<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <[email protected]>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Contracts\Cache;
use Psr\Cache\CacheItemInterface;
use Psr\Cache\InvalidArgumentException;
/**
* Covers most simple to advanced caching needs.
*
* @author Nicolas Grekas <[email protected]>
*/
interface CacheInterface
{
/**
* Fetches a value from the pool or computes it if not found.
*
* On cache misses, a callback is called that should return the missing value.
* This callback is given a PSR-6 CacheItemInterface instance corresponding to the
* requested key, that could be used e.g. for expiration control. It could also
* be an ItemInterface instance when its additional features are needed.
*
* @param string $key The key of the item to retrieve from the cache
* @param callable|CallbackInterface $callback Should return the computed value for the given key/item
* @param float|null $beta A float that, as it grows, controls the likeliness of triggering
* early expiration. 0 disables it, INF forces immediate expiration.
* The default (or providing null) is implementation dependent but should
* typically be 1.0, which should provide optimal stampede protection.
* See https://en.wikipedia.org/wiki/Cache_stampede#Probabilistic_early_expiration
* @param array &$metadata The metadata of the cached item {@see ItemInterface::getMetadata()}
*
* @return mixed The value corresponding to the provided key
*
* @throws InvalidArgumentException When $key is not valid or when $beta is negative
*/
public function get(string $key, callable $callback, float $beta = null, array &$metadata = null);
/**
* Removes an item from the pool.
*
* @param string $key The key to delete
*
* @throws InvalidArgumentException When $key is not valid
*
* @return bool True if the item was successfully removed, false if there was any error
*/
public function delete(string $key): bool;
}