<?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\Log\LoggerAwareInterface;
use Symfony\Component\Cache\CacheItem;
use Symfony\Component\Cache\Exception\InvalidArgumentException;
use Symfony\Component\Cache\ResettableInterface;
use Symfony\Component\Cache\Traits\AbstractAdapterTrait;
use Symfony\Component\Cache\Traits\ContractsTrait;
use Symfony\Contracts\Cache\TagAwareCacheInterface;
/**
* Abstract for native TagAware adapters.
*
* To keep info on tags, the tags are both serialized as part of cache value and provided as tag ids
* to Adapters on operations when needed for storage to doSave(), doDelete() & doInvalidate().
*
* @author Nicolas Grekas <p@tchwork.com>
* @author André Rømcke <andre.romcke+symfony@gmail.com>
*
* @internal
* @experimental in 4.3
*/
abstract class AbstractTagAwareAdapter implements TagAwareAdapterInterface, TagAwareCacheInterface, LoggerAwareInterface, ResettableInterface
{
use AbstractAdapterTrait;
use ContractsTrait;
private const TAGS_PREFIX = "\0tags\0";
protected function __construct(string $namespace = '', int $defaultLifetime = 0)
{
$this->namespace = '' === $namespace ? '' : CacheItem::validateKey($namespace).':';
if (null !== $this->maxIdLength && \strlen($namespace) > $this->maxIdLength - 24) {
throw new InvalidArgumentException(sprintf('Namespace must be %d chars max, %d given ("%s")', $this->maxIdLength - 24, \strlen($namespace), $namespace));
}
$this->createCacheItem = \Closure::bind(
static function ($key, $value, $isHit) use ($defaultLifetime) {
$item = new CacheItem();
$item->key = $key;
$item->defaultLifetime = $defaultLifetime;
$item->isTaggable = true;
// If structure does not match what we expect return item as is (no value and not a hit)
if (!\is_array($value) || !\array_key_exists('value', $value)) {
return $item;
}
$item->isHit = $isHit;
// Extract value, tags and meta data from the cache value
$item->value = $value['value'];
$item->metadata[CacheItem::METADATA_TAGS] = $value['tags'] ?? [];
if (isset($value['meta'])) {
// For compactness these values are packed, & expiry is offset to reduce size
$v = unpack('Ve/Nc', $value['meta']);
$item->metadata[CacheItem::METADATA_EXPIRY] = $v['e'] + CacheItem::METADATA_EXPIRY_OFFSET;
$item->metadata[CacheItem::METADATA_CTIME] = $v['c'];
}
return $item;
},
null,
CacheItem::class
);
$getId = \Closure::fromCallable([$this, 'getId']);
$tagPrefix = self::TAGS_PREFIX;
$this->mergeByLifetime = \Closure::bind(
static function ($deferred, &$expiredIds) use ($getId, $tagPrefix) {
$byLifetime = [];
$now = microtime(true);
$expiredIds = [];
foreach ($deferred as $key => $item) {
$key = (string) $key;
if (null === $item->expiry) {
$ttl = 0 < $item->defaultLifetime ? $item->defaultLifetime : 0;
} elseif (0 >= $ttl = (int) (0.1 + $item->expiry - $now)) {
$expiredIds[] = $getId($key);
continue;
}
// Store Value and Tags on the cache value
if (isset(($metadata = $item->newMetadata)[CacheItem::METADATA_TAGS])) {
$value = ['value' => $item->value, 'tags' => $metadata[CacheItem::METADATA_TAGS]];
unset($metadata[CacheItem::METADATA_TAGS]);
} else {
$value = ['value' => $item->value, 'tags' => []];
}
if ($metadata) {
// For compactness, expiry and creation duration are packed, using magic numbers as separators
$value['meta'] = pack('VN', (int) (0.1 + $metadata[self::METADATA_EXPIRY] - self::METADATA_EXPIRY_OFFSET), $metadata[self::METADATA_CTIME]);
}
// Extract tag changes, these should be removed from values in doSave()
$value['tag-operations'] = ['add' => [], 'remove' => []];
$oldTags = $item->metadata[CacheItem::METADATA_TAGS] ?? [];
foreach (array_diff($value['tags'], $oldTags) as $addedTag) {
$value['tag-operations']['add'][] = $getId($tagPrefix.$addedTag);
}
foreach (array_diff($oldTags, $value['tags']) as $removedTag) {
$value['tag-operations']['remove'][] = $getId($tagPrefix.$removedTag);
}
$byLifetime[$ttl][$getId($key)] = $value;
}
return $byLifetime;
},
null,
CacheItem::class
);
}
/**
* Persists several cache items immediately.
*
* @param array $values The values to cache, indexed by their cache identifier
* @param int $lifetime The lifetime of the cached values, 0 for persisting until manual cleaning
* @param array[] $addTagData Hash where key is tag id, and array value is list of cache id's to add to tag
* @param array[] $removeTagData Hash where key is tag id, and array value is list of cache id's to remove to tag
*
* @return array The identifiers that failed to be cached or a boolean stating if caching succeeded or not
*/
abstract protected function doSave(array $values, ?int $lifetime, array $addTagData = [], array $removeTagData = []): array;
/**
* Removes multiple items from the pool and their corresponding tags.
*
* @param array $ids An array of identifiers that should be removed from the pool
* @param array $tagData Optional array of tag identifiers => key identifiers that should be removed from the pool
*
* @return bool True if the items were successfully removed, false otherwise
*/
abstract protected function doDelete(array $ids, array $tagData = []): bool;
/**
* Invalidates cached items using tags.
*
* @param string[] $tagIds An array of tags to invalidate, key is tag and value is tag id
*
* @return bool True on success
*/
abstract protected function doInvalidate(array $tagIds): bool;
/**
* {@inheritdoc}
*/
public function commit()
{
$ok = true;
$byLifetime = $this->mergeByLifetime;
$byLifetime = $byLifetime($this->deferred, $expiredIds);
$retry = $this->deferred = [];
if ($expiredIds) {
// Tags are not cleaned up in this case, however that is done on invalidateTags().
$this->doDelete($expiredIds);
}
foreach ($byLifetime as $lifetime => $values) {
try {
$values = $this->extractTagData($values, $addTagData, $removeTagData);
$e = $this->doSave($values, $lifetime, $addTagData, $removeTagData);
} catch (\Exception $e) {
}
if (true === $e || [] === $e) {
continue;
}
if (\is_array($e) || 1 === \count($values)) {
foreach (\is_array($e) ? $e : array_keys($values) as $id) {
$ok = false;
$v = $values[$id];
$type = \is_object($v) ? \get_class($v) : \gettype($v);
$message = sprintf('Failed to save key "{key}" of type %s%s', $type, $e instanceof \Exception ? ': '.$e->getMessage() : '.');
CacheItem::log($this->logger, $message, ['key' => substr($id, \strlen($this->namespace)), 'exception' => $e instanceof \Exception ? $e : null]);
}
} else {
foreach ($values as $id => $v) {
$retry[$lifetime][] = $id;
}
}
}
// When bulk-save failed, retry each item individually
foreach ($retry as $lifetime => $ids) {
foreach ($ids as $id) {
try {
$v = $byLifetime[$lifetime][$id];
$values = $this->extractTagData([$id => $v], $addTagData, $removeTagData);
$e = $this->doSave($values, $lifetime, $addTagData, $removeTagData);
} catch (\Exception $e) {
}
if (true === $e || [] === $e) {
continue;
}
$ok = false;
$type = \is_object($v) ? \get_class($v) : \gettype($v);
$message = sprintf('Failed to save key "{key}" of type %s%s', $type, $e instanceof \Exception ? ': '.$e->getMessage() : '.');
CacheItem::log($this->logger, $message, ['key' => substr($id, \strlen($this->namespace)), 'exception' => $e instanceof \Exception ? $e : null]);
}
}
return $ok;
}
/**
* {@inheritdoc}
*
* Overloaded in order to deal with tags for adjusted doDelete() signature.
*/
public function deleteItems(array $keys)
{
if (!$keys) {
return true;
}
$ids = [];
$tagData = [];
foreach ($keys as $key) {
$ids[$key] = $this->getId($key);
unset($this->deferred[$key]);
}
try {
foreach ($this->doFetch($ids) as $id => $value) {
foreach ($value['tags'] ?? [] as $tag) {
$tagData[$this->getId(self::TAGS_PREFIX.$tag)][] = $id;
}
}
} catch (\Exception $e) {
// ignore unserialization failures
}
try {
if ($this->doDelete(array_values($ids), $tagData)) {
return true;
}
} catch (\Exception $e) {
}
$ok = true;
// When bulk-delete failed, retry each item individually
foreach ($ids as $key => $id) {
try {
$e = null;
if ($this->doDelete([$id])) {
continue;
}
} catch (\Exception $e) {
}
$message = 'Failed to delete key "{key}"'.($e instanceof \Exception ? ': '.$e->getMessage() : '.');
CacheItem::log($this->logger, $message, ['key' => $key, 'exception' => $e]);
$ok = false;
}
return $ok;
}
/**
* {@inheritdoc}
*/
public function invalidateTags(array $tags)
{
if (empty($tags)) {
return false;
}
$tagIds = [];
foreach (array_unique($tags) as $tag) {
$tagIds[] = $this->getId(self::TAGS_PREFIX.$tag);
}
if ($this->doInvalidate($tagIds)) {
return true;
}
return false;
}
/**
* Extracts tags operation data from $values set in mergeByLifetime, and returns values without it.
*/
private function extractTagData(array $values, ?array &$addTagData, ?array &$removeTagData): array
{
$addTagData = $removeTagData = [];
foreach ($values as $id => $value) {
foreach ($value['tag-operations']['add'] as $tag => $tagId) {
$addTagData[$tagId][] = $id;
}
foreach ($value['tag-operations']['remove'] as $tag => $tagId) {
$removeTagData[$tagId][] = $id;
}
unset($values[$id]['tag-operations']);
}
return $values;
}
}