<?php
namespace Doctrine\Common\Cache;
use function array_combine;
use function array_key_exists;
use function array_map;
use function sprintf;
/**
* Base class for cache provider implementations.
*/
abstract class CacheProvider implements Cache, FlushableCache, ClearableCache, MultiOperationCache
{
public const DOCTRINE_NAMESPACE_CACHEKEY = 'DoctrineNamespaceCacheKey[%s]';
/**
* The namespace to prefix all cache ids with.
*
* @var string
*/
private $namespace = '';
/**
* The namespace version.
*
* @var int|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 [];
}
// note: the array_combine() is in place to keep an association between our $keys and the $namespacedKeys
$namespacedKeys = array_combine($keys, array_map([$this, 'getNamespacedId'], $keys));
$items = $this->doFetchMultiple($namespacedKeys);
$foundItems = [];
// no internal array function supports this sort of mapping: needs to be iterative
// this filters and combines keys in one pass
foreach ($namespacedKeys as $requestedKey => $namespacedKey) {
if (! isset($items[$namespacedKey]) && ! array_key_exists($namespacedKey, $items)) {
continue;
}
$foundItems[$requestedKey] = $items[$namespacedKey];
}
return $foundItems;
}
/**
* {@inheritdoc}
*/
public function saveMultiple(array $keysAndValues, $lifetime = 0)
{
$namespacedKeysAndValues = [];
foreach ($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 deleteMultiple(array $keys)
{
return $this->doDeleteMultiple(array_map([$this, 'getNamespacedId'], $keys));
}
/**
* {@inheritdoc}
*/
public function delete($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(string $id) : string
{
$namespaceVersion = $this->getNamespaceVersion();
return sprintf('%s[%s][%s]', $this->namespace, $id, $namespaceVersion);
}
/**
* Returns the namespace cache key.
*/
private function getNamespaceCacheKey() : string
{
return sprintf(self::DOCTRINE_NAMESPACE_CACHEKEY, $this->namespace);
}
/**
* Returns the namespace version.
*/
private function getNamespaceVersion() : int
{
if ($this->namespaceVersion !== null) {
return $this->namespaceVersion;
}
$namespaceCacheKey = $this->getNamespaceCacheKey();
$this->namespaceVersion = (int) $this->doFetch($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)
{
$returnValues = [];
foreach ($keys as $key) {
$item = $this->doFetch($key);
if ($item === false && ! $this->doContains($key)) {
continue;
}
$returnValues[$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)) {
continue;
}
$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);
/**
* Default implementation of doDeleteMultiple. Each driver that supports multi-delete should override it.
*
* @param array $keys Array of keys to delete from cache
*
* @return bool TRUE if the operation was successful, FALSE if it wasn't
*/
protected function doDeleteMultiple(array $keys)
{
$success = true;
foreach ($keys as $key) {
if ($this->doDelete($key)) {
continue;
}
$success = false;
}
return $success;
}
/**
* 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.
*
* @return array|null An associative array with server's statistics if available, NULL otherwise.
*/
abstract protected function doGetStats();
}