Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\Core\Cache;
Chris@0: 
Chris@14: use Drupal\Component\Assertion\Inspector;
Chris@0: use Drupal\Core\PhpStorage\PhpStorageFactory;
Chris@0: use Drupal\Component\Utility\Crypt;
Chris@0: 
Chris@0: /**
Chris@0:  * Defines a PHP cache implementation.
Chris@0:  *
Chris@0:  * Stores cache items in a PHP file using a storage that implements
Chris@0:  * Drupal\Component\PhpStorage\PhpStorageInterface.
Chris@0:  *
Chris@0:  * This is fast because of PHP's opcode caching mechanism. Once a file's
Chris@0:  * content is stored in PHP's opcode cache, including it doesn't require
Chris@0:  * reading the contents from a filesystem. Instead, PHP will use the already
Chris@0:  * compiled opcodes stored in memory.
Chris@0:  *
Chris@0:  * @ingroup cache
Chris@0:  */
Chris@0: class PhpBackend implements CacheBackendInterface {
Chris@0: 
Chris@0:   /**
Chris@0:    * @var string
Chris@0:    */
Chris@0:   protected $bin;
Chris@0: 
Chris@0:   /**
Chris@0:    * Array to store cache objects.
Chris@0:    */
Chris@0:   protected $cache = [];
Chris@0: 
Chris@0:   /**
Chris@0:    * The cache tags checksum provider.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Cache\CacheTagsChecksumInterface
Chris@0:    */
Chris@0:   protected $checksumProvider;
Chris@0: 
Chris@0:   /**
Chris@0:    * Constructs a PhpBackend object.
Chris@0:    *
Chris@0:    * @param string $bin
Chris@0:    *   The cache bin for which the object is created.
Chris@0:    * @param \Drupal\Core\Cache\CacheTagsChecksumInterface $checksum_provider
Chris@0:    *   The cache tags checksum provider.
Chris@0:    */
Chris@0:   public function __construct($bin, CacheTagsChecksumInterface $checksum_provider) {
Chris@0:     $this->bin = 'cache_' . $bin;
Chris@0:     $this->checksumProvider = $checksum_provider;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function get($cid, $allow_invalid = FALSE) {
Chris@0:     return $this->getByHash($this->normalizeCid($cid), $allow_invalid);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Fetch a cache item using a hashed cache ID.
Chris@0:    *
Chris@0:    * @param string $cidhash
Chris@0:    *   The hashed version of the original cache ID after being normalized.
Chris@0:    * @param bool $allow_invalid
Chris@0:    *   (optional) If TRUE, a cache item may be returned even if it is expired or
Chris@0:    *   has been invalidated.
Chris@0:    *
Chris@0:    * @return bool|mixed
Chris@0:    */
Chris@0:   protected function getByHash($cidhash, $allow_invalid = FALSE) {
Chris@0:     if ($file = $this->storage()->getFullPath($cidhash)) {
Chris@0:       $cache = @include $file;
Chris@0:     }
Chris@0:     if (isset($cache)) {
Chris@0:       return $this->prepareItem($cache, $allow_invalid);
Chris@0:     }
Chris@0:     return FALSE;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function setMultiple(array $items) {
Chris@0:     foreach ($items as $cid => $item) {
Chris@0:       $this->set($cid, $item['data'], isset($item['expire']) ? $item['expire'] : CacheBackendInterface::CACHE_PERMANENT, isset($item['tags']) ? $item['tags'] : []);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getMultiple(&$cids, $allow_invalid = FALSE) {
Chris@0:     $ret = [];
Chris@0: 
Chris@0:     foreach ($cids as $cid) {
Chris@0:       if ($item = $this->get($cid, $allow_invalid)) {
Chris@0:         $ret[$item->cid] = $item;
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     $cids = array_diff($cids, array_keys($ret));
Chris@0: 
Chris@0:     return $ret;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Prepares a cached item.
Chris@0:    *
Chris@0:    * Checks that items are either permanent or did not expire, and returns data
Chris@0:    * as appropriate.
Chris@0:    *
Chris@0:    * @param object $cache
Chris@18:    *   An item loaded from self::get() or self::getMultiple().
Chris@0:    * @param bool $allow_invalid
Chris@0:    *   If FALSE, the method returns FALSE if the cache item is not valid.
Chris@0:    *
Chris@0:    * @return mixed
Chris@0:    *   The item with data as appropriate or FALSE if there is no
Chris@0:    *   valid item to load.
Chris@0:    */
Chris@0:   protected function prepareItem($cache, $allow_invalid) {
Chris@0:     if (!isset($cache->data)) {
Chris@0:       return FALSE;
Chris@0:     }
Chris@0: 
Chris@0:     // Check expire time.
Chris@0:     $cache->valid = $cache->expire == Cache::PERMANENT || $cache->expire >= REQUEST_TIME;
Chris@0: 
Chris@0:     // Check if invalidateTags() has been called with any of the item's tags.
Chris@0:     if (!$this->checksumProvider->isValid($cache->checksum, $cache->tags)) {
Chris@0:       $cache->valid = FALSE;
Chris@0:     }
Chris@0: 
Chris@0:     if (!$allow_invalid && !$cache->valid) {
Chris@0:       return FALSE;
Chris@0:     }
Chris@0: 
Chris@0:     return $cache;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function set($cid, $data, $expire = Cache::PERMANENT, array $tags = []) {
Chris@14:     assert(Inspector::assertAllStrings($tags), 'Cache Tags must be strings.');
Chris@14: 
Chris@0:     $item = (object) [
Chris@0:       'cid' => $cid,
Chris@0:       'data' => $data,
Chris@0:       'created' => round(microtime(TRUE), 3),
Chris@0:       'expire' => $expire,
Chris@0:       'tags' => array_unique($tags),
Chris@0:       'checksum' => $this->checksumProvider->getCurrentChecksum($tags),
Chris@0:     ];
Chris@0:     $this->writeItem($this->normalizeCid($cid), $item);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function delete($cid) {
Chris@0:     $this->storage()->delete($this->normalizeCid($cid));
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function deleteMultiple(array $cids) {
Chris@0:     foreach ($cids as $cid) {
Chris@0:       $this->delete($cid);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function deleteAll() {
Chris@0:     $this->storage()->deleteAll();
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function invalidate($cid) {
Chris@0:     $this->invalidatebyHash($this->normalizeCid($cid));
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Invalidate one cache item.
Chris@0:    *
Chris@0:    * @param string $cidhash
Chris@0:    *   The hashed version of the original cache ID after being normalized.
Chris@0:    */
Chris@0:   protected function invalidatebyHash($cidhash) {
Chris@0:     if ($item = $this->getByHash($cidhash)) {
Chris@0:       $item->expire = REQUEST_TIME - 1;
Chris@0:       $this->writeItem($cidhash, $item);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function invalidateMultiple(array $cids) {
Chris@0:     foreach ($cids as $cid) {
Chris@0:       $this->invalidate($cid);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function invalidateAll() {
Chris@0:     foreach ($this->storage()->listAll() as $cidhash) {
Chris@0:       $this->invalidatebyHash($cidhash);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function garbageCollection() {
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function removeBin() {
Chris@0:     $this->cache = [];
Chris@0:     $this->storage()->deleteAll();
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Writes a cache item to PhpStorage.
Chris@0:    *
Chris@0:    * @param string $cidhash
Chris@0:    *   The hashed version of the original cache ID after being normalized.
Chris@0:    * @param \stdClass $item
Chris@0:    *   The cache item to store.
Chris@0:    */
Chris@0:   protected function writeItem($cidhash, \stdClass $item) {
Chris@0:     $content = '<?php return unserialize(' . var_export(serialize($item), TRUE) . ');';
Chris@0:     $this->storage()->save($cidhash, $content);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Gets the PHP code storage object to use.
Chris@0:    *
Chris@0:    * @return \Drupal\Component\PhpStorage\PhpStorageInterface
Chris@0:    */
Chris@0:   protected function storage() {
Chris@0:     if (!isset($this->storage)) {
Chris@0:       $this->storage = PhpStorageFactory::get($this->bin);
Chris@0:     }
Chris@0:     return $this->storage;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Ensures a normalized cache ID.
Chris@0:    *
Chris@0:    * @param string $cid
Chris@0:    *   The passed in cache ID.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   A normalized cache ID.
Chris@0:    */
Chris@0:   protected function normalizeCid($cid) {
Chris@0:     return Crypt::hashBase64($cid);
Chris@0:   }
Chris@0: 
Chris@0: }