1: <?php
  2: 
  3: /**
  4:  * This file is part of the Nette Framework (https://nette.org)
  5:  * Copyright (c) 2004 David Grudl (https://davidgrudl.com)
  6:  */
  7: 
  8: namespace Nette\Http;
  9: 
 10: use Nette;
 11: 
 12: 
 13: /**
 14:  * HTTP-specific tasks.
 15:  */
 16: class Context extends Nette\Object
 17: {
 18:     /** @var IRequest */
 19:     private $request;
 20: 
 21:     /** @var IResponse */
 22:     private $response;
 23: 
 24: 
 25:     public function __construct(IRequest $request, IResponse $response)
 26:     {
 27:         $this->request = $request;
 28:         $this->response = $response;
 29:     }
 30: 
 31: 
 32:     /**
 33:      * Attempts to cache the sent entity by its last modification date.
 34:      * @param  string|int|\DateTime  last modified time
 35:      * @param  string  strong entity tag validator
 36:      * @return bool
 37:      */
 38:     public function isModified($lastModified = NULL, $etag = NULL)
 39:     {
 40:         if ($lastModified) {
 41:             $this->response->setHeader('Last-Modified', Helpers::formatDate($lastModified));
 42:         }
 43:         if ($etag) {
 44:             $this->response->setHeader('ETag', '"' . addslashes($etag) . '"');
 45:         }
 46: 
 47:         $ifNoneMatch = $this->request->getHeader('If-None-Match');
 48:         if ($ifNoneMatch === '*') {
 49:             $match = TRUE; // match, check if-modified-since
 50: 
 51:         } elseif ($ifNoneMatch !== NULL) {
 52:             $etag = $this->response->getHeader('ETag');
 53: 
 54:             if ($etag == NULL || strpos(' ' . strtr($ifNoneMatch, ",\t", '  '), ' ' . $etag) === FALSE) {
 55:                 return TRUE;
 56: 
 57:             } else {
 58:                 $match = TRUE; // match, check if-modified-since
 59:             }
 60:         }
 61: 
 62:         $ifModifiedSince = $this->request->getHeader('If-Modified-Since');
 63:         if ($ifModifiedSince !== NULL) {
 64:             $lastModified = $this->response->getHeader('Last-Modified');
 65:             if ($lastModified != NULL && strtotime($lastModified) <= strtotime($ifModifiedSince)) {
 66:                 $match = TRUE;
 67: 
 68:             } else {
 69:                 return TRUE;
 70:             }
 71:         }
 72: 
 73:         if (empty($match)) {
 74:             return TRUE;
 75:         }
 76: 
 77:         $this->response->setCode(IResponse::S304_NOT_MODIFIED);
 78:         return FALSE;
 79:     }
 80: 
 81: 
 82:     /**
 83:      * @return IRequest
 84:      */
 85:     public function getRequest()
 86:     {
 87:         return $this->request;
 88:     }
 89: 
 90: 
 91:     /**
 92:      * @return IResponse
 93:      */
 94:     public function getResponse()
 95:     {
 96:         return $this->response;
 97:     }
 98: 
 99: }
100: