Mem Cached Component

Mem Cached Component

Component:

This is mem cached component for cakePHP. Please create a component as mem_cache.php in the componet folder .

/**
* Wrapper for Memcache, v. 0.1
*
* By Jiri Kupiainen (http://jirikupiainen.com/)
*
* You are free to do whatever you please with this code. Enjoy.
*/
define('CACHE_LITE_ERROR_RETURN', 1);
define('CACHE_LITE_ERROR_DIE', 8);
//$memcache_obj = memcache_connect(array('XX.XXX.XX.XX','XX.XXX.XX.XX'), 11211);
class MemCacheComponent extends Object {
// --- Private properties ---
/**
* Directory where to put the cache files
* (make sure to add a trailing slash)
*
* @var string $_cacheDir
*/
var $_cacheDir = '/tmp/';

/**
* Enable / disable caching
*
* (can be very usefull for the debug of cached scripts)
*
* @var boolean $_caching
*/
var $_caching = true;

/**
* Cache lifetime (in seconds)
*
* If null, the cache is valid forever.
*
* @var int $_lifeTime
*/
var $_lifeTime = 3600;

/**
* Enable / disable fileLocking
*
* (can avoid cache corruption under bad circumstances)
*
* @var boolean $_fileLocking
*/
var $_fileLocking = true;

/**
* Timestamp of the last valid cache
*
* @var int $_refreshTime
*/
var $_refreshTime;

/**
* File name (with path)
*
* @var string $_file
*/
var $_file;

/**
* File name (without path)
*
* @var string $_fileName
*/
var $_fileName;

/**
* Enable / disable write control (the cache is read just after writing to detect corrupt entries)
*
* Enable write control will lightly slow the cache writing but not the cache reading
* Write control can detect some corrupt cache files but maybe it's not a perfect control
*
* @var boolean $_writeControl
*/
var $_writeControl = true;

/**
* Enable / disable read control
*
* If enabled, a control key is embeded in cache file and this key is compared with the one
* calculated after the reading.
*
* @var boolean $_writeControl
*/
var $_readControl = true;

/**
* Type of read control (only if read control is enabled)
*
* Available values are :
* 'md5' for a md5 hash control (best but slowest)
* 'crc32' for a crc32 hash control (lightly less safe but faster, better choice)
* 'strlen' for a length only test (fastest)
*
* @var boolean $_readControlType
*/
var $_readControlType = 'crc32';

/**
* Pear error mode (when raiseError is called)
*
* (see PEAR doc)
*
* @see setToDebug()
* @var int $_pearErrorMode
*/
var $_pearErrorMode = CACHE_LITE_ERROR_RETURN;

/**
* Current cache id
*
* @var string $_id
*/
var $_id;

/**
* Current cache group
*
* @var string $_group
*/
var $_group;

/**
* Enable / Disable "Memory Caching"
*
* NB : There is no lifetime for memory caching !
*
* @var boolean $_memoryCaching
*/
var $_memoryCaching = false;

/**
* Enable / Disable "Only Memory Caching"
* (be carefull, memory caching is "beta quality")
*
* @var boolean $_onlyMemoryCaching
*/
var $_onlyMemoryCaching = false;

/**
* Memory caching array
*
* @var array $_memoryCachingArray
*/
var $_memoryCachingArray = array();

/**
* Memory caching counter
*
* @var int $memoryCachingCounter
*/
var $_memoryCachingCounter = 0;

/**
* Memory caching limit
*
* @var int $memoryCachingLimit
*/
var $_memoryCachingLimit = 1000;

/**
* File Name protection
*
* if set to true, you can use any cache id or group name
* if set to false, it can be faster but cache ids and group names
* will be used directly in cache file names so be carefull with
* special characters...
*
* @var boolean $fileNameProtection
*/
var $_fileNameProtection = true;

/**
* Enable / disable automatic serialization
*
* it can be used to save directly datas which aren't strings
* (but it's slower)
*
* @var boolean $_serialize
*/
var $_automaticSerialization = false;

/**
* Disable / Tune the automatic cleaning process
*
* The automatic cleaning process destroy too old (for the given life time)
* cache files when a new cache file is written.
* 0 => no automatic cache cleaning
* 1 => systematic cache cleaning
* x (integer) > 1 => automatic cleaning randomly 1 times on x cache write
*
* @var int $_automaticCleaning
*/
var $_automaticCleaningFactor = 0;

/**
* Nested directory level
*
* Set the hashed directory structure level. 0 means "no hashed directory
* structure", 1 means "one level of directory", 2 means "two levels"...
* This option can speed up Cache_Lite only when you have many thousands of
* cache file. Only specific benchs can help you to choose the perfect value
* for you. Maybe, 1 or 2 is a good start.
*
* @var int $_hashedDirectoryLevel
*/
var $_hashedDirectoryLevel = 0;

/**
* Umask for hashed directory structure
*
* @var int $_hashedDirectoryUmask
*/
var $_hashedDirectoryUmask = 0700;

/**
* API break for error handling in CACHE_LITE_ERROR_RETURN mode
*
* In CACHE_LITE_ERROR_RETURN mode, error handling was not good because
* for example save() method always returned a boolean (a PEAR_Error object
* would be better in CACHE_LITE_ERROR_RETURN mode). To correct this without
* breaking the API, this option (false by default) can change this handling.
*
* @var boolean
*/
var $_errorHandlingAPIBreak = false;

// --- Public methods ---

/**
* Constructor
*
* $options is an assoc. Available options are :
* $options = array(
* 'cacheDir' => directory where to put the cache files (string),
* 'caching' => enable / disable caching (boolean),
* 'lifeTime' => cache lifetime in seconds (int),
* 'fileLocking' => enable / disable fileLocking (boolean),
* 'writeControl' => enable / disable write control (boolean),
* 'readControl' => enable / disable read control (boolean),
* 'readControlType' => type of read control 'crc32', 'md5', 'strlen' (string),
* 'pearErrorMode' => pear error mode (when raiseError is called) (cf PEAR doc) (int),
* 'memoryCaching' => enable / disable memory caching (boolean),
* 'onlyMemoryCaching' => enable / disable only memory caching (boolean),
* 'memoryCachingLimit' => max nbr of records to store into memory caching (int),
* 'fileNameProtection' => enable / disable automatic file name protection (boolean),
* 'automaticSerialization' => enable / disable automatic serialization (boolean),
* 'automaticCleaningFactor' => distable / tune automatic cleaning process (int),
* 'hashedDirectoryLevel' => level of the hashed directory system (int),
* 'hashedDirectoryUmask' => umask for hashed directory structure (int),
* 'errorHandlingAPIBreak' => API break for better error handling ? (boolean)
* );
*
* @param array $options options
* @access public
*/
function Cache_Lite($options = array(NULL))
{
foreach($options as $key => $value) {
$this->setOption($key, $value);
}
}
/**
* Generic way to set a Cache_Lite option
*
* see Cache_Lite constructor for available options
*
* @var string $name name of the option
* @var mixed $value value of the option
* @access public
*/
function setOption($name, $value)
{
$availableOptions = array('errorHandlingAPIBreak', 'hashedDirectoryUmask', 'hashedDirectoryLevel', 'automaticCleaningFactor', 'automaticSerialization', 'fileNameProtection', 'memoryCaching', 'onlyMemoryCaching', 'memoryCachingLimit', 'cacheDir', 'caching', 'lifeTime', 'fileLocking', 'writeControl', 'readControl', 'readControlType', 'pearErrorMode');
if (in_array($name, $availableOptions)) {
$property = '_'.$name;
$this->$property = $value;
}
}
/**
* Test if a cache is available and (if yes) return it
*
* @param string $id cache id
* @param string $group name of the cache group
* @param boolean $doNotTestCacheValidity if set to true, the cache validity won't be tested
* @return string data of the cache (else : false)
* @access public
*/
function get($id, $group = 'default', $doNotTestCacheValidity = false)
{
$this->_id = $id;
$this->_group = $group;
$data = false;
if ($this->_caching) {
$this->_setRefreshTime();
$this->_setFileName($id, $group);
clearstatcache();
if ($this->_memoryCaching) {
if (isset($this->_memoryCachingArray[$this->_file])) {
if ($this->_automaticSerialization) {
return unserialize($this->_memoryCachingArray[$this->_file]);
}
return $this->_memoryCachingArray[$this->_file];
}
if ($this->_onlyMemoryCaching) {
return false;
}
}
if(($doNotTestCacheValidity) || (is_null($this->_refreshTime))) {
if (file_exists($this->_file)) {
$data = $this->_read();
}
} else {
if ((file_exists($this->_file)) && (@filemtime($this->_file) > $this->_refreshTime)) {
$data = $this->_read();
}
}
if (($data) and ($this->_memoryCaching)) {
$this->_memoryCacheAdd($data);
}
if (($this->_automaticSerialization) and (is_string($data))) {
$data = unserialize($data);
}
return $data;
}
return false;
}
/**
* Save some data in a cache file
*
* @param string $data data to put in cache (can be another type than strings if automaticSerialization is on)
* @param string $id cache id
* @param string $group name of the cache group
* @return boolean true if no problem (else : false or a PEAR_Error object)
* @access public
*/
function save($data, $id = NULL, $group = 'default')
{
if ($this->_caching) {
if ($this->_automaticSerialization) {
$data = serialize($data);
}
if (isset($id)) {
$this->_setFileName($id, $group);
}
if ($this->_memoryCaching) {
$this->_memoryCacheAdd($data);
if ($this->_onlyMemoryCaching) {
return true;
}
}
if ($this->_automaticCleaningFactor>0) {
$rand = rand(1, $this->_automaticCleaningFactor);
if ($rand==1) {
$this->clean(false, 'old');
}
}
if ($this->_writeControl) {
$res = $this->_writeAndControl($data);
if (is_bool($res)) {
if ($res) {
return true;
}
// if $res if false, we need to invalidate the cache
@touch($this->_file, time() - 2*abs($this->_lifeTime));
return false;
}
} else {
$res = $this->_write($data);
}
if (is_object($res)) {
// $res is a PEAR_Error object
if (!($this->_errorHandlingAPIBreak)) {
return false; // we return false (old API)
}
}
return $res;
}
return false;
}

/**
* Remove a cache file
*
* @param string $id cache id
* @param string $group name of the cache group
* @return boolean true if no problem
* @access public
*/
function remove($id, $group = 'default')
{
$this->_setFileName($id, $group);
if ($this->_memoryCaching) {
if (isset($this->_memoryCachingArray[$this->_file])) {
unset($this->_memoryCachingArray[$this->_file]);
$this->_memoryCachingCounter = $this->_memoryCachingCounter - 1;
}
if ($this->_onlyMemoryCaching) {
return true;
}
}
return $this->_unlink($this->_file);
}

/**
* Clean the cache
*
* if no group is specified all cache files will be destroyed
* else only cache files of the specified group will be destroyed
*
* @param string $group name of the cache group
* @param string $mode flush cache mode : 'old', 'ingroup', 'notingroup',
* 'callback_myFunction'
* @return boolean true if no problem
* @access public
*/
function clean($group = false, $mode = 'ingroup')
{
return $this->_cleanDir($this->_cacheDir, $group, $mode);
}

/**
* Set to debug mode
*
* When an error is found, the script will stop and the message will be displayed
* (in debug mode only).
*
* @access public
*/
function setToDebug()
{
$this->setOption('pearErrorMode', CACHE_LITE_ERROR_DIE);
}

/**
* Set a new life time
*
* @param int $newLifeTime new life time (in seconds)
* @access public
*/
function setLifeTime($newLifeTime)
{
$this->_lifeTime = $newLifeTime;
$this->_setRefreshTime();
}

/**
* Save the state of the caching memory array into a cache file cache
*
* @param string $id cache id
* @param string $group name of the cache group
* @access public
*/
function saveMemoryCachingState($id, $group = 'default')
{
if ($this->_caching) {
$array = array(
'counter' => $this->_memoryCachingCounter,
'array' => $this->_memoryCachingState
);
$data = serialize($array);
$this->save($data, $id, $group);
}
}

/**
* Load the state of the caching memory array from a given cache file cache
*
* @param string $id cache id
* @param string $group name of the cache group
* @param boolean $doNotTestCacheValidity if set to true, the cache validity won't be tested
* @access public
*/
function getMemoryCachingState($id, $group = 'default', $doNotTestCacheValidity = false)
{
if ($this->_caching) {
if ($data = $this->get($id, $group, $doNotTestCacheValidity)) {
$array = unserialize($data);
$this->_memoryCachingCounter = $array['counter'];
$this->_memoryCachingArray = $array['array'];
}
}
}

/**
* Return the cache last modification time
*
* BE CAREFUL : THIS METHOD IS FOR HACKING ONLY !
*
* @return int last modification time
*/
function lastModified()
{
return @filemtime($this->_file);
}

/**
* Trigger a PEAR error
*
* To improve performances, the PEAR.php file is included dynamically.
* The file is so included only when an error is triggered. So, in most
* cases, the file isn't included and perfs are much better.
*
* @param string $msg error message
* @param int $code error code
* @access public
*/
function raiseError($msg, $code)
{
include_once('PEAR.php');
return PEAR::raiseError($msg, $code, $this->_pearErrorMode);
}

/**
* Extend the life of a valid cache file
*
* see http://pear.php.net/bugs/bug.php?id=6681
*
* @access public
*/
function extendLife()
{
@touch($this->_file);
}

// --- Private methods ---

/**
* Compute & set the refresh time
*
* @access private
*/
function _setRefreshTime()
{
if (is_null($this->_lifeTime)) {
$this->_refreshTime = null;
} else {
$this->_refreshTime = time() - $this->_lifeTime;
}
}

/**
* Remove a file
*
* @param string $file complete file path and name
* @return boolean true if no problem
* @access private
*/
function _unlink($file)
{
if (!@unlink($file)) {
return $this->raiseError('Cache_Lite : Unable to remove cache !', -3);
}
return true;
}

/**
* Recursive function for cleaning cache file in the given directory
*
* @param string $dir directory complete path (with a trailing slash)
* @param string $group name of the cache group
* @param string $mode flush cache mode : 'old', 'ingroup', 'notingroup',
'callback_myFunction'
* @return boolean true if no problem
* @access private
*/
function _cleanDir($dir, $group = false, $mode = 'ingroup')
{
if ($this->_fileNameProtection) {
$motif = ($group) ? 'cache_'.md5($group).'_' : 'cache_';
} else {
$motif = ($group) ? 'cache_'.$group.'_' : 'cache_';
}
if ($this->_memoryCaching) {
while (list($key, ) = each($this->_memoryCachingArray)) {
if (strpos($key, $motif, 0)) {
unset($this->_memoryCachingArray[$key]);
$this->_memoryCachingCounter = $this->_memoryCachingCounter - 1;
}
}
if ($this->_onlyMemoryCaching) {
return true;
}
}
if (!($dh = opendir($dir))) {
return $this->raiseError('Cache_Lite : Unable to open cache directory !', -4);
}
$result = true;
while ($file = readdir($dh)) {
if (($file != '.') && ($file != '..')) {
if (substr($file, 0, 6)=='cache_') {
$file2 = $dir . $file;
if (is_file($file2)) {
switch (substr($mode, 0, 9)) {
case 'old':
// files older than lifeTime get deleted from cache
if (!is_null($this->_lifeTime)) {
if ((mktime() - @filemtime($file2)) > $this->_lifeTime) {
$result = ($result and ($this->_unlink($file2)));
}
}
break;
case 'notingrou':
if (!strpos($file2, $motif, 0)) {
$result = ($result and ($this->_unlink($file2)));
}
break;
case 'callback_':
$func = substr($mode, 9, strlen($mode) - 9);
if ($func($file2, $group)) {
$result = ($result and ($this->_unlink($file2)));
}
break;
case 'ingroup':
default:
if (strpos($file2, $motif, 0)) {
$result = ($result and ($this->_unlink($file2)));
}
break;
}
}
if((is_dir($file2)) and ($this->_hashedDirectoryLevel>0)) {
$result = ($result and ($this->_cleanDir($file2 . '/', $group, $mode)));
}
}
}
}
return $result;
}

/**
* Add some date in the memory caching array
*
* @param string $data data to cache
* @access private
*/
function _memoryCacheAdd($data)
{
$this->_memoryCachingArray[$this->_file] = $data;
if ($this->_memoryCachingCounter >= $this->_memoryCachingLimit) {
list($key, ) = each($this->_memoryCachingArray);
unset($this->_memoryCachingArray[$key]);
} else {
$this->_memoryCachingCounter = $this->_memoryCachingCounter + 1;
}
}

/**
* Make a file name (with path)
*
* @param string $id cache id
* @param string $group name of the group
* @access private
*/
function _setFileName($id, $group)
{

if ($this->_fileNameProtection) {
$suffix = 'cache_'.md5($group).'_'.md5($id);
} else {
$suffix = 'cache_'.$group.'_'.$id;
}
$root = $this->_cacheDir;
if ($this->_hashedDirectoryLevel>0) {
$hash = md5($suffix);
for ($i=0 ; $i<$this->_hashedDirectoryLevel ; $i++) {
$root = $root . 'cache_' . substr($hash, 0, $i + 1) . '/';
}
}
$this->_fileName = $suffix;
$this->_file = $root.$suffix;
}

/**
* Read the cache file and return the content
*
* @return string content of the cache file (else : false or a PEAR_Error object)
* @access private
*/
function _read()
{
$fp = @fopen($this->_file, "rb");
if ($this->_fileLocking) @flock($fp, LOCK_SH);
if ($fp) {
clearstatcache();
$length = @filesize($this->_file);
$mqr = get_magic_quotes_runtime();
set_magic_quotes_runtime(0);
if ($this->_readControl) {
$hashControl = @fread($fp, 32);
$length = $length - 32;
}
if ($length) {
$data = @fread($fp, $length);
} else {
$data = '';
}
set_magic_quotes_runtime($mqr);
if ($this->_fileLocking) @flock($fp, LOCK_UN);
@fclose($fp);
if ($this->_readControl) {
$hashData = $this->_hash($data, $this->_readControlType);
if ($hashData != $hashControl) {
if (!(is_null($this->_lifeTime))) {
@touch($this->_file, time() - 2*abs($this->_lifeTime));
} else {
@unlink($this->_file);
}
return false;
}
}
return $data;
}
return $this->raiseError('Cache_Lite : Unable to read cache !', -2);
}

/**
* Write the given data in the cache file
*
* @param string $data data to put in cache
* @return boolean true if ok (a PEAR_Error object else)
* @access private
*/
function _write($data)
{
if ($this->_hashedDirectoryLevel > 0) {
$hash = md5($this->_fileName);
$root = $this->_cacheDir;
for ($i=0 ; $i<$this->_hashedDirectoryLevel ; $i++) {
$root = $root . 'cache_' . substr($hash, 0, $i + 1) . '/';
if (!(@is_dir($root))) {
@mkdir($root, $this->_hashedDirectoryUmask);
}
}
}
$fp = @fopen($this->_file, "wb");
if ($fp) {
if ($this->_fileLocking) @flock($fp, LOCK_EX);
if ($this->_readControl) {
@fwrite($fp, $this->_hash($data, $this->_readControlType), 32);
}
$len = strlen($data);
@fwrite($fp, $data, $len);
if ($this->_fileLocking) @flock($fp, LOCK_UN);
@fclose($fp);
return true;
}
return $this->raiseError('Cache_Lite : Unable to write cache file : '.$this->_file, -1);
}

/**
* Write the given data in the cache file and control it just after to avoir corrupted cache entries
*
* @param string $data data to put in cache
* @return boolean true if the test is ok (else : false or a PEAR_Error object)
* @access private
*/
function _writeAndControl($data)
{
$result = $this->_write($data);
if (is_object($result)) {
return $result; # We return the PEAR_Error object
}
$dataRead = $this->_read();
if (is_object($dataRead)) {
return $result; # We return the PEAR_Error object
}
if ((is_bool($dataRead)) && (!$dataRead)) {
return false;
}
return ($dataRead==$data);
}

/**
* Make a control key with the string containing datas
*
* @param string $data data
* @param string $controlType type of control 'md5', 'crc32' or 'strlen'
* @return string control key
* @access private
*/
function _hash($data, $controlType)
{
switch ($controlType) {
case 'md5':
return md5($data);
case 'crc32':
return sprintf('% 32d', crc32($data));
case 'strlen':
return sprintf('% 32d', strlen($data));
default:
return $this->raiseError('Unknown controlType ! (available values are only \'md5\', \'crc32\', \'strlen\')', -5);
}
}
}

Controller :

var $components = array ('MemCache');
var $ENABLE_CACHE =1;
var $ENABLE_CACHE_LOGGING =0;
function name()
{
$memcache = new Memcache;
$memcache->connect('localhost', 11211) or die ("Could not connect");
$memcache->addServer('64.237.62.50', 11211);
$memcache->addServer('64.237.62.51', 11211);
$this->Cache_Lite = array('cacheDir'=>$_SERVER['DOCUMENT_ROOT'].'/app/tmp', 'lifeTime'=>3600,'caching'=>'enable');

// code here
$cache_id = "_videolisting";
$this->MemCache->save(serialize($Userinfo),$cache_id,'Video');
if($this->ENABLE_CACHE==1)
{
if($cdat = $this->MemCache->get($cache_id,'Video'))
{
$cdat = unserialize($cdat);
$this->set('list',$list);
}
}else{
$this->set('list',$list);
}

}

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cakePHP Download Stable Version 1.1.19.6305

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cakePHP : Pagination

If part of your application includes displaying lots of results, it's a good idea to give the user the possibility to view the results in digestable chunks and possibly to be able to sort the presented data. This tutorial will explain how, after copying a few files into your application, you can achieve this in very few lines of code.
You need almost no knowledge of cake to be able to make use of this tutorial :).

If you already have a table in mind that you want to add pagination to, read on; otherwise run through http://manual.cakephp.org/appendix/blog_tutorial to have some code to play with.

Setting Up

All of the files necessary are available here in the bakery.

Save this file http://bakery.cakephp.org/articles/view/67 as /app/controllers/components/pagination.php

Save this file http://bakery.cakephp.org/articles/view/68 as /app/views/helpers/pagination.php

Save this file http://bakery.cakephp.org/articles/view/69 as /app/views/elements/pagination.thtml


Create/modify the Controller

The only change necessary to use pagination is to include the component, the helper and call the component method "init" before the relavent find.
Controller Class:


class PostsController extends AppController
{
var $name = 'Posts'; // for PHP4 installs
var $components = array ('Pagination'); // Added
var $helpers = array('Pagination'); // Added

function index() {
$criteria=NULL;
list($order,$limit,$page) = $this->Pagination->init($criteria); // Added
$data = $this->Post->findAll($criteria, NULL, $order, $limit, $page); // Extra parameters added

$this->set('data',$data);
}
}
?>

Create/modify the View



To make use of pagination, include the element, and optionally modify your table headers to allow changing the sort order of results:
View Template:

Paginated Posts Index

$pagination->setPaging($paging); // Initialize the pagination variables
$th = array (
$pagination->sortBy('id'),
$pagination->sortBy('title'),
$pagination->sortBy('created')
); // Generate the pagination sort links
echo $html->tableHeaders($th); // Create the table headers with sort links if desired

foreach ($data as $output)
{
$tr = array (
$output['Post']['id'],
$html->link($output['Post']['title'], "/Posts/View/{$output['Post']['id']}"),
$output['Post']['created']
);
echo $html->tableCells($tr,array('class'=>'altRow'),array('class'=>'evenRow'));
}
?>

renderElement('pagination'); // Render the pagination element ?>


Adding Ajax updates


If you include the RequestHandler component, the AJAX helper in your controller and the prototype js file is loaded in your view - you get your updates by ajax. Yes, it's that simple. The div that will be updated by default is the "content" div, you can change this by specifying in the component (either directly, or at run time) which div to update. And yes, you can disable this automatic behaviour if required.
How to add Prototype

So how do you add the prototype library..? Well...
Modify your layout

PHP Snippet:

The Prototype JavaScript library is availble at http://prototype.conio.net/
put prototype.js in /app/webroot/js/
Add the JavaScript code inside the head tag

if(isset($javascript)):
echo $javascript->link('prototype.js');
endif;
?>

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