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