memCache = true; /// should we use memCache instead of caching in files
$db->memCacheHost = array($ip1, $ip2, $ip3);
$db->memCachePort = 11211; /// this is default memCache port
$db->memCacheCompress = false; /// Use 'true' to store the item compressed (uses zlib)
$db->Connect(...);
$db->CacheExecute($sql);
Note the memcache class is shared by all connections, is created during the first call to Connect/PConnect.
Class instance is stored in $ADODB_CACHE
*/
class ADODB_Cache_MemCache {
var $createdir = false; // create caching directory structure?
//-----------------------------
// memcache specific variables
var $hosts; // array of hosts
var $port = 11211;
var $compress = false; // memcache compression with zlib
var $_connected = false;
var $_memcache = false;
function ADODB_Cache_MemCache(&$obj)
{
$this->hosts = $obj->memCacheHost;
$this->port = $obj->memCachePort;
$this->compress = $obj->memCacheCompress;
}
// implement as lazy connection. The connection only occurs on CacheExecute call
function connect(&$err)
{
if (!function_exists('memcache_pconnect')) {
$err = 'Memcache module PECL extension not found!';
return false;
}
$memcache = new MemCache;
if (!is_array($this->hosts)) $this->hosts = array($this->hosts);
$failcnt = 0;
foreach($this->hosts as $host) {
if (!@$memcache->addServer($host,$this->port,true)) {
$failcnt += 1;
}
}
if ($failcnt == sizeof($this->hosts)) {
$err = 'Can\'t connect to any memcache server';
return false;
}
$this->_connected = true;
$this->_memcache = $memcache;
return true;
}
// returns true or false. true if successful save
function writecache($filename, $contents, $debug, $secs2cache)
{
if (!$this->_connected) {
$err = '';
if (!$this->connect($err) && $debug) ADOConnection::outp($err);
}
if (!$this->_memcache) return false;
if (!$this->_memcache->set($filename, $contents, $this->compress ? MEMCACHE_COMPRESSED : 0, $secs2cache)) {
if ($debug) ADOConnection::outp(" Failed to save data at the memcached server!
\n");
return false;
}
return true;
}
// returns a recordset
function readcache($filename, &$err, $secs2cache, $rsClass)
{
$false = false;
if (!$this->_connected) $this->connect($err);
if (!$this->_memcache) return $false;
$rs = $this->_memcache->get($filename);
if (!$rs) {
$err = 'Item with such key doesn\'t exists on the memcached server.';
return $false;
}
// hack, should actually use _csv2rs
$rs = explode("\n", $rs);
unset($rs[0]);
$rs = join("\n", $rs);
$rs = unserialize($rs);
if (! is_object($rs)) {
$err = 'Unable to unserialize $rs';
return $false;
}
if ($rs->timeCreated == 0) return $rs; // apparently have been reports that timeCreated was set to 0 somewhere
$tdiff = intval($rs->timeCreated+$secs2cache - time());
if ($tdiff <= 2) {
switch($tdiff) {
case 2:
if ((rand() & 15) == 0) {
$err = "Timeout 2";
return $false;
}
break;
case 1:
if ((rand() & 3) == 0) {
$err = "Timeout 1";
return $false;
}
break;
default:
$err = "Timeout 0";
return $false;
}
}
return $rs;
}
function flushall($debug=false)
{
if (!$this->_connected) {
$err = '';
if (!$this->connect($err) && $debug) ADOConnection::outp($err);
}
if (!$this->_memcache) return false;
$del = $this->_memcache->flush();
if ($debug)
if (!$del) ADOConnection::outp("flushall: failed!
\n");
else ADOConnection::outp("flushall: succeeded!
\n");
return $del;
}
function flushcache($filename, $debug=false)
{
if (!$this->_connected) {
$err = '';
if (!$this->connect($err) && $debug) ADOConnection::outp($err);
}
if (!$this->_memcache) return false;
$del = $this->_memcache->delete($filename);
if ($debug)
if (!$del) ADOConnection::outp("flushcache: $key entry doesn't exist on memcached server!
\n");
else ADOConnection::outp("flushcache: $key entry flushed from memcached server!
\n");
return $del;
}
// not used for memcache
function createdir($dir, $hash)
{
return true;
}
}
?>