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     $lifetime = 60*60*24*60; // 60 days only - the revision may get incremented quite often
  38
  39     header('Etag: "'.$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  * Create cache file for JS content
  98  * @param string $file full file path to cache file
  99  * @param string $content JS code
 100  */
 101 function js_write_cache_file_content($file, $content) {
 102     global $CFG;
 103
 104     clearstatcache();
 105     if (!file_exists(dirname($file))) {
 106         @mkdir(dirname($file), $CFG->directorypermissions, true);
 107     }
 108
 109     // Prevent serving of incomplete file from concurrent request,
 110     // the rename() should be more atomic than fwrite().
 111     ignore_user_abort(true);
 112     if ($fp = fopen($file.'.tmp', 'xb')) {
 113         fwrite($fp, $content);
 114         fclose($fp);
 115         rename($file.'.tmp', $file);
 116         @chmod($file, $CFG->filepermissions);
 117         @unlink($file.'.tmp'); // just in case anything fails
 118     }
 119     ignore_user_abort(false);
 120     if (connection_aborted()) {
 121         die;
 122     }
 123 }
 124
 125 /**
 126  * Sends a 404 message about CSS not being found.
 127  */
 128 function js_send_css_not_found() {
 129     header('HTTP/1.0 404 not found');
 130     die('JS was not found, sorry.');
 131 }