class MemoryBackend

Same name in this branch
  1. 11.x core/lib/Drupal/Core/Flood/MemoryBackend.php \Drupal\Core\Flood\MemoryBackend
Same name in other branches
  1. 9 core/lib/Drupal/Core/Flood/MemoryBackend.php \Drupal\Core\Flood\MemoryBackend
  2. 9 core/lib/Drupal/Core/Cache/MemoryBackend.php \Drupal\Core\Cache\MemoryBackend
  3. 8.9.x core/lib/Drupal/Core/Flood/MemoryBackend.php \Drupal\Core\Flood\MemoryBackend
  4. 8.9.x core/lib/Drupal/Core/Cache/MemoryBackend.php \Drupal\Core\Cache\MemoryBackend
  5. 10 core/lib/Drupal/Core/Flood/MemoryBackend.php \Drupal\Core\Flood\MemoryBackend
  6. 10 core/lib/Drupal/Core/Cache/MemoryBackend.php \Drupal\Core\Cache\MemoryBackend

Defines a memory cache implementation.

Stores cache items in memory using a PHP array.

Should be used for unit tests and specialist use-cases only, does not store cached items between requests.

The functions ::prepareItem()/::set() use unserialize()/serialize(). It behaves as an external cache backend to avoid changing the cached data by reference. In ::prepareItem(), the object is not modified by the call to unserialize() because we make a clone of it.

Hierarchy

Expanded class hierarchy of MemoryBackend

Related topics

14 files declare their use of MemoryBackend
AssetResolverTest.php in core/tests/Drupal/Tests/Core/Asset/AssetResolverTest.php
BackendChainImplementationUnitTest.php in core/tests/Drupal/Tests/Core/Cache/BackendChainImplementationUnitTest.php
BackendChainTest.php in core/tests/Drupal/KernelTests/Core/Cache/BackendChainTest.php
CacheFactoryDecorator.php in core/modules/system/tests/modules/performance_test/src/Cache/CacheFactoryDecorator.php
ChainedFastBackendTest.php in core/tests/Drupal/Tests/Core/Cache/ChainedFastBackendTest.php

... See full list

File

core/lib/Drupal/Core/Cache/MemoryBackend.php, line 23

Namespace

Drupal\Core\Cache
View source
class MemoryBackend implements CacheBackendInterface, CacheTagsInvalidatorInterface {
    
    /**
     * Array to store cache objects.
     *
     * @var object[]
     */
    protected $cache = [];
    
    /**
     * Constructs a MemoryBackend object.
     *
     * @param \Drupal\Component\Datetime\TimeInterface $time
     *   The time service.
     */
    public function __construct(TimeInterface $time) {
    }
    
    /**
     * {@inheritdoc}
     */
    public function get($cid, $allow_invalid = FALSE) {
        if (isset($this->cache[$cid])) {
            return $this->prepareItem($this->cache[$cid], $allow_invalid);
        }
        else {
            return FALSE;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function getMultiple(&$cids, $allow_invalid = FALSE) {
        $ret = [];
        $items = array_intersect_key($this->cache, array_flip($cids));
        foreach ($items as $item) {
            $item = $this->prepareItem($item, $allow_invalid);
            if ($item) {
                $ret[$item->cid] = $item;
            }
        }
        $cids = array_diff($cids, array_keys($ret));
        return $ret;
    }
    
    /**
     * Prepares a cached item.
     *
     * Checks that items are either permanent or did not expire, and returns data
     * as appropriate.
     *
     * @param object $cache
     *   An item loaded from self::get() or self::getMultiple().
     * @param bool $allow_invalid
     *   (optional) If TRUE, cache items may be returned even if they have expired
     *   or been invalidated.
     *
     * @return mixed
     *   The item with data as appropriate or FALSE if there is no
     *   valid item to load.
     */
    protected function prepareItem($cache, $allow_invalid) {
        if (!isset($cache->data)) {
            return FALSE;
        }
        // The object passed into this function is the one stored in $this->cache.
        // We must clone it as part of the preparation step so that the actual
        // cache object is not affected by the unserialize() call or other
        // manipulations of the returned object.
        $prepared = clone $cache;
        $prepared->data = unserialize($prepared->data);
        // Check expire time.
        $prepared->valid = $prepared->expire == Cache::PERMANENT || $prepared->expire >= $this->time
            ->getRequestTime();
        if (!$allow_invalid && !$prepared->valid) {
            return FALSE;
        }
        return $prepared;
    }
    
    /**
     * {@inheritdoc}
     */
    public function set($cid, $data, $expire = Cache::PERMANENT, array $tags = []) {
        assert(Inspector::assertAllStrings($tags), 'Cache Tags must be strings.');
        $tags = array_unique($tags);
        // Sort the cache tags so that they are stored consistently in the database.
        sort($tags);
        $this->cache[$cid] = (object) [
            'cid' => $cid,
            'data' => serialize($data),
            'created' => $this->time
                ->getRequestTime(),
            'expire' => $expire,
            'tags' => $tags,
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function setMultiple(array $items = []) {
        foreach ($items as $cid => $item) {
            $this->set($cid, $item['data'], $item['expire'] ?? CacheBackendInterface::CACHE_PERMANENT, $item['tags'] ?? []);
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function delete($cid) {
        unset($this->cache[$cid]);
    }
    
    /**
     * {@inheritdoc}
     */
    public function deleteMultiple(array $cids) {
        $this->cache = array_diff_key($this->cache, array_flip($cids));
    }
    
    /**
     * {@inheritdoc}
     */
    public function deleteAll() {
        $this->cache = [];
    }
    
    /**
     * {@inheritdoc}
     */
    public function invalidate($cid) {
        if (isset($this->cache[$cid])) {
            $this->cache[$cid]->expire = $this->time
                ->getRequestTime() - 1;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function invalidateMultiple(array $cids) {
        $items = array_intersect_key($this->cache, array_flip($cids));
        foreach ($items as $cid => $item) {
            $this->cache[$cid]->expire = $this->time
                ->getRequestTime() - 1;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function invalidateTags(array $tags) {
        foreach ($this->cache as $cid => $item) {
            if (array_intersect($tags, $item->tags)) {
                $this->cache[$cid]->expire = $this->time
                    ->getRequestTime() - 1;
            }
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function invalidateAll() {
        foreach ($this->cache as $cid => $item) {
            $this->cache[$cid]->expire = $this->time
                ->getRequestTime() - 1;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function garbageCollection() {
    }
    
    /**
     * {@inheritdoc}
     */
    public function removeBin() {
        $this->cache = [];
    }
    
    /**
     * Prevents data stored in memory backends from being serialized.
     */
    public function __sleep() : array {
        return [
            'time',
        ];
    }
    
    /**
     * Reset statically cached variables.
     *
     * This is only used by tests.
     */
    public function reset() {
        $this->cache = [];
    }

}

Members

Title Sort descending Modifiers Object type Summary Overriden Title Overrides
CacheBackendInterface::CACHE_PERMANENT constant Indicates that the item should never be removed unless explicitly deleted.
MemoryBackend::$cache protected property Array to store cache objects.
MemoryBackend::delete public function Deletes an item from the cache. Overrides CacheBackendInterface::delete 1
MemoryBackend::deleteAll public function Deletes all cache items in a bin. Overrides CacheBackendInterface::deleteAll
MemoryBackend::deleteMultiple public function Deletes multiple items from the cache. Overrides CacheBackendInterface::deleteMultiple
MemoryBackend::garbageCollection public function Performs garbage collection on a cache bin. Overrides CacheBackendInterface::garbageCollection
MemoryBackend::get public function Returns data from the persistent cache. Overrides CacheBackendInterface::get 1
MemoryBackend::getMultiple public function Returns data from the persistent cache when given an array of cache IDs. Overrides CacheBackendInterface::getMultiple
MemoryBackend::invalidate public function Marks a cache item as invalid. Overrides CacheBackendInterface::invalidate
MemoryBackend::invalidateAll public function Marks all cache items as invalid. Overrides CacheBackendInterface::invalidateAll
MemoryBackend::invalidateMultiple public function Marks cache items as invalid. Overrides CacheBackendInterface::invalidateMultiple
MemoryBackend::invalidateTags public function Marks cache items with any of the specified tags as invalid. Overrides CacheTagsInvalidatorInterface::invalidateTags
MemoryBackend::prepareItem protected function Prepares a cached item. 1
MemoryBackend::removeBin public function Remove a cache bin. Overrides CacheBackendInterface::removeBin
MemoryBackend::reset public function Reset statically cached variables.
MemoryBackend::set public function Stores data in the persistent cache. Overrides CacheBackendInterface::set 2
MemoryBackend::setMultiple public function Store multiple items in the persistent cache. Overrides CacheBackendInterface::setMultiple
MemoryBackend::__construct public function Constructs a MemoryBackend object.
MemoryBackend::__sleep public function Prevents data stored in memory backends from being serialized.

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