Hi all,
In first, I'm not familiar with the memcache object.
I had to develop a memcache object wich must work with our actual sessions
files (and not database session).
I used the init handler session and his callback functions.
But in the architecture of the web site in our production environment, we
have 2 web server with memcache installed (on both) behind a load balancer.
And the cached session must be accessible on both of them.
This is my class :
class MemcacheSession {
/********************************************
* CONSTANTS *
* ******************************************/
const DEFAULT_HOST = "127.0.0.1";
const DEFAULT_PORT = 11211;
const DEFAULT_COMPRESSION = MEMCACHE_COMPRESSED;
/*******************************************
* PRIVATE VARS *
* ******************************************/
private $servers;
private $memcache;
/*******************************************
* PUBLIC VARS *
* ******************************************/
public $lifeTime;
/*******************************************
* SINGLETON *
* ******************************************/
private static $instance = null;
public static function getInstance() {
if (empty(self::$instance)) {
self::$instance = new MemcacheSession();
}
return self::$instance;
}
/*******************************************
* CONSTRUCTOR *
* ******************************************/
private function __construct() {
$this->memcache = new Memcache;
$this->servers = array();
}
/*******************************************
* PUBLIC METHODS *
* ******************************************/
public function start() {
$this->initSaveHandler();
if(empty($this->servers)){
$this->servers[] = array(self::DEFAULT_HOST=>self::DEFAULT_PORT);
}
for ($i = 0, $n = count($this->servers); $i < $n; ++$i){
$this->memcache->addServer(key($this->servers[$i]),
current($this->servers[$i]));
}
}
public function addServer(array $server){
$this->servers[] = array($server[0]=>$server[1]);
}
public function addMultipleServer(array $server){
for ($i = 0, $n = count($server); $i < $n; ++$i){
$this->servers[] = $server[$i];
}
}
/*******************************************
* PRIVATE METHODS *
* ******************************************/
private function initSaveHandler(){
session_set_save_handler(array(&$this,"sessionOpenCb"),
array(&$this,"sessionCloseCb"),
array(&$this,"sessionReadCb"),
array(&$this,"sessionWriteCb"),
array(&$this,"sessionDestroyCb"),
array(&$this,"sessionGcCb"));
}
/*******************************************
* CALLBACK METHODS *
* ******************************************/
public function sessionOpenCb($savePath, $sessName) {
return $this->lifeTime = get_cfg_var("session.gc_maxlifetime");
}
public function sessionCloseCb() {
return $this->sessionGcCb(ini_get('session.gc_maxlifetime'));
}
public function sessionReadCb($sessID) {
return $this->memcache->get($sessID);
}
public function sessionWriteCb($sessID,$sessData) {
return $this->memcache->set($sessID, $sessData,
self::DEFAULT_COMPRESSION, $this->lifeTime) or false;
}
public function sessionDestroyCb($sessID) {
return $this->memcache->delete($sessID);
}
public function sessionGcCb($sessMaxLifeTime) {}
}
And his implementation :
$memcacheSess = MemcacheSession::getInstance();
$memcacheSess->addServer(array('192.168.0.1','11211'));
$memcacheSess->addServer(array('192.168.0.2','11211'));
$memcacheSess->start();
session_start();
And after we use the standard procedure of $_SESSION object.
In the memcache log (on both servers) i can see some get/set/stored/deleted
events.
But the session is not accessible on the both server and i can't access to
my information where the session is not write by the $_SESSION object.
Someone can help me on this particular problem ?
Thanks a lot.
Mickaël.
