<?php
/**
* This class extends Cache_Lite and can be used to cache the result and output of functions/methods
*
* This class is completly inspired from Sebastian Bergmann's
* PEAR/Cache_Function class. This is only an adaptation to
* Cache_Lite
*
* There are some examples in the 'docs/examples' file
* Technical choices are described in the 'docs/technical' file
*
* @package Cache_Lite
* @version $Id: Function.php,v 1.11 2006/12/14 12:59:43 cweiske Exp $
* @author Sebastian BERGMANN <[email protected]>
* @author Fabien MARTY <[email protected]>
*/
require_once('cacher/Lite.php');
class Cache_Lite_Function extends Cache_Lite
{
// --- Private properties ---
/**
* Default cache group for function caching
*
* @var string $_defaultGroup
*/
var $_defaultGroup = 'Cache_Lite_Function';
/**
* Don't cache the method call when its output contains the string "NOCACHE"
*
* if set to true, the output of the method will never be displayed (because the output is used
* to control the cache)
*
* @var boolean $_dontCacheWhenTheOutputContainsNOCACHE
*/
var $_dontCacheWhenTheOutputContainsNOCACHE = false;
/**
* Don't cache the method call when its result is false
*
* @var boolean $_dontCacheWhenTheResultIsFalse
*/
var $_dontCacheWhenTheResultIsFalse = false;
/**
* Don't cache the method call when its result is null
*
* @var boolean $_dontCacheWhenTheResultIsNull
*/
var $_dontCacheWhenTheResultIsNull = false;
/**
* Debug the Cache_Lite_Function caching process
*
* @var boolean $_debugCacheLiteFunction
*/
var $_debugCacheLiteFunction = false;
// --- Public methods ----
/**
* Constructor
*
* $options is an assoc. To have a look at availables options,
* see the constructor of the Cache_Lite class in 'Cache_Lite.php'
*
* Comparing to Cache_Lite constructor, there is another option :
* $options = array(
* (...) see Cache_Lite constructor
* 'debugCacheLiteFunction' => (bool) debug the caching process,
* 'defaultGroup' => default cache group for function caching (string),
* 'dontCacheWhenTheOutputContainsNOCACHE' => (bool) don't cache when the function output contains "NOCACHE",
* 'dontCacheWhenTheResultIsFalse' => (bool) don't cache when the function result is false,
* 'dontCacheWhenTheResultIsNull' => (bool don't cache when the function result is null
* );
*
* @param array $options options
* @access public
*/
function Cache_Lite_Function($options = array(NULL))
{
$availableOptions = array('debugCacheLiteFunction', 'defaultGroup', 'dontCacheWhenTheOutputContainsNOCACHE', 'dontCacheWhenTheResultIsFalse', 'dontCacheWhenTheResultIsNull');
while (list($name, $value) = each($options)) {
if (in_array($name, $availableOptions)) {
$property = '_'.$name;
$this->$property = $value;
}
}
reset($options);
$this->Cache_Lite($options);
}
/**
* Calls a cacheable function or method (or not if there is already a cache for it)
*
* Arguments of this method are read with func_get_args. So it doesn't appear
* in the function definition. Synopsis :
* call('functionName', $arg1, $arg2, ...)
* (arg1, arg2... are arguments of 'functionName')
*
* @return mixed result of the function/method
* @access public
*/
function call()
{
$arguments = func_get_args();
$id = $this->_makeId($arguments);
$data = $this->get($id, $this->_defaultGroup);
if ($data !== false) {
if ($this->_debugCacheLiteFunction) {
echo "Cache hit !\n";
}
$array = unserialize($data);
$output = $array['output'];
$result = $array['result'];
} else {
if ($this->_debugCacheLiteFunction) {
echo "Cache missed !\n";
}
ob_start();
ob_implicit_flush(false);
$target = array_shift($arguments);
if (is_array($target)) {
// in this case, $target is for example array($obj, 'method')
$object = $target[0];
$method = $target[1];
$result = call_user_func_array(array(&$object, $method), $arguments);
} else {
if (strstr($target, '::')) { // classname::staticMethod
list($class, $method) = explode('::', $target);
$result = call_user_func_array(array($class, $method), $arguments);
} else if (strstr($target, '->')) { // object->method
// use a stupid name ($objet_123456789 because) of problems where the object
// name is the same as this var name
list($object_123456789, $method) = explode('->', $target);
global $$object_123456789;
$result = call_user_func_array(array($$object_123456789, $method), $arguments);
} else { // function
$result = call_user_func_array($target, $arguments);
}
}
$output = ob_get_contents();
ob_end_clean();
if ($this->_dontCacheWhenTheResultIsFalse) {
if ((is_bool($result)) && (!($result))) {
echo($output);
return $result;
}
}
if ($this->_dontCacheWhenTheResultIsNull) {
if (is_null($result)) {
echo($output);
return $result;
}
}
if ($this->_dontCacheWhenTheOutputContainsNOCACHE) {
if (strpos($output, 'NOCACHE') > -1) {
return $result;
}
}
$array['output'] = $output;
$array['result'] = $result;
$this->save(serialize($array), $id, $this->_defaultGroup);
}
echo($output);
return $result;
}
/**
* Drop a cache file
*
* Arguments of this method are read with func_get_args. So it doesn't appear
* in the function definition. Synopsis :
* remove('functionName', $arg1, $arg2, ...)
* (arg1, arg2... are arguments of 'functionName')
*
* @return boolean true if no problem
* @access public
*/
function drop()
{
$id = $this->_makeId(func_get_args());
return $this->remove($id, $this->_defaultGroup);
}
/**
* Make an id for the cache
*
* @var array result of func_get_args for the call() or the remove() method
* @return string id
* @access private
*/
function _makeId($arguments)
{
$id = serialize($arguments); // Generate a cache id
if (!$this->_fileNameProtection) {
$id = md5($id);
// if fileNameProtection is set to false, then the id has to be hashed
// because it's a very bad file name in most cases
}
return $id;
}
}
?>