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 // we need just the values from config.php and minlib.php
  28 define('ABORT_AFTER_CONFIG', true);
  29 require('../config.php'); // this stops immediately at the beginning of lib/setup.php
  30
  31 $themename = min_optional_param('theme', 'standard', 'SAFEDIR');
  32 $component = min_optional_param('component', 'moodle', 'SAFEDIR');
  33 $image     = min_optional_param('image', '', 'SAFEPATH');
  34 $rev       = min_optional_param('rev', -1, 'INT');
  35
  36 if (empty($component) or empty($image)) {
  37     image_not_found();
  38 }
  39
  40 if (file_exists("$CFG->dirroot/theme/$themename/config.php")) {
  41     // exists
  42 } else if (!empty($CFG->themedir) and file_exists("$CFG->themedir/$themename/config.php")) {
  43     // exists
  44 } else {
  45     image_not_found();
  46 }
  47
  48 $candidatelocation = "$CFG->cachedir/theme/$themename/pix/$component";
  49
  50 if ($rev > -1) {
  51     if (file_exists("$candidatelocation/$image.error")) {
  52         // this is a major speedup if there are multiple missing images,
  53         // the only problem is that random requests may pollute our cache.
  54         image_not_found();
  55     }
  56     $cacheimage = false;
  57     if (file_exists("$candidatelocation/$image.gif")) {
  58         $cacheimage = "$candidatelocation/$image.gif";
  59         $ext = 'gif';
  60     } else if (file_exists("$candidatelocation/$image.png")) {
  61         $cacheimage = "$candidatelocation/$image.png";
  62         $ext = 'png';
  63     } else if (file_exists("$candidatelocation/$image.jpg")) {
  64         $cacheimage = "$candidatelocation/$image.jpg";
  65         $ext = 'jpg';
  66     } else if (file_exists("$candidatelocation/$image.jpeg")) {
  67         $cacheimage = "$candidatelocation/$image.jpeg";
  68         $ext = 'jpeg';
  69     } else if (file_exists("$candidatelocation/$image.ico")) {
  70         $cacheimage = "$candidatelocation/$image.ico";
  71         $ext = 'ico';
  72     }
  73     if ($cacheimage) {
  74         if (!empty($_SERVER['HTTP_IF_NONE_MATCH']) || !empty($_SERVER['HTTP_IF_MODIFIED_SINCE'])) {
  75             // we do not actually need to verify the etag value because our files
  76             // never change in cache because we increment the rev parameter
  77             $lifetime = 60*60*24*30; // 30 days
  78             $mimetype = get_contenttype_from_ext($ext);
  79             header('HTTP/1.1 304 Not Modified');
  80             header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
  81             header('Cache-Control: max-age='.$lifetime);
  82             header('Content-Type: '.$mimetype);
  83             die;
  84         }
  85         send_cached_image($cacheimage, $rev);
  86     }
  87 }
  88
  89 //=================================================================================
  90 // ok, now we need to start normal moodle script, we need to load all libs and $DB
  91 define('ABORT_AFTER_CONFIG_CANCEL', true);
  92
  93 define('NO_MOODLE_COOKIES', true); // Session not used here
  94 define('NO_UPGRADE_CHECK', true);  // Ignore upgrade check
  95
  96 require("$CFG->dirroot/lib/setup.php");
  97
  98 $theme = theme_config::load($themename);
  99 $imagefile = $theme->resolve_image_location($image, $component);
 100
 101 $rev = theme_get_revision();
 102
 103 if (empty($imagefile) or !is_readable($imagefile)) {
 104     if ($rev > -1) {
 105         // make note we can not find this file
 106         $cacheimage = "$candidatelocation/$image.error";
 107         $fp = fopen($cacheimage, 'w');
 108         fclose($fp);
 109     }
 110     image_not_found();
 111 }
 112
 113
 114 if ($rev > -1) {
 115     $pathinfo = pathinfo($imagefile);
 116     $cacheimage = "$candidatelocation/$image.".$pathinfo['extension'];
 117     if (!file_exists($cacheimage)) {
 118         check_dir_exists(dirname($cacheimage));
 119         copy($imagefile, $cacheimage);
 120     }
 121     send_cached_image($cacheimage, $rev);
 122
 123 } else {
 124     send_uncached_image($imagefile);
 125 }
 126
 127
 128 //=================================================================================
 129 //=== utility functions ==
 130 // we are not using filelib because we need to fine tune all header
 131 // parameters to get the best performance.
 132
 133 function send_cached_image($imagepath, $rev) {
 134     $lifetime = 60*60*24*30; // 30 days
 135     $pathinfo = pathinfo($imagepath);
 136     $imagename = $pathinfo['filename'].'.'.$pathinfo['extension'];
 137
 138     $mimetype = get_contenttype_from_ext($pathinfo['extension']);
 139
 140     header('Etag: '.md5("$rev/$imagepath"));
 141     header('Content-Disposition: inline; filename="'.$imagename.'"');
 142     header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
 143     header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
 144     header('Pragma: ');
 145     header('Cache-Control: max-age='.$lifetime);
 146     header('Accept-Ranges: none');
 147     header('Content-Type: '.$mimetype);
 148     header('Content-Length: '.filesize($imagepath));
 149
 150     // no need to gzip already compressed images ;-)
 151
 152     readfile($imagepath);
 153     die;
 154 }
 155
 156 function send_uncached_image($imagepath) {
 157     $pathinfo = pathinfo($imagepath);
 158     $imagename = $pathinfo['filename'].'.'.$pathinfo['extension'];
 159
 160     $mimetype = get_contenttype_from_ext($pathinfo['extension']);
 161
 162     header('Content-Disposition: inline; filename="'.$imagename.'"');
 163     header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
 164     header('Expires: '. gmdate('D, d M Y H:i:s', time() + 15) .' GMT');
 165     header('Pragma: ');
 166     header('Accept-Ranges: none');
 167     header('Content-Type: '.$mimetype);
 168     header('Content-Length: '.filesize($imagepath));
 169
 170     readfile($imagepath);
 171     die;
 172 }
 173
 174 function image_not_found() {
 175     header('HTTP/1.0 404 not found');
 176     die('Image was not found, sorry.');
 177 }
 178
 179 function get_contenttype_from_ext($ext) {
 180     switch ($ext) {
 181         case 'gif':
 182             return 'image/gif';
 183         case 'png':
 184             return 'image/png';
 185         case 'jpg':
 186         case 'jpeg':
 187             return 'image/jpeg';
 188         case 'ico':
 189             return 'image/vnd.microsoft.icon';
 190     }
 191     return 'document/unknown';
 192 }