Magento cache example

Here is an example of using Magento’s cache feature. It stores the data in a cache and respond with the cached data if the data is already cached. The cache can be removed if the param clean=yes. Install this example by creating these three files in the appropriate directory. Then go to the url http://localhost/magecacheexample?id=2, to clean the cached version of the data, go to the url http://localhost/magecacheexample?id=2&clean=yes. If the entire caches from var/cache/ are all cleared, this cache will also be cleared.

1. Module install configuration, app/etc/modules/MyExtensions_MageCacheExample.xml
[code language=”xml”]
<?xml version="1.0"?>
<config>
<modules>
<MyExtensions_MageCacheExample>
<active>true</active>
<codePool>local</codePool>
</MyExtensions_MageCacheExample>
</modules>
</config>
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2. Module configuration, app/code/local/MyExtensions/MageCacheExample/etc/config.xml
[code language=”xml”]
<?xml version="1.0"?>
<config>
<modules>
<MyExtensions_MageCacheExample>
<version>0.1.0</version>
</MyExtensions_MageCacheExample>
</modules>
<frontend>
<routers>
<magecacheexample>
<use>standard</use>
<args>
<module>MyExtensions_MageCacheExample</module>
<frontName>magecacheexample</frontName>
</args>
</magecacheexample>
</routers>
</frontend>
</config>
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3. Index controller, app/code/local/MyExtensions/MageCacheExample/controllers/indexController.php
[code language=”php”]
<?php
class MyExtensions_MageCacheExample_IndexController extends Mage_Core_Controller_Front_Action {

const CACHE_KEY_PREFIX = ‘cacheEx’;

//Main action
//if the param id is null, respond with {message:"Please provide an id."}
//if the id is not null, and the data is already stored in the cache, respond with the data from cache.
//if the id is not null, and the data is not yet cache, create the data, save it to the cache and then respond with the data.
public function indexAction() {

$this->getResponse()->setHeader(‘Content-type’, ‘application/json’);
$id = $this->getRequest()->getParam(‘id’);
$clean = $this->getRequest()->getParam(‘clean’);
$cache = Mage::app()->getCache();
$data;

if( !is_null($id) )
{

if($clean === "yes")
{
$cache->remove( self::CACHE_KEY_PREFIX . $id );
}

$data = $cache->load( self::CACHE_KEY_PREFIX . $id );
//get the data from cache if it’s cached, else create the data and save it to the cache
if ( $data !== false )
{
echo "cached";
$this->getResponse()->setBody( $data );
}
else
{
$data = $this->createDummyData();
$cache->save( $data, self::CACHE_KEY_PREFIX . $id, array(‘mage_cache_example’), 60*60*24*30); //set the cache for 30 days
echo "not cached";
$this->getResponse()->setBody( $data );

}
}
else
{
$this->getResponse()->setBody( ‘{message:"Please provide an id."}’ );
}

}

private function createDummyData() {
$arr = array();
for($i=0; $i<100; $i++)
{
for($j=0; $j<8000; $j++)
{
$arr["top".$i][] = "second" . $j;
}
}

return json_encode($arr);
}

}
[/code]