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 defined('MOODLE_INTERNAL') || die();
  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     // 90 days only - based on Moodle point release cadence being every 3 months.
  38     $lifetime = 60 * 60 * 24 * 90;
  39
  40     header('Etag: "'.$etag.'"');
  41     header('Content-Disposition: inline; filename="'.$filename.'"');
  42     header('Last-Modified: '. gmdate('D, d M Y H:i:s', filemtime($jspath)) .' GMT');
  43     header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
  44     header('Pragma: ');
  45     header('Cache-Control: public, max-age='.$lifetime.', immutable');
  46     header('Accept-Ranges: none');
  47     header('Content-Type: application/javascript; charset=utf-8');
  48
  49     if (xsendfile($jspath)) {
  50         die;
  51     }
  52
  53     if (!min_enable_zlib_compression()) {
  54         header('Content-Length: '.filesize($jspath));
  55     }
  56
  57     readfile($jspath);
  58     die;
  59 }
  60
  61 /**
  62  * Send javascript without any caching
  63  * @param string $js
  64  * @param string $filename
  65  */
  66 function js_send_uncached($js, $filename = 'javascript.php') {
  67     header('Content-Disposition: inline; filename="'.$filename.'"');
  68     header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
  69     header('Expires: '. gmdate('D, d M Y H:i:s', time() + 2) .' GMT');
  70     header('Pragma: ');
  71     header('Accept-Ranges: none');
  72     header('Content-Type: application/javascript; charset=utf-8');
  73     header('Content-Length: '.strlen($js));
  74
  75     echo $js;
  76     die;
  77 }
  78
  79 /**
  80  * Send file not modified headers
  81  * @param int $lastmodified
  82  * @param string $etag
  83  */
  84 function js_send_unmodified($lastmodified, $etag) {
  85     // 90 days only - based on Moodle point release cadence being every 3 months.
  86     $lifetime = 60 * 60 * 24 * 90;
  87     header('HTTP/1.1 304 Not Modified');
  88     header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
  89     header('Cache-Control: public, max-age='.$lifetime);
  90     header('Content-Type: application/javascript; charset=utf-8');
  91     header('Etag: "'.$etag.'"');
  92     if ($lastmodified) {
  93         header('Last-Modified: '. gmdate('D, d M Y H:i:s', $lastmodified) .' GMT');
  94     }
  95     die;
  96 }
  97
  98 /**
  99  * Create cache file for JS content
 100  * @param string $file full file path to cache file
 101  * @param string $content JS code
 102  */
 103 function js_write_cache_file_content($file, $content) {
 104     global $CFG;
 105
 106     clearstatcache();
 107     if (!file_exists(dirname($file))) {
 108         @mkdir(dirname($file), $CFG->directorypermissions, true);
 109     }
 110
 111     // Prevent serving of incomplete file from concurrent request,
 112     // the rename() should be more atomic than fwrite().
 113     ignore_user_abort(true);
 114     if ($fp = fopen($file.'.tmp', 'xb')) {
 115         fwrite($fp, $content);
 116         fclose($fp);
 117         rename($file.'.tmp', $file);
 118         @chmod($file, $CFG->filepermissions);
 119         @unlink($file.'.tmp'); // just in case anything fails
 120     }
 121     ignore_user_abort(false);
 122     if (connection_aborted()) {
 123         die;
 124     }
 125 }
 126
 127 /**
 128  * Sends a 404 message about CSS not being found.
 129  */
 130 function js_send_css_not_found() {
 131     header('HTTP/1.0 404 not found');
 132     die('JS was not found, sorry.');
 133 }