lib/jslib.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * This file contains various javascript related functions,
  19  * all functions here are self contained and can be used in ABORT_AFTER_CONFIG scripts.
  20  *
  21  * @package   core_lib
  22  * @copyright 2012 Petr Skoda (skodak)  {@link http://skodak.org}
  23  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  */
  25
  26 //NOTE: do not verify MOODLE_INTERNAL here, this is used from themes too
  27
  28 /**
  29  * Send javascript file content with as much caching as possible
  30  * @param string $jspath
  31  * @param string $etag
  32  * @param string $filename
  33  */
  34 function js_send_cached($jspath, $etag, $filename = 'javascript.php') {
  35     require(__DIR__ . '/xsendfilelib.php');
  36
  37     $lifetime = 60*60*24*60; // 60 days only - the revision may get incremented quite often
  38
  39     header('Etag: '.$etag);
  40     header('Content-Disposition: inline; filename="'.$filename.'"');
  41     header('Last-Modified: '. gmdate('D, d M Y H:i:s', filemtime($jspath)) .' GMT');
  42     header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
  43     header('Pragma: ');
  44     header('Cache-Control: public, max-age='.$lifetime);
  45     header('Accept-Ranges: none');
  46     header('Content-Type: application/javascript; charset=utf-8');
  47
  48     if (xsendfile($jspath)) {
  49         die;
  50     }
  51
  52     if (!min_enable_zlib_compression()) {
  53         header('Content-Length: '.filesize($jspath));
  54     }
  55
  56     readfile($jspath);
  57     die;
  58 }
  59
  60 /**
  61  * Send javascript without any caching
  62  * @param string $js
  63  * @param string $filename
  64  */
  65 function js_send_uncached($js, $filename = 'javascript.php') {
  66     header('Content-Disposition: inline; filename="'.$filename.'"');
  67     header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
  68     header('Expires: '. gmdate('D, d M Y H:i:s', time() + 2) .' GMT');
  69     header('Pragma: ');
  70     header('Accept-Ranges: none');
  71     header('Content-Type: application/javascript; charset=utf-8');
  72     header('Content-Length: '.strlen($js));
  73
  74     echo $js;
  75     die;
  76 }
  77
  78 /**
  79  * Send file not modified headers
  80  * @param int $lastmodified
  81  * @param string $etag
  82  */
  83 function js_send_unmodified($lastmodified, $etag) {
  84     $lifetime = 60*60*24*60; // 60 days only - the revision may get incremented quite often
  85     header('HTTP/1.1 304 Not Modified');
  86     header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
  87     header('Cache-Control: public, max-age='.$lifetime);
  88     header('Content-Type: application/javascript; charset=utf-8');
  89     header('Etag: '.$etag);
  90     if ($lastmodified) {
  91         header('Last-Modified: '. gmdate('D, d M Y H:i:s', $lastmodified) .' GMT');
  92     }
  93     die;
  94 }
  95
  96 /**
  97  * Minify javascript files
  98  * @param array $files
  99  * @return string
 100  */
 101 function js_minify($files) {
 102     // setup include path
 103     set_include_path(__DIR__ . '/minify/lib' . PATH_SEPARATOR . get_include_path());
 104     require_once('Minify.php');
 105
 106     if (empty($files)) {
 107         return '';
 108     }
 109
 110     if (0 === stripos(PHP_OS, 'win')) {
 111         Minify::setDocRoot(); // IIS may need help
 112     }
 113     // disable all caching, we do it in moodle
 114     Minify::setCache(null, false);
 115
 116     $options = array(
 117         // JSMin is not GNU GPL compatible, use the plus version instead.
 118         'minifiers' => array(Minify::TYPE_JS => array('JSMinPlus', 'minify')),
 119         'bubbleCssImports' => false,
 120         // Don't gzip content we just want text for storage
 121         'encodeOutput' => false,
 122         // Maximum age to cache, not used but required
 123         'maxAge' => 1800,
 124         // The files to minify
 125         'files' => $files,
 126         // Turn orr URI rewriting
 127         'rewriteCssUris' => false,
 128         // This returns the CSS rather than echoing it for display
 129         'quiet' => true
 130     );
 131
 132     $error = 'unknown';
 133     try {
 134         $result = Minify::serve('Files', $options);
 135         if ($result['success']) {
 136             return $result['content'];
 137         }
 138     } catch (Exception $e) {
 139         $error = $e->getMessage();
 140         $error = str_replace("\r", ' ', $error);
 141         $error = str_replace("\n", ' ', $error);
 142     }
 143
 144     // minification failed - try to inform the theme developer and include the non-minified version
 145     $js = <<<EOD
 146 try {console.log('Error: Minimisation of javascript failed!');} catch (e) {}
 147
 148 // Error: $error
 149 // Problem detected during javascript minimisation, please review the following code
 150 // =================================================================================
 151
 152
 153 EOD;
 154     foreach ($files as $jsfile) {
 155         $js .= file_get_contents($jsfile)."\n";
 156     }
 157     return $js;
 158 }
 159
 160 /**
 161  * Create cache file for JS content
 162  * @param string $file full file path to cache file
 163  * @param string $content JS code
 164  */
 165 function js_write_cache_file_content($file, $content) {
 166     global $CFG;
 167
 168     clearstatcache();
 169     if (!file_exists(dirname($file))) {
 170         @mkdir(dirname($file), $CFG->directorypermissions, true);
 171     }
 172
 173     // Prevent serving of incomplete file from concurrent request,
 174     // the rename() should be more atomic than fwrite().
 175     ignore_user_abort(true);
 176     if ($fp = fopen($file.'.tmp', 'xb')) {
 177         fwrite($fp, $content);
 178         fclose($fp);
 179         rename($file.'.tmp', $file);
 180         @chmod($file, $CFG->filepermissions);
 181         @unlink($file.'.tmp'); // just in case anything fails
 182     }
 183     ignore_user_abort(false);
 184     if (connection_aborted()) {
 185         die;
 186     }
 187 }
 188
 189 /**
 190  * Sends a 404 message about CSS not being found.
 191  */
 192 function js_send_css_not_found() {
 193     header('HTTP/1.0 404 not found');
 194     die('JS was not found, sorry.');
 195 }