feature symfony#20694 [Cache] Implement PSR-16 SimpleCache v1.0 (nicolas-grekas)

This PR was squashed before being merged into the 3.3-dev branch (closes symfony#20694).

Discussion
----------

[Cache] Implement PSR-16 SimpleCache v1.0

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | not yet
| Fixed tickets | -
| License       | MIT
| Doc PR        | symfony/symfony-docs#7409

Second iteration on the topic after symfony#20636 raised some issues.

Please don't squash while merging.

Commits
-------

6219dd6 [Cache] Create PSR-16 variants of all PSR-6 adapters
99ae9d6 [Cache] Move adapter implementations to traits
848a33e [Cache] Implement PSR-16 SimpleCache v1.0

Author: fabpot

composer.json

@@ -21,6 +21,7 @@
         "twig/twig": "~1.28|~2.0",
         "psr/cache": "~1.0",
         "psr/log": "~1.0",
+        "psr/simple-cache": "^1.0",
         "symfony/polyfill-intl-icu": "~1.0",
         "symfony/polyfill-mbstring": "~1.0",
         "symfony/polyfill-php56": "~1.0",
@@ -79,7 +80,7 @@
         "symfony/yaml": "self.version"
     },
     "require-dev": {
-        "cache/integration-tests": "dev-master",
+        "cache/integration-tests": "^0.15.0",
         "doctrine/cache": "~1.6",
         "doctrine/data-fixtures": "1.0.*",
         "doctrine/dbal": "~2.4",
@@ -99,7 +100,8 @@
         "phpdocumentor/type-resolver": "<0.2.0"
     },
     "provide": {
-        "psr/cache-implementation": "1.0"
+        "psr/cache-implementation": "1.0",
+        "psr/simple-cache-implementation": "1.0"
     },
     "autoload": {
         "psr-4": {

phpunit.xml.dist

@@ -62,6 +62,8 @@
                         <array>
                             <element><string>Cache\IntegrationTests</string></element>
                             <element><string>Doctrine\Common\Cache</string></element>
+                            <element><string>Symfony\Component\Cache</string></element>
+                            <element><string>Symfony\Component\Cache\Traits</string></element>
                             <element><string>Symfony\Component\Console</string></element>
                             <element><string>Symfony\Component\HttpFoundation</string></element>
                         </array>

src/Symfony/Component/Cache/Adapter/AbstractAdapter.php

@@ -13,31 +13,24 @@
 
 use Psr\Cache\CacheItemInterface;
 use Psr\Log\LoggerAwareInterface;
-use Psr\Log\LoggerAwareTrait;
 use Psr\Log\LoggerInterface;
 use Symfony\Component\Cache\CacheItem;
 use Symfony\Component\Cache\Exception\InvalidArgumentException;
+use Symfony\Component\Cache\Traits\AbstractTrait;
 
 /**
  * @author Nicolas Grekas <p@tchwork.com>
  */
 abstract class AbstractAdapter implements AdapterInterface, LoggerAwareInterface
 {
-    use LoggerAwareTrait;
+    use AbstractTrait;
 
     private static $apcuSupported;
     private static $phpFilesSupported;
 
-    private $namespace;
-    private $deferred = array();
     private $createCacheItem;
     private $mergeByLifetime;
 
-    /**
-     * @var int|null The maximum length to enforce for identifiers or null when no limit applies
-     */
-    protected $maxIdLength;
-
     protected function __construct($namespace = '', $defaultLifetime = 0)
     {
         $this->namespace = '' === $namespace ? '' : $this->getId($namespace).':';
@@ -130,52 +123,6 @@ public static function createConnection($dsn, array $options = array())
         throw new InvalidArgumentException(sprintf('Unsupported DSN: %s.', $dsn));
     }
 
-    /**
-     * Fetches several cache items.
-     *
-     * @param array $ids The cache identifiers to fetch
-     *
-     * @return array|\Traversable The corresponding values found in the cache
-     */
-    abstract protected function doFetch(array $ids);
-
-    /**
-     * Confirms if the cache contains specified cache item.
-     *
-     * @param string $id The identifier for which to check existence
-     *
-     * @return bool True if item exists in the cache, false otherwise
-     */
-    abstract protected function doHave($id);
-
-    /**
-     * Deletes all items in the pool.
-     *
-     * @param string The prefix used for all identifiers managed by this pool
-     *
-     * @return bool True if the pool was successfully cleared, false otherwise
-     */
-    abstract protected function doClear($namespace);
-
-    /**
-     * Removes multiple items from the pool.
-     *
-     * @param array $ids An array of 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);
-
-    /**
-     * 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
-     *
-     * @return array|bool The identifiers that failed to be cached or a boolean stating if caching succeeded or not
-     */
-    abstract protected function doSave(array $values, $lifetime);
-
     /**
      * {@inheritdoc}
      */
@@ -225,87 +172,6 @@ public function getItems(array $keys = array())
         return $this->generateItems($items, $ids);
     }
 
-    /**
-     * {@inheritdoc}
-     */
-    public function hasItem($key)
-    {
-        $id = $this->getId($key);
-
-        if (isset($this->deferred[$key])) {
-            $this->commit();
-        }
-
-        try {
-            return $this->doHave($id);
-        } catch (\Exception $e) {
-            CacheItem::log($this->logger, 'Failed to check if key "{key}" is cached', array('key' => $key, 'exception' => $e));
-
-            return false;
-        }
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function clear()
-    {
-        $this->deferred = array();
-
-        try {
-            return $this->doClear($this->namespace);
-        } catch (\Exception $e) {
-            CacheItem::log($this->logger, 'Failed to clear the cache', array('exception' => $e));
-
-            return false;
-        }
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function deleteItem($key)
-    {
-        return $this->deleteItems(array($key));
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function deleteItems(array $keys)
-    {
-        $ids = array();
-
-        foreach ($keys as $key) {
-            $ids[$key] = $this->getId($key);
-            unset($this->deferred[$key]);
-        }
-
-        try {
-            if ($this->doDelete($ids)) {
-                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(array($id))) {
-                    continue;
-                }
-            } catch (\Exception $e) {
-            }
-            CacheItem::log($this->logger, 'Failed to delete key "{key}"', array('key' => $key, 'exception' => $e));
-            $ok = false;
-        }
-
-        return $ok;
-    }
-
     /**
      * {@inheritdoc}
      */
@@ -394,47 +260,6 @@ public function __destruct()
         }
     }
 
-    /**
-     * Like the native unserialize() function but throws an exception if anything goes wrong.
-     *
-     * @param string $value
-     *
-     * @return mixed
-     *
-     * @throws \Exception
-     */
-    protected static function unserialize($value)
-    {
-        if ('b:0;' === $value) {
-            return false;
-        }
-        $unserializeCallbackHandler = ini_set('unserialize_callback_func', __CLASS__.'::handleUnserializeCallback');
-        try {
-            if (false !== $value = unserialize($value)) {
-                return $value;
-            }
-            throw new \DomainException('Failed to unserialize cached value');
-        } catch (\Error $e) {
-            throw new \ErrorException($e->getMessage(), $e->getCode(), E_ERROR, $e->getFile(), $e->getLine());
-        } finally {
-            ini_set('unserialize_callback_func', $unserializeCallbackHandler);
-        }
-    }
-
-    private function getId($key)
-    {
-        CacheItem::validateKey($key);
-
-        if (null === $this->maxIdLength) {
-            return $this->namespace.$key;
-        }
-        if (strlen($id = $this->namespace.$key) > $this->maxIdLength) {
-            $id = $this->namespace.substr_replace(base64_encode(hash('sha256', $key, true)), ':', -22);
-        }
-
-        return $id;
-    }
-
     private function generateItems($items, &$keys)
     {
         $f = $this->createCacheItem;
@@ -453,12 +278,4 @@ private function generateItems($items, &$keys)
             yield $key => $f($key, null, false);
         }
     }
-
-    /**
-     * @internal
-     */
-    public static function handleUnserializeCallback($class)
-    {
-        throw new \DomainException('Class not found: '.$class);
-    }
 }

src/Symfony/Component/Cache/Adapter/ApcuAdapter.php

@@ -11,97 +11,14 @@
 
 namespace Symfony\Component\Cache\Adapter;
 
-use Symfony\Component\Cache\CacheItem;
-use Symfony\Component\Cache\Exception\CacheException;
+use Symfony\Component\Cache\Traits\ApcuTrait;
 
-/**
- * @author Nicolas Grekas <p@tchwork.com>
- */
 class ApcuAdapter extends AbstractAdapter
 {
-    public static function isSupported()
-    {
-        return function_exists('apcu_fetch') && ini_get('apc.enabled') && !('cli' === PHP_SAPI && !ini_get('apc.enable_cli'));
-    }
+    use ApcuTrait;
 
     public function __construct($namespace = '', $defaultLifetime = 0, $version = null)
     {
-        if (!static::isSupported()) {
-            throw new CacheException('APCu is not enabled');
-        }
-        if ('cli' === PHP_SAPI) {
-            ini_set('apc.use_request_time', 0);
-        }
-        parent::__construct($namespace, $defaultLifetime);
-
-        if (null !== $version) {
-            CacheItem::validateKey($version);
-
-            if (!apcu_exists($version.'@'.$namespace)) {
-                $this->clear($namespace);
-                apcu_add($version.'@'.$namespace, null);
-            }
-        }
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function doFetch(array $ids)
-    {
-        try {
-            return apcu_fetch($ids);
-        } catch (\Error $e) {
-            throw new \ErrorException($e->getMessage(), $e->getCode(), E_ERROR, $e->getFile(), $e->getLine());
-        }
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function doHave($id)
-    {
-        return apcu_exists($id);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function doClear($namespace)
-    {
-        return isset($namespace[0]) && class_exists('APCuIterator', false)
-            ? apcu_delete(new \APCuIterator(sprintf('/^%s/', preg_quote($namespace, '/')), APC_ITER_KEY))
-            : apcu_clear_cache();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function doDelete(array $ids)
-    {
-        foreach ($ids as $id) {
-            apcu_delete($id);
-        }
-
-        return true;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function doSave(array $values, $lifetime)
-    {
-        try {
-            return array_keys(apcu_store($values, null, $lifetime));
-        } catch (\Error $e) {
-        } catch (\Exception $e) {
-        }
-
-        if (1 === count($values)) {
-            // Workaround https://github.com/krakjoe/apcu/issues/170
-            apcu_delete(key($values));
-        }
-
-        throw $e;
+        $this->init($namespace, $defaultLifetime, $version);
     }
 }