* * 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 */ 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) { $doSave = true; $callback = static function (CacheItem $item, bool &$save) use ($callback, &$doSave) { $value = $callback($item, $save); $doSave = $save; return $value; }; $lastItem = null; $i = 0; $wrap = function (?CacheItem $item = null, bool &$save = true) use ($key, $callback, $beta, &$wrap, &$i, &$doSave, &$lastItem, &$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); } $save = $doSave; 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(); } } } }