--- /dev/null
+<?php
+/*
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the MIT license. For more information, see
+ * <http://www.doctrine-project.org>.
+ */
+
+namespace Doctrine\Common\Cache;
+
+/**
+ * Base class for cache provider implementations.
+ *
+ * @since 2.2
+ * @author Benjamin Eberlei <kontakt@beberlei.de>
+ * @author Guilherme Blanco <guilhermeblanco@hotmail.com>
+ * @author Jonathan Wage <jonwage@gmail.com>
+ * @author Roman Borschel <roman@code-factory.org>
+ * @author Fabio B. Silva <fabio.bat.silva@gmail.com>
+ */
+abstract class CacheProvider implements Cache, FlushableCache, ClearableCache, MultiGetCache, MultiPutCache
+{
+ const DOCTRINE_NAMESPACE_CACHEKEY = 'DoctrineNamespaceCacheKey[%s]';
+
+ /**
+ * The namespace to prefix all cache ids with.
+ *
+ * @var string
+ */
+ private $namespace = '';
+
+ /**
+ * The namespace version.
+ *
+ * @var integer|null
+ */
+ private $namespaceVersion;
+
+ /**
+ * Sets the namespace to prefix all cache ids with.
+ *
+ * @param string $namespace
+ *
+ * @return void
+ */
+ public function setNamespace($namespace)
+ {
+ $this->namespace = (string) $namespace;
+ $this->namespaceVersion = null;
+ }
+
+ /**
+ * Retrieves the namespace that prefixes all cache ids.
+ *
+ * @return string
+ */
+ public function getNamespace()
+ {
+ return $this->namespace;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function fetch($id)
+ {
+ return $this->doFetch($this->getNamespacedId($id));
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function fetchMultiple(array $keys)
+ {
+ if (empty($keys)) {
+ return array();
+ }
+
+ // note: the array_combine() is in place to keep an association between our $keys and the $namespacedKeys
+ $namespacedKeys = array_combine($keys, array_map(array($this, 'getNamespacedId'), $keys));
+ $items = $this->doFetchMultiple($namespacedKeys);
+ $foundItems = array();
+
+ // no internal array function supports this sort of mapping: needs to be iterative
+ // this filters and combines keys in one pass
+ foreach ($namespacedKeys as $requestedKey => $namespacedKey) {
+ if (isset($items[$namespacedKey]) || array_key_exists($namespacedKey, $items)) {
+ $foundItems[$requestedKey] = $items[$namespacedKey];
+ }
+ }
+
+ return $foundItems;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function saveMultiple(array $keysAndValues, $lifetime = 0)
+ {
+ $namespacedKeysAndValues = array();
+ foreach ($keysAndValues as $key => $value) {
+ $namespacedKeysAndValues[$this->getNamespacedId($key)] = $value;
+ }
+
+ return $this->doSaveMultiple($namespacedKeysAndValues, $lifetime);
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function contains($id)
+ {
+ return $this->doContains($this->getNamespacedId($id));
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function save($id, $data, $lifeTime = 0)
+ {
+ return $this->doSave($this->getNamespacedId($id), $data, $lifeTime);
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function delete($id)
+ {
+ return $this->doDelete($this->getNamespacedId($id));
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getStats()
+ {
+ return $this->doGetStats();
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ public function flushAll()
+ {
+ return $this->doFlush();
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ public function deleteAll()
+ {
+ $namespaceCacheKey = $this->getNamespaceCacheKey();
+ $namespaceVersion = $this->getNamespaceVersion() + 1;
+
+ if ($this->doSave($namespaceCacheKey, $namespaceVersion)) {
+ $this->namespaceVersion = $namespaceVersion;
+
+ return true;
+ }
+
+ return false;
+ }
+
+ /**
+ * Prefixes the passed id with the configured namespace value.
+ *
+ * @param string $id The id to namespace.
+ *
+ * @return string The namespaced id.
+ */
+ private function getNamespacedId($id)
+ {
+ $namespaceVersion = $this->getNamespaceVersion();
+
+ return sprintf('%s[%s][%s]', $this->namespace, $id, $namespaceVersion);
+ }
+
+ /**
+ * Returns the namespace cache key.
+ *
+ * @return string
+ */
+ private function getNamespaceCacheKey()
+ {
+ return sprintf(self::DOCTRINE_NAMESPACE_CACHEKEY, $this->namespace);
+ }
+
+ /**
+ * Returns the namespace version.
+ *
+ * @return integer
+ */
+ private function getNamespaceVersion()
+ {
+ if (null !== $this->namespaceVersion) {
+ return $this->namespaceVersion;
+ }
+
+ $namespaceCacheKey = $this->getNamespaceCacheKey();
+ $this->namespaceVersion = $this->doFetch($namespaceCacheKey) ?: 1;
+
+ return $this->namespaceVersion;
+ }
+
+ /**
+ * Default implementation of doFetchMultiple. Each driver that supports multi-get should owerwrite it.
+ *
+ * @param array $keys Array of keys to retrieve from cache
+ * @return array Array of values retrieved for the given keys.
+ */
+ protected function doFetchMultiple(array $keys)
+ {
+ $returnValues = array();
+
+ foreach ($keys as $key) {
+ if (false !== ($item = $this->doFetch($key)) || $this->doContains($key)) {
+ $returnValues[$key] = $item;
+ }
+ }
+
+ return $returnValues;
+ }
+
+ /**
+ * Fetches an entry from the cache.
+ *
+ * @param string $id The id of the cache entry to fetch.
+ *
+ * @return mixed|false The cached data or FALSE, if no cache entry exists for the given id.
+ */
+ abstract protected function doFetch($id);
+
+ /**
+ * Tests if an entry exists in the cache.
+ *
+ * @param string $id The cache id of the entry to check for.
+ *
+ * @return bool TRUE if a cache entry exists for the given cache id, FALSE otherwise.
+ */
+ abstract protected function doContains($id);
+
+ /**
+ * Default implementation of doSaveMultiple. Each driver that supports multi-put should override it.
+ *
+ * @param array $keysAndValues Array of keys and values to save in cache
+ * @param int $lifetime The lifetime. If != 0, sets a specific lifetime for these
+ * cache entries (0 => infinite lifeTime).
+ *
+ * @return bool TRUE if the operation was successful, FALSE if it wasn't.
+ */
+ protected function doSaveMultiple(array $keysAndValues, $lifetime = 0)
+ {
+ $success = true;
+
+ foreach ($keysAndValues as $key => $value) {
+ if (!$this->doSave($key, $value, $lifetime)) {
+ $success = false;
+ }
+ }
+
+ return $success;
+ }
+
+ /**
+ * Puts data into the cache.
+ *
+ * @param string $id The cache id.
+ * @param string $data The cache entry/data.
+ * @param int $lifeTime The lifetime. If != 0, sets a specific lifetime for this
+ * cache entry (0 => infinite lifeTime).
+ *
+ * @return bool TRUE if the entry was successfully stored in the cache, FALSE otherwise.
+ */
+ abstract protected function doSave($id, $data, $lifeTime = 0);
+
+ /**
+ * Deletes a cache entry.
+ *
+ * @param string $id The cache id.
+ *
+ * @return bool TRUE if the cache entry was successfully deleted, FALSE otherwise.
+ */
+ abstract protected function doDelete($id);
+
+ /**
+ * Flushes all cache entries.
+ *
+ * @return bool TRUE if the cache entries were successfully flushed, FALSE otherwise.
+ */
+ abstract protected function doFlush();
+
+ /**
+ * Retrieves cached information from the data store.
+ *
+ * @since 2.2
+ *
+ * @return array|null An associative array with server's statistics if available, NULL otherwise.
+ */
+ abstract protected function doGetStats();
+}