Added a simple cache implementation

HandBrakeCluster/Cache.class.php

@@ -0,0 +1,60 @@
+<?php
+
+class HandBrakeCluster_Cache {
+    
+    protected $config;
+    protected $cache_dir;
+    
+    public function __construct(HandBrakeCluster_Config $config) {
+        $this->config = $config;
+        $this->cache_dir = $config->get('cache.base_dir');
+        
+        if (is_dir($cache_dir)) {
+            if ( ! is_writeable($cache_dir)) {
+                throw new HandBrakeCluster_Exception_InvalidCacheDir();
+            }
+        } else {
+            if ( ! HandBrakeCluster_Main::mkdir_recursive($this->cache_dir)) {
+                throw new HandBrakeCluster_Exception_InvalidCacheDir();
+            }
+        }
+    }
+    
+    protected function cacheFilename($source_filename) {
+        return $this->cache_dir . sha1($source_filename);
+    }
+    
+    public function exists($source_filename, $ttl = 3600) {
+        $cache_filename = $this->cacheFilename($source_filename);
+        
+        // Check to see if the file is cached
+        if (!file_exists($cache_filename)) {
+            return false;
+        }
+        
+        // Check to see if the cache has expired
+        if (filemtime($cache_filename) + $ttl < time()) {
+            return false;
+        }
+        
+        return true;
+    }
+    
+    public function store($source_filename, $content) {
+        $cache_filename = $this->cacheFilename($source_filename);
+        return file_put_contents($cache_filename, $content);
+    }
+    
+    public function fetch($source_filename, $ttl = 3600) {
+        $cache_filename = $this->cacheFilename($source_filename);
+        
+        if (!$this->exists($source_filename)) {
+            throw new HandBrakeCluster_Exception_CacheObjectNotFound($source_filename);
+        }
+        
+        return file_get_contents($cache_filename);
+    }
+    
+};
+
+?>

HandBrakeCluster/Main.class.php

@@ -11,6 +11,7 @@ class HandBrakeCluster_Main {
     private $database;
     private $log;
     private $request;
+    private $cache;
 
     private function __construct() {
         $request_string = isset($_GET['l']) ? $_GET['l'] : '';
@@ -21,6 +22,7 @@ class HandBrakeCluster_Main {
 
         $this->log      = new HandBrakeCluster_Log($this->database, $this->config);
         $this->request  = new HandBrakeCluster_RequestParser($request_string);
+        $this->cache    = new HandBrakeCluster_Cache($this->config);
         
         $this->smarty = new Smarty();
         $this->smarty->template_dir = './templates';
@@ -61,6 +63,10 @@ class HandBrakeCluster_Main {
         return $this->request;
     }
     
+    public function cache() {
+        return $this->cache;
+    }
+
     public static function initialise() {
         spl_autoload_register(array('HandBrakeCluster_Main','autoload'));
     }
@@ -93,6 +99,21 @@ class HandBrakeCluster_Main {
             require_once $filename;
         }
     }
+    
+    public static function mkdir_recursive($directory, $permissions=0777) {
+        $parts = explode('/', $directory);
+        $path = '';
+        for ($i=1,$l=count($parts); $i<=$l; $i++) {
+            $iPath = $parts;
+            $path = join('/', array_slice($iPath, 0, $i));
+            if (empty($path)) continue;
+            if (!file_exists($path)) {
+                if (!mkdir($path)) return false;
+                if (!chmod($path, $permissions)) return false;
+            }
+        }
+        return true;
+    }
 }
 
 HandBrakeCluster_Main::initialise();