Ds\Cache\Storage\FileStorage

Complexity

Total Complexity

17

Size/Duplication

Total Lines	171
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	1

Test Coverage

Coverage

97.67%

Importance

Changes

0

7 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	14	4
A	set()	0	14	2
A	_createCacheItem()	0	13	2
A	has()	0	20	3
A	get()	0	13	2
A	delete()	0	4	1
A	clear()	0	13	3

<?php
/**
 * Src/Cache/Storage/FileStorage.php
 *
 * @package     Ds\Cache\Storage
 * @subpackage  Cache
 * @author      Dan Smith <dan--smith@hotmail.co.uk>
 * @version     v.1 (20/03/2017)
 * @copyright   Copyright (c) 2017, Dan Smith
 */
namespace Ds\Cache\Storage;

use \DateInterval;

/**
 * Class NullStorage
 *
 * @package Ds\Cache
 */
class FileStorage extends AbstractStorage
{
    /**
     * @var string
     */
    private $fs;

    /**
     * @var string
     */
    private $ext = 'cache';

    /**
     * File Storage constructor.
     *
     * @param string $file
     * @param DateInterval $ttl
     * @throws \Exception
     */
    public function __construct($file, DateInterval $ttl)
    {
        if (!is_string($file)){
            throw new \Exception('Directory must be a valid string');
        }

        $this->fs = $file;

        if(!@mkdir($this->fs, 0755) && !is_dir($this->fs)){
            throw new \Exception('unable to create directory');
        }

        parent::__construct($ttl);
    }

    /**
     * Persists data in the cache, uniquely referenced by a key with an optional expiration TTL time.
     *
     * @param \string   $key   The key of the item to store.
     * @param mixed    $value The value of the item to store, must be serializable.
     * @param null|\int $ttl   Optional. The TTL value of this item. If no value is sent and
     *                                     the driver supports TTL then the library may set a default value
     *                                     for it or let the driver take care of that.
     *
     * @return bool True on success and false on failure.
     */
    public function set($key, $value, $ttl = null)
    {
        $ttl = time() + $this->getTtlTimestamp($ttl);

        $cacheItem = $this->_createCacheItem($key, $value, $ttl);

        \file_put_contents($cacheItem['file'],$cacheItem['data']);

        if (!file_exists($cacheItem['file'])){
            return false;
        }

        return true;
    }

    /**
     * Create cache item.
     *
     * @param string $key
     * @param $value
     * @param int $ttl
     * @return array
     * @throws \Exception
     */
    private function _createCacheItem($key, $value, $ttl){

        if (!is_string($key)){
            throw new \Exception('$key must be a valid string');
        }

        $filename = implode('.',[$key,$this->ext]);

        return [
            'file' => $this->fs . DIRECTORY_SEPARATOR . $filename,
            'data' => json_encode([$ttl, $value])
        ];
    }

    /**
     * Determines whether an item is present in the cache.
     *
     * NOTE: It is recommended that has() is only to be used for cache warming type purposes
     * and not to be used within your live applications operations for get/set, as this method
     * is subject to a race condition where your has() will return true and immediately after,
     * another script can remove it making the state of your app out of date.
     *
     * @param string $key The cache item key.
     *
     * @return bool
     */
    public function has($key){

       $cacheFile = implode('.',[$key,$this->ext]);
       $cacheLocation = $this->fs . DIRECTORY_SEPARATOR . $cacheFile;

       if (!file_exists($cacheLocation)){
           return false;
       }

       $data = \file_get_contents($cacheLocation);
       $cacheData = json_decode($data, TRUE);

       //cache has expired
       if ($cacheData[0] < time() ){
           \unlink($cacheLocation);
           return false;
       }

       return true;
    }

    /**
     * Fetches a value from the cache.
     *
     * @param string $key     The unique key of this item in the cache.
     *
     * @return mixed The value of the item from the cache, or $default in case of cache miss.
     *
     */
    public function get($key){

        $cacheFile = implode('.',[$key,$this->ext]);
        $cacheLocation = $this->fs . DIRECTORY_SEPARATOR . $cacheFile;

        if ($this->has($key)){
            $data = \file_get_contents($cacheLocation);
            $cacheData = json_decode($data, TRUE);
            return $cacheData[1];
        }

        return null;
    }



    /**
     * Delete an item from the cache by its unique key.
     *
     * @param string $key The unique cache key of the item to delete.
     *
     * @return bool True if the item was successfully removed. False if there was an error.
     */
    public function delete($key)
    {
        return true;
    }

    /**
     * Wipes clean the entire cache's keys.
     *
     * @return bool True on success and false on failure.
     */
    public function clear(){
        if (is_dir( $this->fs )){
            array_map('unlink', glob("$this->fs/*.*"));
        }

        $data = glob("$this->fs/*.*");

        if (!empty($data)){
            return false;
        }

        return true;
    }
}