theme/image.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * This file is responsible for serving the one theme and plugin images.
  20  *
  21  * @package   moodlecore
  22  * @copyright 2009 Petr Skoda (skodak)  {@link http://skodak.org}
  23  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  */
  25
  26
  27 // disable moodle specific debug messages and any errors in output,
  28 // comment out when debugging or better look into error log!
  29 define('NO_DEBUG_DISPLAY', true);
  30
  31 // we need just the values from config.php and minlib.php
  32 define('ABORT_AFTER_CONFIG', true);
  33 require('../config.php'); // this stops immediately at the beginning of lib/setup.php
  34
  35 $themename = min_optional_param('theme', 'standard', 'SAFEDIR');
  36 $component = min_optional_param('component', 'moodle', 'SAFEDIR');
  37 $image     = min_optional_param('image', '', 'SAFEPATH');
  38 $rev       = min_optional_param('rev', -1, 'INT');
  39
  40 if (empty($component) or empty($image)) {
  41     image_not_found();
  42 }
  43
  44 if (file_exists("$CFG->dirroot/theme/$themename/config.php")) {
  45     // exists
  46 } else if (!empty($CFG->themedir) and file_exists("$CFG->themedir/$themename/config.php")) {
  47     // exists
  48 } else {
  49     image_not_found();
  50 }
  51
  52 $candidatelocation = "$CFG->cachedir/theme/$themename/pix/$component";
  53
  54 if ($rev > -1) {
  55     if (file_exists("$candidatelocation/$image.error")) {
  56         // this is a major speedup if there are multiple missing images,
  57         // the only problem is that random requests may pollute our cache.
  58         image_not_found();
  59     }
  60     $cacheimage = false;
  61     if (file_exists("$candidatelocation/$image.gif")) {
  62         $cacheimage = "$candidatelocation/$image.gif";
  63         $ext = 'gif';
  64     } else if (file_exists("$candidatelocation/$image.png")) {
  65         $cacheimage = "$candidatelocation/$image.png";
  66         $ext = 'png';
  67     } else if (file_exists("$candidatelocation/$image.jpg")) {
  68         $cacheimage = "$candidatelocation/$image.jpg";
  69         $ext = 'jpg';
  70     } else if (file_exists("$candidatelocation/$image.jpeg")) {
  71         $cacheimage = "$candidatelocation/$image.jpeg";
  72         $ext = 'jpeg';
  73     } else if (file_exists("$candidatelocation/$image.ico")) {
  74         $cacheimage = "$candidatelocation/$image.ico";
  75         $ext = 'ico';
  76     }
  77     if ($cacheimage) {
  78         if (!empty($_SERVER['HTTP_IF_NONE_MATCH']) || !empty($_SERVER['HTTP_IF_MODIFIED_SINCE'])) {
  79             // we do not actually need to verify the etag value because our files
  80             // never change in cache because we increment the rev parameter
  81             $lifetime = 60*60*24*30; // 30 days
  82             $mimetype = get_contenttype_from_ext($ext);
  83             header('HTTP/1.1 304 Not Modified');
  84             header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
  85             header('Cache-Control: max-age='.$lifetime);
  86             header('Content-Type: '.$mimetype);
  87             die;
  88         }
  89         send_cached_image($cacheimage, $rev);
  90     }
  91 }
  92
  93 //=================================================================================
  94 // ok, now we need to start normal moodle script, we need to load all libs and $DB
  95 define('ABORT_AFTER_CONFIG_CANCEL', true);
  96
  97 define('NO_MOODLE_COOKIES', true); // Session not used here
  98 define('NO_UPGRADE_CHECK', true);  // Ignore upgrade check
  99
 100 require("$CFG->dirroot/lib/setup.php");
 101
 102 $theme = theme_config::load($themename);
 103 $imagefile = $theme->resolve_image_location($image, $component);
 104
 105 $rev = theme_get_revision();
 106
 107 if (empty($imagefile) or !is_readable($imagefile)) {
 108     if ($rev > -1) {
 109         // make note we can not find this file
 110         $cacheimage = "$candidatelocation/$image.error";
 111         $fp = fopen($cacheimage, 'w');
 112         fclose($fp);
 113     }
 114     image_not_found();
 115 }
 116
 117
 118 if ($rev > -1) {
 119     $pathinfo = pathinfo($imagefile);
 120     $cacheimage = "$candidatelocation/$image.".$pathinfo['extension'];
 121     if (!file_exists($cacheimage)) {
 122         // note: cache reset might have purged our cache dir structure,
 123         //       make sure we do not use stale file stat cache in the next check_dir_exists()
 124         clearstatcache();
 125         check_dir_exists(dirname($cacheimage));
 126         copy($imagefile, $cacheimage);
 127     }
 128     send_cached_image($cacheimage, $rev);
 129
 130 } else {
 131     send_uncached_image($imagefile);
 132 }
 133
 134
 135 //=================================================================================
 136 //=== utility functions ==
 137 // we are not using filelib because we need to fine tune all header
 138 // parameters to get the best performance.
 139
 140 function send_cached_image($imagepath, $rev) {
 141     $lifetime = 60*60*24*30; // 30 days
 142     $pathinfo = pathinfo($imagepath);
 143     $imagename = $pathinfo['filename'].'.'.$pathinfo['extension'];
 144
 145     $mimetype = get_contenttype_from_ext($pathinfo['extension']);
 146
 147     header('Etag: '.md5("$rev/$imagepath"));
 148     header('Content-Disposition: inline; filename="'.$imagename.'"');
 149     header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
 150     header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
 151     header('Pragma: ');
 152     header('Cache-Control: max-age='.$lifetime);
 153     header('Accept-Ranges: none');
 154     header('Content-Type: '.$mimetype);
 155     header('Content-Length: '.filesize($imagepath));
 156
 157     // no need to gzip already compressed images ;-)
 158
 159     readfile($imagepath);
 160     die;
 161 }
 162
 163 function send_uncached_image($imagepath) {
 164     $pathinfo = pathinfo($imagepath);
 165     $imagename = $pathinfo['filename'].'.'.$pathinfo['extension'];
 166
 167     $mimetype = get_contenttype_from_ext($pathinfo['extension']);
 168
 169     header('Content-Disposition: inline; filename="'.$imagename.'"');
 170     header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
 171     header('Expires: '. gmdate('D, d M Y H:i:s', time() + 15) .' GMT');
 172     header('Pragma: ');
 173     header('Accept-Ranges: none');
 174     header('Content-Type: '.$mimetype);
 175     header('Content-Length: '.filesize($imagepath));
 176
 177     readfile($imagepath);
 178     die;
 179 }
 180
 181 function image_not_found() {
 182     header('HTTP/1.0 404 not found');
 183     die('Image was not found, sorry.');
 184 }
 185
 186 function get_contenttype_from_ext($ext) {
 187     switch ($ext) {
 188         case 'gif':
 189             return 'image/gif';
 190         case 'png':
 191             return 'image/png';
 192         case 'jpg':
 193         case 'jpeg':
 194             return 'image/jpeg';
 195         case 'ico':
 196             return 'image/vnd.microsoft.icon';
 197     }
 198     return 'document/unknown';
 199 }