railpage/railpagecore

<?php

/**
 * Memcached controller for Railpage
 * @since Version 3.8.7
 * @package Railpage
 * @author Michael Greenhill
 */

namespace Railpage;

use StatsD;
use Memcached as PHPMemcached;
use Exception;
use DateTime;

/**
 * Memcached controller
 */

class Memcached {
    
    /**
     * Memcached host
     * @since Version 3.8.7
     * @var string $host
     */
    
    public $host;
    
    /**
     * Memcached port
     * @since Version 3.8.7
     * @var string $port
     */
    
    public $port;
    
    /**
     * Memcached connection
     * @since Version 3.8.7
     * @var object $cn
     */
    
    private $cn;
    
    /**
     * Constructor
     * @since Version 3.8.7
     * @return void
     */
    
    public function __construct() {
        if (!defined("DS")) {
            define("DS", DIRECTORY_SEPARATOR);
        }
        
        if (defined("RP_SITE_ROOT")) {
            $path = sprintf("%s%sconfig%sconfig.railpage.json", RP_SITE_ROOT, DS, DS);
        } else {
            $path = dirname(dirname(dirname(__DIR__))) . DS . "config" . DS . "config.railpage.json";
        }
        
        if (file_exists($path)) {
            $Config = json_decode(file_get_contents($path));
            
            $this->host = $Config->Memcached->Host;
            $this->port = $Config->Memcached->Port;
            
            $this->cn = new PHPMemcached;
            $this->cn->addServer($this->host, $this->port);
        }
    }
    
    /**
     * Check if Memcached is connected to a server
     * @return boolean
     */
    
    public function connected() {
        if ($this->cn instanceof PHPMemcached) {
            return true;
        } 
        
        return false;
    }

    /**
     * Cache an object in Memcache
     * @since Version 3.7.5
     * @param string $key
     * @param mixed $value
     * @param int $exp
     * @return boolean
     */
    
    function set($key = false, $value = "thisisanemptyvalue", $exp = 0) {
        if (!$key) {
            throw new Exception("Cannot set object in memcache - cache \$key cannot be empty"); 
            return false;
        }
        
        if ($value == "thisisanemptyvalue") {
            throw new Exception("Cannot set object in memcache - no \$value given for \$key"); 
            return false;
        }
        
        if (empty($value)) {
            trigger_error("Tried to set empty value for key " . $key . " in memcache. Are you sure it should be empty?", E_USER_WARNING); 
        }
        
        $timer = Debug::GetTimer(); 
        
        $rs = $this->cn->replace($key, $value, $exp); 
        $verb = "Update";
        
        if ($rs === false) {
            $rs = $this->cn->set($key, $value, $exp); 
            $verb = "Set";
        }
        
        Debug::LogEvent(($rs === false ? "Failed" : "Succeeded") . " " . $verb . " " . $key . " (" . strlen(serialize($value)) . "b object, expires " . $exp . ")", $timer); 
        
        StatsD::increment("rp.memcached.set");
    }
    
    /**
     * Put something into Memcached
     * @since Version 3.8.7
     * @return boolean
     */
    
    public function put($key, $value, $exp) {
        return $this->set($key, $value, $exp);
    }
    
    /**
     * Fetch an object from Memcache
     * @since Version 3.7.5
     * @param string $key
     * @return mixed
     */
    
    function get($key = false) {
        if (!$key) {
            throw new Exception("Cannot fetch object from memcache - \$key was not specified"); 
            return false;
        }
        
        $timer = Debug::GetTimer(); 
    
        $rs = $this->cn->get($key); 
        
        Debug::LogEvent(($rs === false ? "NOT FOUND" : "FOUND") . " " . $key, $timer); 
        
        StatsD::increment("rp.memcached.get");
        
        return $rs;
    }
    
    /**
     * Remove an object from Memcache
     * @since Version 3.7.5
     * @param string $key
     * @return mixed
     */
    
    function remove($key = false) {
        if (!$key) {
            throw new Exception("Cannot remove object from memcache - \$key was not specified"); 
            return false;
        }
        
        $timer = Debug::GetTimer(); 
        
        $rs = $this->cn->delete($key); 
        
        Debug::LogEvent(($rs === false ? "FAILED" : "SUCCEEDED") . " delete " . $key, $timer); 
        
        StatsD::increment("rp.memcached.delete");
        
        return $rs;
    }
    
    /**
     * Remove an object from Memcache
     * @since Version 3.7.5
     * @param string $key
     * @return mixed
     */
    
    function delete($key = false) {
        return $this->remove($key); 
    }
}