Using Cache service

Using the internal cache service allows you to use an inter= face and to not have to care whether the system has been configured to plac= e the cache in Memcached or on File system. And as eZ Platform requires tha= t instances use a cluster-aware cache in Cluster setup, you can safely assu= me your cache is shared (and invalidated) across all web= servers.

Interface will change in the future

Current implementation uses a caching library called Stash, = via StashBundle. We plan to move to a P= SR-6 compatible cache service capable of supporting cache Tagging and multi= get/set in the future, when that happens the interface of the cache servic= e will change!

Use unique vendor prefix for Cache key!

When reusing the cache service within your own code, it is very importan= t to not conflict with the cache keys used by others. That is why the examp= le of usage below starts with a unique "myApp" key. For the namespace of yo= ur own cache, you must do the same! So never clear cache using the cache se= rvice without your key specified, otherwise you'll clear all cache.

Get Cache service

Via Dependency injectio= n

In your Symfony services configuration you can simply define that you re= quire the "cache" service in your configuration like so:

yml configuration

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    myApp.myService:
        class: %myApp.myService.class%
        arguments:
            - @ezpublish.cache_pool

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The "cache" service is an instance of the following class: Te= divm\StashBundle\Service\CacheService

Via Symfony Container

Like any other service, it is also possible to get the "cache" service v= ia container like so:

Getting the cache service in PHP

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/** @var $cacheService \Tedivm\StashBundle\Service\CacheService */
$cacheService =3D $container->get('ezpublish.cache_pool');

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Using the cache service

Example usage of the cache service:

Example

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    $cacheItem =3D $cacheService->getItem('myApp', 'object', $id=
);
    $myObject =3D $cacheItem->get();
    if ($cacheItem->isMiss()) {
        $myObject =3D $container->get('my_app.backend_service')->load=
Object($id)
        $cacheItem->set($myObject);
    }
    return $myObject;

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For more info on usage, take a look at Stash's documentation= .

Clearing Persistence = cache

Persistence cache uses a separate Cache Pool decorator which by design p= refixes cache keys with "ez_spi= ". Clearing persistence cache can thus be done in the following way:

getting the cache service in php

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/** @var $cacheService \eZ\Publish\Core\Persistence\Cache\CacheServ=
iceDecorator */
$cacheService =3D $container->get('ezpublish.cache_pool.spi.cache.decora=
tor');
 
// To clear all cache
$cacheService->clear();
 
// To clear a specific cache item (check source code in eZ\Publish\Core\Per=
sistence\Cache\*Handlers for further info)
$cacheService->clear('content', 'info', $contentId);

// Stash cache is hierarchical, so you can clear all content/info cache lik=
e so:
$cacheService->clear('content', 'info');

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