KVDB php class for SAE

<?php
class kvdb
{
	public $kvdb; //SAE kvdb

	public function __construct()
	{
		$this->kvdb = new SaeKV();
		$this->kvdb->init();
	}

	public function get($key)
	{
		return $this->kvdb->get($key);
	}

	public function set($key, $value)
	{
		return $this->kvdb->set($key, $value);
	}

	public function replace($key, $value)
	{
		return $this->kvdb->replace($key, $value);
	}

	public function delete($key)
	{
		return $this->kvdb->delete($key);
	}

	public function mget($array)
	{
		return $this->kvdb->mget($array);
	}

	public function pkrget($prefix, $num=10, $offset='')
	{
		return $this->kvdb->pkrget($prefix, $num, $offset);
	}

	public function errmsg()
	{
		return $this->kvdb->errmsg();
	}


	/**
	 * kvdb cache
	 */
	public function cache ($action, $key, $value='', $timeout=300)
	{
		$key = 'cache_' . $key;
		switch ($action)
		{
			case 'get':
				return $this->cache_get($key);
				break;

			case 'set':
				return $this->cache_set($key, $value, $timeout);
				break;

			case 'delete':
				return $this->cache_delete($key);
				break;
			
			default:
				return false;
				break;
		}
	}

	public function cache_get ($key)
	{
		$data = $this->get($key);
		if ($data)
		{
			$array = unserialize($data);
			if (isset($array['timeout']) && ($array['timeout'] > time()) )
				$data = $array['data'];
			else
				$data = ''; // 应用场景中此处缓存马上会更新，无法删除操作。
		}
		return $data;
	}

	public function cache_set ($key, $value, $timeout)
	{
		$array = array(
			'data' => $value,
			'timeout' => time() + $timeout
		);
		return $this->set($key, serialize($array));
	}

	public function cache_delete ($key)
	{
		return $this->delete($key);
	}
}