FileStore.php

<?php
/**
 * Saves cached values in the file.
 *
 * @package SugiPHP.Cache
 * @author  Plamen Popov <tzappa@gmail.com>
 * @license http://opensource.org/licenses/mit-license.php (MIT License)
 */

namespace SugiPHP\Cache;

class FileStore implements StoreInterface
{
    /**
     * Path to directory where cache files will be saved.
     */
    protected $path;

    /**
     * Creates a File store
     *
     * @param string
     */
    public function __construct($path)
    {
        $this->path = rtrim($path, DIRECTORY_SEPARATOR) . DIRECTORY_SEPARATOR;
    }

    /**
     * {@inheritdoc}
     */
    public function add($key, $value, $ttl = 0)
    {
        if ($this->has($key)) {
            return false;
        }

        return $this->set($key, $value, $ttl);
    }

    /**
     * {@inheritdoc}
     */
    public function set($key, $value, $ttl = 0)
    {
        $file = $this->filename($key);
        $expire = ($ttl) ? time() + $ttl : "9999999999";
        // serializing is done mainly to distinguish type of the $value - string, number, etc.
        $contents = $expire.serialize($value);

        return (boolean) (@file_put_contents($file, $contents, LOCK_EX));
    }

    /**
     * {@inheritdoc}
     */
    public function get($key)
    {
        $file = $this->filename($key);
        if (!is_file($file)) {
            return null;
        }

        $contents = file_get_contents($file);

        // check TTL
        $expire = substr($contents, 0, 10);
        if ($expire < time()) {
            // if cache is expired delete cache file
            $this->delete($key);

            return null;
        }

        return unserialize(substr($contents, 10));
    }

    /**
     * {@inheritdoc}
     */
    public function has($key)
    {
        return (is_null($this->get($key))) ? false : true;
    }

    /**
     * {@inheritdoc}
     */
    public function delete($key)
    {
        @unlink($this->filename($key));
    }

    /**
     * {@inheritdoc}
     */
    public function flush()
    {
        $files = glob($this->path."*.cache");
        if ($files) {
            foreach ($files as $file) {
                @unlink($file);
            }
        }
    }

    /**
     * Generates a filename based on the $key parameter
     *
     * @param string $key
     *
     * @return string
     */
    protected function filename($key)
    {
        return $this->path.md5($key).".cache";
    }
}