Fix #371 - fast APCu memory caching support

changelog.php

@@ -54,6 +54,7 @@ if (user_logged_in()) {
 <h1>Changelog</h1>
 <?php
 $cache = new Cache('engine/cache/changelog');
+$cache->useMemory(false);
 if ($updateCache === true) {
 	$changelogs = mysql_select_multi("SELECT `id`, `text`, `time`, `report_id`, `status` FROM `znote_changelog` ORDER BY `id` DESC;");
 

config.php

@@ -658,8 +658,15 @@
 		'name' => 'Forgotten' // Must be identical to config.lua (OT config file) server name.
 	);
 
-	// How often do you want highscores to update?
-	$config['cache_lifespan'] = 5; // 60 * 15; // 15 minutes.
+	// How often do you want highscores (cache) to update?
+	$config['cache'] = array(
+		// If you have two instances installed on same server, make each instance prefix unique
+		'prefix' => 'znote_',
+		// 60 * 15; // 15 minutes.
+		'lifespan' => 5,
+		// Store cache in memory/RAM? Requires PHP extension APCu
+		'memory' => true
+	);
 
 	// WARNING! Account names written here will have admin access to web page!
 	$config['page_admin_access'] = array(

engine/function/cache.php

@@ -5,6 +5,8 @@
 	protected $_file = false;
 	protected $_lifespan = 0;
 	protected $_content;
+	protected $_memory = false;
+	protected $_canMemory = false;
 
 	const EXT = '.cache.php';
 
@@ -15,8 +17,22 @@
 	 * @return void
 	**/
 	public function __construct($file) {
+		$cfg = config('cache');
+
+		$this->setExpiration($cfg['lifespan']);
+		if (function_exists('apcu_fetch')) {
+			$this->_canMemory = true;
+			$this->_memory = $cfg['memory'];
+		}
 		$this->_file = $file . self::EXT;
-			$this->setExpiration(config('cache_lifespan'));
+
+		if (!$this->_memory && $cfg['memory']) die("
+			<p><strong>Configuration error!</strong>
+			<br>Cannot save cache to memory, but it is configured to do so.
+			<br>You need to enable PHP extension APCu to enable memory cache.
+			<br>Install it or set \$config['cache']['memory'] to false!
+			<br><strong>Ubuntu install:</strong> sudo apt install php-apcu</p>
+		");
 	}
 
 
@@ -32,6 +48,23 @@
 	}
 
 
+	/**
+	 * Enable or disable memory RAM storage.
+	 *
+	 * @param  bool $bool
+	 * @access public
+	 * @return bool $status
+	**/
+	public function useMemory($bool) {
+		if ($bool and $this->_canMemory) {
+			$this->_memory = true;
+			return true;
+		}
+		$this->_memory = false;
+		return false;
+	}
+
+
 	/**
 	 * Set the content you'd like to cache.
 	 *
@@ -40,15 +73,7 @@
 	 * @return void
 	**/
 	public function setContent($content) {
-			switch (strtolower(gettype($content))) {
-				case 'array':
-					$this->_content = json_encode($content);
-					break;
-
-				default:
-					$this->_content = $content;
-					break;
-			}
+		$this->_content = (!$this->_memory && strtolower(gettype($content)) == 'array') ? json_encode($content) : $content;
 	}
 
 
@@ -59,10 +84,12 @@
 	 * @return boolean
 	**/
 	public function hasExpired() {
+		if ($this->_memory) {
+			return !apcu_exists($this->_file);
+		}
 		if (is_file($this->_file) && time() < filemtime($this->_file) + $this->_lifespan) {
 			return false;
 		}
-
 		return true;
 	}
 
@@ -74,6 +101,18 @@
 	**/
 	public function remainingTime() {
 		$remaining = 0;
+		if ($this->_memory) {
+			if (apcu_exists($this->_file)) {
+				$meta = apc_cache_info('user');
+				foreach ($meta['cache_list'] AS $item) {
+					if ($item['info'] == $this->_file) {
+						$remaining = ($item['creation_time'] + $item['ttl']) - time();
+						return ($remaining > 0) ? $remaining : 0;
+					}
+				}
+			}
+			return $remaining;
+		}
 		if (!$this->hasExpired()) {
 			$remaining = (filemtime($this->_file) + $this->_lifespan) - time();
 		}
@@ -88,6 +127,9 @@
 	 * @return void
 	**/
 	public function save() {
+		if ($this->_memory) {
+			return apcu_store($this->_file, $this->_content, $this->_lifespan);
+		}
 		$handle = fopen($this->_file, 'w');
 		fwrite($handle, $this->_content);
 		fclose($handle);
@@ -101,6 +143,9 @@
 	 * @return mixed
 	**/
 	public function load() {
+		if ($this->_memory) {
+			return apcu_fetch($this->_file);
+		}
 		if (!is_file($this->_file)) {
 			return false;
 		}

index.php

@@ -15,6 +15,7 @@ require_once 'engine/init.php'; include 'layout/overall/header.php';
 			// Changelog ticker //
 			// Load from cache
 			$changelogCache = new Cache('engine/cache/changelog');
+			$changelogCache->useMemory(false);
 			$changelogs = $changelogCache->load();
 
 			if (isset($changelogs) && !empty($changelogs) && $changelogs !== false) {

layout/sub/index.php

@@ -4,6 +4,7 @@ if ($config['UseChangelogTicker']) {
 	// Changelog ticker //
 	// Load from cache
 	$changelogCache = new Cache('engine/cache/changelog');
+	$changelogCache->useMemory(false);
 	$changelogs = $changelogCache->load();
 
 	if (isset($changelogs) && !empty($changelogs) && $changelogs !== false) {