banker/src/Pool.php

269 lines
6.0 KiB
PHP

<?php
/**
* Banker
*
* A Caching library implementing psr/cache
*
* PHP version 5.6
*
* @package Banker
* @author Timothy J. Warren <tim@timshomepage.net>
* @copyright 2016 Timothy J. Warren
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @version 1.0.0
* @link https://git.timshomepage.net/timw4mail/banker
*/
namespace Aviat\Banker;
use Psr\Cache\CacheItemInterface;
use Psr\Cache\CacheItemPoolInterface;
use Aviat\Banker\Driver;
use Aviat\Banker\Driver\DriverInterface;
use Aviat\Banker\Exception\InvalidArgumentException;
use Aviat\Banker\Item;
/**
* The main cache manager
*/
class Pool implements CacheItemPoolInterface {
/**
* Driver class for handling the chosen caching backend
*
* @var DriverInterface
*/
protected $driver;
/**
* Cache Items to be saved
*
* @var array
*/
protected $deferred = [];
/**
* Set up the cache backend
*
* @param array $config
*/
public function __construct(array $config)
{
$this->driver = $this->loadDriver($config);
}
/**
* Returns a Cache Item representing the specified key.
*
* This method must always return a CacheItemInterface object, even in case of
* a cache miss. It MUST NOT return null.
*
* @param string $key
* The key for which to return the corresponding Cache Item.
*
* @throws InvalidArgumentException
* If the $key string is not a legal value a \Psr\Cache\InvalidArgumentException
* MUST be thrown.
*
* @return CacheItemInterface
* The corresponding Cache Item.
*/
public function getItem($key)
{
if ( ! is_string($key))
{
throw new InvalidArgumentException("Cache key must be a string.");
}
$item = new Item($this->driver, $key);
return $item;
}
/**
* Returns a traversable set of cache items.
*
* @param string[] $keys
* An indexed array of keys of items to retrieve.
*
* @throws InvalidArgumentException
* If any of the keys in $keys are not a legal value a \Psr\Cache\InvalidArgumentException
* MUST be thrown.
*
* @return array|\Traversable
* A traversable collection of Cache Items keyed by the cache keys of
* each item. A Cache item will be returned for each key, even if that
* key is not found. However, if no keys are specified then an empty
* traversable MUST be returned instead.
*/
public function getItems(array $keys = [])
{
// Get the set of items selected
$items = [];
foreach($keys as $key)
{
$items[$key] = $this->getItem($key);
}
return new ItemCollection($items);
}
/**
* Confirms if the cache contains specified cache item.
*
* Note: This method MAY avoid retrieving the cached value for performance reasons.
* This could result in a race condition with CacheItemInterface::get(). To avoid
* such situation use CacheItemInterface::isHit() instead.
*
* @param string $key
* The key for which to check existence.
*
* @throws InvalidArgumentException
* If the $key string is not a legal value a \Psr\Cache\InvalidArgumentException
* MUST be thrown.
*
* @return bool
* True if item exists in the cache, false otherwise.
*/
public function hasItem($key)
{
if ( ! is_string($key))
{
throw new InvalidArgumentException("Cache item must be a string");
}
return $this->driver->exists($key);
}
/**
* Deletes all items in the pool.
*
* @return bool
* True if the pool was successfully cleared. False if there was an error.
*/
public function clear()
{
return $this->driver->flush();
}
/**
* Removes the item from the pool.
*
* @param string $key
* The key to delete.
*
* @throws InvalidArgumentException
* If the $key string is not a legal value a \Psr\Cache\InvalidArgumentException
* MUST be thrown.
*
* @return bool
* True if the item was successfully removed. False if there was an error.
*/
public function deleteItem($key)
{
if ( ! is_string($key))
{
throw new InvalidArgumentException("Cache item must be a string");
}
if ( ! $this->hasItem($key))
{
return FALSE;
}
else
{
return $this->driver->delete($key);
}
}
/**
* Removes multiple items from the pool.
*
* @param string[] $keys
* An array of keys that should be removed from the pool.
* @throws InvalidArgumentException
* If any of the keys in $keys are not a legal value a \Psr\Cache\InvalidArgumentException
* MUST be thrown.
*
* @return bool
* True if the items were successfully removed. False if there was an error.
*/
public function deleteItems(array $keys)
{
foreach ($keys as $key)
{
if ( ! is_string($key))
{
throw new InvalidArgumentException("Cache item must be a string");
}
}
return $this->driver->deleteMultiple($keys);
}
/**
* Persists a cache item immediately.
*
* @param CacheItemInterface $item
* The cache item to save.
*
* @return bool
* True if the item was successfully persisted. False if there was an error.
*/
public function save(CacheItemInterface $item)
{
}
/**
* Sets a cache item to be persisted later.
*
* @param CacheItemInterface $item
* The cache item to save.
*
* @return bool
* False if the item could not be queued or if a commit was attempted and failed. True otherwise.
*/
public function saveDeferred(CacheItemInterface $item)
{
$this->deferred[] = $item;
}
/**
* Persists any deferred cache items.
*
* @return bool
* True if all not-yet-saved items were successfully saved or there were none. False otherwise.
*/
public function commit()
{
if (empty($this->deferred))
{
return TRUE;
}
$result = TRUE;
foreach($this->deferred as $item)
{
$result = $result && $this->save($item);
}
return $result;
}
/**
* Instantiate the appropriate cache backend based on the config
*
* @param array $driverConfig
* @return DriverInterface
*/
protected function loadDriver(array $driverConfig)
{
$driver = ucfirst(strtolower($driverConfig['driver']));
$class = "Driver\\${driver}Driver";
return new $class($driverConfig['connection']);
}
}