cache->get($dl_content_id);
$this->_meta_cache->close();
if (time() > $dl_metadata['expires']) {
// DL content expired
unset($dl_metadata, $dl_content_id, $dl_request_id);
return false;
}
unset($dl_metadata);
$this->_data_cache->open();
if (!$this->_data_cache->exists($dl_content_id)) {
// Ghost read, we have everything but the actual content in cache
unset($dl_content_id, $dl_request_id);
$this->_data_cache->close();
return false;
}
echo $this->_data_cache->get($dl_content_id);
unset($dl_content_id, $dl_request_id);
$this->_data_cache->close();
return true;
}
