Improved cache system

Author: marcocesarato

README.md

@@ -1,7 +1,7 @@
 # PHP Database Web API
 ![](cover.png)
 
-**Version:** 0.6.128 beta
+**Version:** 0.6.129 beta
 
 **Github:** https://github.com/marcocesarato/Database-Web-API
 
@@ -62,12 +62,13 @@ define("__API_NAME__", "Database Web API"); // API Name
 
 | Settings         | Description                                                                        | Default   |
 |------------------|------------------------------------------------------------------------------------|-----------|
-| default          | Default dataset                                                              | false     |
-| api              | Accessible through API                                                          | true      |
+| default          | Default dataset                                                                    | false     |
+| api              | Accessible through API                                                             | true      |
 | name             | Database Name                                                                      |           |
 | username         | Database Username                                                                  | root      |
 | password         | Database Password                                                                  | root      |
 | server           | Database Server Address                                                            | localhost |
+| ttl              | Cache time to live (set 1 for disable)                                             | 3600      |
 | port             | Database Port                                                                      | 3306      |
 | type             | Database Type (ex. `mysql`, `psql` ecc..)                                          | mysql     |
 | table_list       | Database Tables Whitelist (Allow only the tables in this list, if empty allow all) | null      |
@@ -85,6 +86,7 @@ define("__API_DATASETS__", serialize(array(
 		'name' => 'database_name', // Database name
 		'username' => 'user', // root is default
 		'password' => 'passwd', // root is default
+		'ttl' => 1, // Cache time to live. Disable cache (1 second only)
 		'server' => 'localhost',  // localhost default
 		'port' => 5432, // 3306 is default
 		'type' => 'pgsql', // mysql is default
@@ -133,6 +135,7 @@ array(
 	'username' => 'website',
 	'password' => 's3cr3tpa55w0rd',
 	'server' => 'localhost',
+	'ttl' => 1,
 	'port' => 3306,
 	'type' => 'mysql',
 	'table_docs' => array(),

config.php

@@ -43,6 +43,7 @@
 		'password'         => 'root', // root is default
 		'server'           => 'localhost',  // localhost default
 		'port'             => 3306, // 3306 is default
+		'ttl'              => 1, // Cache time to live. Disable cache (1 second only)
 		'type'             => 'mysql', // mysql is default
 		'table_docs'       => $docs['dataset'],
 		'table_list'       => array(), // Tables's whitelist (Allow only the tables in this list, if empty allow all)

includes/classes/API.php

@@ -400,7 +400,7 @@ private function documentation($query, $db = null) {
 
 		$final_result = array();
 
-		$key = md5(serialize($query) . $this->getDatabase($db)->name . '_docs');
+		$key = md5(json_encode($query) . $this->getDatabase($db)->name . '_docs');
 
 		if($cache = $this->getCache($key)) {
 			return $cache;
@@ -503,7 +503,7 @@ private function documentation($query, $db = null) {
 	 */
 	private function get($query, $db = null) {
 
-		$key = md5(serialize($query) . $this->getDatabase($db)->name);
+		$key = md5(json_encode($query) . $this->getDatabase($db)->name);
 
 		if($cache = $this->getCache($key)) {
 			return $cache;
@@ -1749,11 +1749,21 @@ private function sanitizeResults($results) {
 	 */
 	private function getCache($key) {
 
-		if(!extension_loaded('apc') || (ini_get('apc.enabled') != 1)) {
-			if(!empty($this->cache[$key])) {
-				return $this->cache[$key];
+		$tmpdir = sys_get_temp_dir();
+		if(!empty($this->cache[$key])) {
+			return $this->cache[$key];
+		} else if((ini_get('opcache.enable') == 0 || ini_get('apc.enabled') == 0) && is_writable($tmpdir)) {
+			$file = $tmpdir . DIRECTORY_SEPARATOR . $key;
+			$ttl = (!empty($this->db->ttl)) ? $this->db->ttl : $this->ttl;
+			if(file_exists($file)) {
+				if((time() - @filectime($file) < $ttl)) {
+					@unlink($file);
+				} else {
+					@include($file);
+				}
 			}
-		} else {
+			return isset($value) ? $value : false;
+		} else if(extension_loaded('apc') || (ini_get('apc.enabled') == 1)) {
 			return apc_fetch($key);
 		}
 
@@ -1769,18 +1779,27 @@ private function getCache($key) {
 	 */
 	private function setCache($key, $value, $ttl = null) {
 
-		if($ttl == null) {
+		$this->cache[$key] = $value;
+
+		$tmpdir = sys_get_temp_dir();
+		if((ini_get('opcache.enable') == 0 || ini_get('apc.enabled') == 0) && is_writable($tmpdir)) {
+			$value = var_export($value, true);
+			// HHVM fails at __set_state, so just use object cast for now
+			$value = str_replace('stdClass::__set_state', '(object)', $value);
+			// Write to temp file first to ensure atomicity
+			$tmp = $tmpdir . DIRECTORY_SEPARATOR . $key . "." . uniqid('', true) . '.tmp';
+			file_put_contents($tmp, '<?php $val = ' . $value . ';', LOCK_EX);
+			rename($tmp, $tmpdir . DIRECTORY_SEPARATOR . $key);
+
+		} else if($ttl == null) {
 			$ttl = (!empty($this->db->ttl)) ? $this->db->ttl : $this->ttl;
 		}
-
 		$key = 'api_' . $key;
 
 		if(extension_loaded('apc') && (ini_get('apc.enabled') == 1)) {
 			return apc_store($key, $value, $ttl);
 		}
 
-		$this->cache[$key] = $value;
-
 		return true;
 	}
 }