DesignPatternsPHP/Behavioral/ChainOfResponsibilities/Responsible/SlowStorage.php

<?php

namespace DesignPatterns\Behavioral\ChainOfResponsibilities\Responsible;

use DesignPatterns\Behavioral\ChainOfResponsibilities\Handler;
use DesignPatterns\Behavioral\ChainOfResponsibilities\Request;

/**
 * This is mostly the same code as FastStorage but in fact, it may greatly differs.
 *
 * One important fact about CoR: each item in the chain MUST NOT assume its position
 * in the chain. A CoR is not responsible if the request is not handled UNLESS
 * you make an "ExceptionHandler" which throws exception if the request goes there.
 *
 * To be really extendable, each handler doesn't know if there is something after it.
 */
class SlowStorage extends Handler
{
    /**
     * @var array
     */
    protected $data = array();

    /**
     * @param array $data
     */
    public function __construct($data = array())
    {
        $this->data = $data;
    }

    protected function processing(Request $req)
    {
        if ('get' === $req->verb) {
            if (array_key_exists($req->key, $this->data)) {
                $req->response = $this->data[$req->key];

                return true;
            }
        }

        return false;
    }
}