proxy_cache.md

Proxy cache

---

Common bundle can add all proxy cache headers with specified TTLs and xKeys. It also adds system specific xKey automatically to enable purging the cache for the whole system.

---

Usage

Create a class that extends AnzuSystems\Contracts\Response\Cache\AbstractCacheSettings and set TTL:

final class ExampleCacheSettings extends AbstractCacheSettings
{
    public function __construct() {
        parent::__construct(60);
    }
}  

Then simply pass it to the okResponse() function available in controller:

public function getSomeInfo(): JsonResponse
{
    return $this->okResponse($someInfo, new ExampleCacheSettings());
}

Custom xKey

If you want to add a custom xKey, just override the getXkeys() function and add all desired xKeys:

protected function getXKeys(): array
{
    return [
        'custom_xKey',
    ];
}

Dynamic xKey

If you are planning to generate xKeys based on some object/entity, override the buildXKeyFromObject() function. This will also provide you with a static helper function later on (see cache purging below).

final class ExamplePostCacheSettings extends AbstractCacheSettings
{
    public const XKEY_PREFIX = 'post';

    public function __construct(
        private Post $post,
    ) {
        parent::__construct(60);
    }

    public static function buildXKeyFromObject(object $data): string
    {
        if ($data instanceof Post) {
            return self::XKEY_PREFIX . '-' . ((string) $data->getId());
        }

        return self::XKEY_PREFIX;
    }

    protected function getXKeys(): array
    {
        return [
            self::buildXKeyFromObject($this->post),
        ];
    }
}

Then use it in controller like this:

public function getSomeInfoAboutPost(Post $post): JsonResponse
{
    return $this->okResponse($someInfoAboutPost, new ExamplePostCacheSettings($post));
}

Purging cache by xKey:

You can always retrieve the correct xKey (i.e. if you are planning to purge cache by xKey):

// xkey for whole system: 
ExampleCacheSettings::getSystemXkey();

// xkey for a particular post:
ExamplePostCacheSettings::buildXKeyFromObject($post);