set caching headers for media

controllers/MediaController.inc

@@ -45,6 +45,24 @@
 		
 		
 		
+		/**
+		 * Prefilter.
+		 * 
+		 * @param	Request		$request	Current request
+		 * @param	Response	$response	Current response
+		 */
+		public function preFilter(\nre\core\Request $request, \nre\core\Response $response)
+		{
+			parent::preFilter($request, $response);
+			
+			// Set headers for caching control
+			$response->addHeader("Pragma: public");
+			$response->addHeader("Cache-control: public, max-age=".(60*60*24));
+			$response->addHeader("Expires: ".gmdate('r', time()+(60*60*24)));
+			$response->addHeader("Date: ".gmdate(\DateTime::RFC822));
+		}
+		
+		
 		/**
 		 * Action: index.
 		 * 
@@ -71,11 +89,55 @@
 				throw new \nre\exceptions\IdNotFoundException($mediaUrl);
 			}
 			
+			// Cache
+			if($this->setCacheHeaders($media['filename'])) {
+				return;
+			}
+			
 			
 			// Pass data to view
 			$this->set('media', $media);
 		}
 		
+		
+		
+		
+		/**
+		 * Determine file information and set the HTTP-header for
+		 * caching accordingly.
+		 * 
+		 * @param	string	$fileName	Filename
+		 * @return	boolean			HTTP-status 304 was set (in cache)
+		 */
+		private function setCacheHeaders($fileName)
+		{
+			// Determine last change of file
+			$fileLastModified = gmdate('r', filemtime($fileName));
+			
+			// Generate E-Tag
+			$fileEtag = hash('sha256', $fileLastModified.$fileName);
+			
+			
+			// Set header
+			$this->response->addHeader("Last-Modified: ".$fileLastModified);
+			$this->response->addHeader("Etag: ".$fileEtag);
+			// HTTP-status
+			$headerModifiedSince = $this->request->getServerParam('HTTP_IF_MODIFIED_SINCE');
+			$headerNoneMatch = $this->request->getServerParam('HTTP_IF_NONE_MATCH');
+			if(
+				!is_null($headerModifiedSince) && $fileLastModified < strtotime($headerModifiedSince) &&
+				!is_null($headerNoneMatch) && $headerNoneMatch == $fileEtag
+			) {
+				$this->response->setExit(true);
+				$this->response->addHeader(\nre\core\WebUtils::getHttpHeader(304));
+				
+				return true;
+			}
+			
+			
+			return false;
+		}
+		
 	}
 
 ?>