/**
* Calls the corresponding function in the block and executes the data retrieval function.
* @return \SimpleXMLElement The XML data tree
*/
public final function callMemcacheBlock()
{
$callback = $this->getCallback();
$db = $this->getDatabase();
$mem = new \System\Cache\Memcache\Memcache();
$xml = null;
if ($mem->keyExists($this->key)) {
$xmlString = $mem->get($this->key);
if ($xmlString) {
//suppress warning here in case of malformed xml
$xml = @simplexml_load_string($xmlString);
if ($xml instanceof \SimpleXMLElement) {
return $xml;
} else {
$errorLogger = \System\Log\ErrorLogger::getInstance();
$errorLogger->out('[MemcacheBlock] Could not read memcache key ' . $this->key . ' as XML. Regenerating.', \System\Log\LoggerLevel::LEVEL_WARNING);
}
}
}
if (is_callable($callback)) {
$xml = call_user_func($callback, $this);
$mem->store($this->key, $xml->asXML(), $this->timeout);
} else {
throw new \System\Error\Exception\InvalidMethodException('The given callback cannot be called. Does it exist and is it public?');
}
return $xml;
}
/**
* Provides functionality to check if a given IP is blocked by a common blacklist
* Do note this system requires the use of the PERMABAN_* directives
* @param string The IP Address to check.
* @return bool True if the IP is allowed, false otherwise
*/
public static final function isIPAllowed($ipAddress)
{
//if there is an explicit empty PERMABAN, we accept everything
if (PERMABAN_HOST == '') {
return true;
}
$allowed = true;
$mc = new \System\Cache\Memcache\Memcache();
$key = self::MEMCACHE_KEY . $ipAddress;
//we get the value from the memcache, and only recheck if the blocked user is on it.
if (!($allowed = $mc->get($key))) {
$db = \System\Db\Database::getConnection(PERMABAN_HOST, PERMABAN_USER, PERMABAN_PASS, PERMABAN_NAME, PERMABAN_PORT);
$query = new \System\Db\Query($db, \System\HTTP\Visitor\PermaBan\SQL_PERMABAN_CHECK_PERMABAN);
$query->bind($ipAddress, \System\Db\QueryType::TYPE_STRING);
$results = $db->query($query);
$allowed = $results->count() == 0;
$mc->store($key, $allowed);
}
return $allowed;
}
