PHP Classes

File: adodb/adodb-memcache.lib.inc.php

Recommend this page to a friend!
  Classes of Isaac Trenado Mx   PHP MySQL JSON Manager   adodb/adodb-memcache.lib.inc.php   Download  
File: adodb/adodb-memcache.lib.inc.php
Role: Auxiliary script
Content type: text/plain
Description: Auxiliary script
Class: PHP MySQL JSON Manager
Build and Execute SQL queries with results in JSON
Author: By
Last change:
Date: 8 years ago
Size: 5,036 bytes
 

Contents

Class file image Download
<?php

// security - hide paths
if (!defined('ADODB_DIR')) die();

global
$ADODB_INCLUDED_MEMCACHE;
$ADODB_INCLUDED_MEMCACHE = 1;

global
$ADODB_INCLUDED_CSV;
if (empty(
$ADODB_INCLUDED_CSV)) include(ADODB_DIR.'/adodb-csvlib.inc.php');

/*

  V5.18 3 Sep 2012 (c) 2000-2012 John Lim (jlim#natsoft.com). All rights reserved.
  Released under both BSD license and Lesser GPL library license.
  Whenever there is any discrepancy between the two licenses,
  the BSD license will take precedence. See License.txt.
  Set tabs to 4 for best viewing.
 
  Latest version is available at http://adodb.sourceforge.net

Usage:
 
$db = NewADOConnection($driver);
$db->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!<br>\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!<br>\n");
                else
ADOConnection::outp("flushall: succeeded!<br>\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!<br>\n");
                else
ADOConnection::outp("flushcache: $key entry flushed from memcached server!<br>\n");
               
            return
$del;
        }
       
       
// not used for memcache
       
function createdir($dir, $hash)
        {
            return
true;
        }
    }

?>