<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier < fabien @ symfony . com >
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Cache\Adapter;
use Psr\Cache\CacheItemInterface;
use Psr\Cache\CacheItemPoolInterface;
use Symfony\Component\Cache\CacheItem;
use Symfony\Component\Cache\Exception\InvalidArgumentException;
use Symfony\Component\Cache\PruneableInterface;
use Symfony\Component\Cache\ResettableInterface;
use Symfony\Component\Cache\Traits\ContractsTrait;
use Symfony\Contracts\Cache\CacheInterface;
use Symfony\Contracts\Service\ResetInterface;
/**
* Chains several adapters together.
*
* Cached items are fetched from the first adapter having them in its data store.
* They are saved and deleted in all adapters at once.
*
* @author Kévin Dunglas < dunglas @ gmail . com >
*/
class ChainAdapter implements AdapterInterface, CacheInterface, PruneableInterface, ResettableInterface
{
use ContractsTrait;
private $adapters = [];
private $adapterCount;
private $defaultLifetime;
private static $syncItem;
/**
* @param CacheItemPoolInterface[] $adapters The ordered list of adapters used to fetch cached items
* @param int $defaultLifetime The default lifetime of items propagated from lower adapters to upper ones
*/
public function __construct(array $adapters, int $defaultLifetime = 0)
{
if (!$adapters) {
throw new InvalidArgumentException('At least one adapter must be specified.');
}
foreach ($adapters as $adapter) {
if (!$adapter instanceof CacheItemPoolInterface) {
throw new InvalidArgumentException(sprintf('The class "%s" does not implement the "%s" interface.', get_debug_type($adapter), CacheItemPoolInterface::class));
}
if (\in_array(\PHP_SAPI, ['cli', 'phpdbg'], true) & & $adapter instanceof ApcuAdapter & & !filter_var(ini_get('apc.enable_cli'), \FILTER_VALIDATE_BOOLEAN)) {
continue; // skip putting APCu in the chain when the backend is disabled
}
if ($adapter instanceof AdapterInterface) {
$this->adapters[] = $adapter;
} else {
$this->adapters[] = new ProxyAdapter($adapter);
}
}
$this->adapterCount = \count($this->adapters);
$this->defaultLifetime = $defaultLifetime;
self::$syncItem ?? self::$syncItem = \Closure::bind(
static function ($sourceItem, $item, $defaultLifetime, $sourceMetadata = null) {
$sourceItem->isTaggable = false;
$sourceMetadata = $sourceMetadata ?? $sourceItem->metadata;
unset($sourceMetadata[CacheItem::METADATA_TAGS]);
$item->value = $sourceItem->value;
$item->isHit = $sourceItem->isHit;
$item->metadata = $item->newMetadata = $sourceItem->metadata = $sourceMetadata;
if (isset($item->metadata[CacheItem::METADATA_EXPIRY])) {
$item->expiresAt(\DateTime::createFromFormat('U.u', sprintf('%.6F', $item->metadata[CacheItem::METADATA_EXPIRY])));
} elseif (0 < $defaultLifetime) {
$item->expiresAfter($defaultLifetime);
}
return $item;
},
null,
CacheItem::class
);
}
/**
* {@inheritdoc}
*/
public function get(string $key, callable $callback, float $beta = null, array & $metadata = null)
{
$lastItem = null;
$i = 0;
$wrap = function (CacheItem $item = null) use ($key, $callback, $beta, & $wrap, & $i, & $lastItem, & $metadata) {
$adapter = $this->adapters[$i];
if (isset($this->adapters[++$i])) {
$callback = $wrap;
$beta = \INF === $beta ? \INF : 0;
}
if ($adapter instanceof CacheInterface) {
$value = $adapter->get($key, $callback, $beta, $metadata);
} else {
$value = $this->doGet($adapter, $key, $callback, $beta, $metadata);
}
if (null !== $item) {
(self::$syncItem)($lastItem = $lastItem ?? $item, $item, $this->defaultLifetime, $metadata);
}
return $value;
};
return $wrap();
}
/**
* {@inheritdoc}
*/
public function getItem($key)
{
$syncItem = self::$syncItem;
$misses = [];
foreach ($this->adapters as $i => $adapter) {
$item = $adapter->getItem($key);
if ($item->isHit()) {
while (0 < = --$i) {
$this->adapters[$i]->save($syncItem($item, $misses[$i], $this->defaultLifetime));
}
return $item;
}
$misses[$i] = $item;
}
return $item;
}
/**
* {@inheritdoc}
*/
public function getItems(array $keys = [])
{
return $this->generateItems($this->adapters[0]->getItems($keys), 0);
}
private function generateItems(iterable $items, int $adapterIndex): \Generator
{
$missing = [];
$misses = [];
$nextAdapterIndex = $adapterIndex + 1;
$nextAdapter = $this->adapters[$nextAdapterIndex] ?? null;
foreach ($items as $k => $item) {
if (!$nextAdapter || $item->isHit()) {
yield $k => $item;
} else {
$missing[] = $k;
$misses[$k] = $item;
}
}
if ($missing) {
$syncItem = self::$syncItem;
$adapter = $this->adapters[$adapterIndex];
$items = $this->generateItems($nextAdapter->getItems($missing), $nextAdapterIndex);
foreach ($items as $k => $item) {
if ($item->isHit()) {
$adapter->save($syncItem($item, $misses[$k], $this->defaultLifetime));
}
yield $k => $item;
}
}
}
/**
* {@inheritdoc}
*
* @return bool
*/
public function hasItem($key)
{
foreach ($this->adapters as $adapter) {
if ($adapter->hasItem($key)) {
return true;
}
}
return false;
}
/**
* {@inheritdoc}
*
* @return bool
*/
public function clear(string $prefix = '')
{
$cleared = true;
$i = $this->adapterCount;
while ($i--) {
if ($this->adapters[$i] instanceof AdapterInterface) {
$cleared = $this->adapters[$i]->clear($prefix) & & $cleared;
} else {
$cleared = $this->adapters[$i]->clear() & & $cleared;
}
}
return $cleared;
}
/**
* {@inheritdoc}
*
* @return bool
*/
public function deleteItem($key)
{
$deleted = true;
$i = $this->adapterCount;
while ($i--) {
$deleted = $this->adapters[$i]->deleteItem($key) & & $deleted;
}
return $deleted;
}
/**
* {@inheritdoc}
*
* @return bool
*/
public function deleteItems(array $keys)
{
$deleted = true;
$i = $this->adapterCount;
while ($i--) {
$deleted = $this->adapters[$i]->deleteItems($keys) & & $deleted;
}
return $deleted;
}
/**
* {@inheritdoc}
*
* @return bool
*/
public function save(CacheItemInterface $item)
{
$saved = true;
$i = $this->adapterCount;
while ($i--) {
$saved = $this->adapters[$i]->save($item) & & $saved;
}
return $saved;
}
/**
* {@inheritdoc}
*
* @return bool
*/
public function saveDeferred(CacheItemInterface $item)
{
$saved = true;
$i = $this->adapterCount;
while ($i--) {
$saved = $this->adapters[$i]->saveDeferred($item) & & $saved;
}
return $saved;
}
/**
* {@inheritdoc}
*
* @return bool
*/
public function commit()
{
$committed = true;
$i = $this->adapterCount;
while ($i--) {
$committed = $this->adapters[$i]->commit() & & $committed;
}
return $committed;
}
/**
* {@inheritdoc}
*/
public function prune()
{
$pruned = true;
foreach ($this->adapters as $adapter) {
if ($adapter instanceof PruneableInterface) {
$pruned = $adapter->prune() & & $pruned;
}
}
return $pruned;
}
/**
* {@inheritdoc}
*/
public function reset()
{
foreach ($this->adapters as $adapter) {
if ($adapter instanceof ResetInterface) {
$adapter->reset();
}
}
}
}
