1: <?php
  2: 
  3: /**
  4:  * This file is part of the Nette Framework (https://nette.org)
  5:  * Copyright (c) 2004 David Grudl (http://davidgrudl.com)
  6:  */
  7: 
  8: namespace Nette\Http;
  9: 
 10: use Nette;
 11: 
 12: 
 13: /**
 14:  * HTTP-specific tasks.
 15:  *
 16:  * @author     David Grudl
 17:  *
 18:  * @property-read bool $modified
 19:  * @property-read IRequest $request
 20:  * @property-read IResponse $response
 21:  */
 22: class Context extends Nette\Object
 23: {
 24:     /** @var IRequest */
 25:     private $request;
 26: 
 27:     /** @var IResponse */
 28:     private $response;
 29: 
 30: 
 31:     public function __construct(IRequest $request, IResponse $response)
 32:     {
 33:         $this->request = $request;
 34:         $this->response = $response;
 35:     }
 36: 
 37: 
 38:     /**
 39:      * Attempts to cache the sent entity by its last modification date.
 40:      * @param  string|int|DateTime  last modified time
 41:      * @param  string  strong entity tag validator
 42:      * @return bool
 43:      */
 44:     public function isModified($lastModified = NULL, $etag = NULL)
 45:     {
 46:         if ($lastModified) {
 47:             $this->response->setHeader('Last-Modified', $this->response->date($lastModified));
 48:         }
 49:         if ($etag) {
 50:             $this->response->setHeader('ETag', '"' . addslashes($etag) . '"');
 51:         }
 52: 
 53:         $ifNoneMatch = $this->request->getHeader('If-None-Match');
 54:         if ($ifNoneMatch === '*') {
 55:             $match = TRUE; // match, check if-modified-since
 56: 
 57:         } elseif ($ifNoneMatch !== NULL) {
 58:             $etag = $this->response->getHeader('ETag');
 59: 
 60:             if ($etag == NULL || strpos(' ' . strtr($ifNoneMatch, ",\t", '  '), ' ' . $etag) === FALSE) {
 61:                 return TRUE;
 62: 
 63:             } else {
 64:                 $match = TRUE; // match, check if-modified-since
 65:             }
 66:         }
 67: 
 68:         $ifModifiedSince = $this->request->getHeader('If-Modified-Since');
 69:         if ($ifModifiedSince !== NULL) {
 70:             $lastModified = $this->response->getHeader('Last-Modified');
 71:             if ($lastModified != NULL && strtotime($lastModified) <= strtotime($ifModifiedSince)) {
 72:                 $match = TRUE;
 73: 
 74:             } else {
 75:                 return TRUE;
 76:             }
 77:         }
 78: 
 79:         if (empty($match)) {
 80:             return TRUE;
 81:         }
 82: 
 83:         $this->response->setCode(IResponse::S304_NOT_MODIFIED);
 84:         return FALSE;
 85:     }
 86: 
 87: 
 88:     /**
 89:      * @return IRequest
 90:      */
 91:     public function getRequest()
 92:     {
 93:         return $this->request;
 94:     }
 95: 
 96: 
 97:     /**
 98:      * @return IResponse
 99:      */
100:     public function getResponse()
101:     {
102:         return $this->response;
103:     }
104: 
105: }
106: