lib/requirejs.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 is serving optimised JS for RequireJS.
  19  *
  20  * @package    core
  21  * @copyright  2015 Damyon Wiese
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 // Disable moodle specific debug messages and any errors in output,
  26 // comment out when debugging or better look into error log!
  27 define('NO_DEBUG_DISPLAY', true);
  28
  29 // We need just the values from config.php and minlib.php.
  30 define('ABORT_AFTER_CONFIG', true);
  31 require('../config.php'); // This stops immediately at the beginning of lib/setup.php.
  32 require_once("$CFG->dirroot/lib/jslib.php");
  33 require_once("$CFG->dirroot/lib/classes/requirejs.php");
  34
  35 $slashargument = min_get_slash_argument();
  36 if (!$slashargument) {
  37     // The above call to min_get_slash_argument should always work.
  38     die('Invalid request');
  39 }
  40
  41 $slashargument = ltrim($slashargument, '/');
  42 if (substr_count($slashargument, '/') < 1) {
  43     header('HTTP/1.0 404 not found');
  44     die('Slash argument must contain both a revision and a file path');
  45 }
  46 // Split into revision and module name.
  47 list($rev, $file) = explode('/', $slashargument, 2);
  48 $rev  = min_clean_param($rev, 'INT');
  49 $file = '/' . min_clean_param($file, 'SAFEPATH');
  50
  51 // Only load js files from the js modules folder from the components.
  52 $jsfiles = array();
  53 list($unused, $component, $module) = explode('/', $file, 3);
  54
  55 /**
  56  * Helper function to fix missing module names in JavaScript.
  57  *
  58  * TODO Remove this function when we find a reliable way to do this in the Grunt task.
  59  * @param string $modulename
  60  * @param string $js
  61  * @return string The modified JavaScript.
  62  */
  63 function requirejs_fix_define(string $modulename, string $js): string {
  64     // First check whether there is a possible missing module name. That is:
  65     // define (function(Foo) {
  66     // instead of:
  67     // define('mod_foo/bar', function(Foo) {
  68     $missingmodule = preg_match('/define\(\s*(\[|function)/', $js);
  69
  70     // Now check whether the module name is already defined elsewhere.
  71     // This could be a totally unrelated use of the word define.
  72     // Note: This code needs to die, in a fire. It is evil and wrong.
  73     $missingmodule = $missingmodule && !preg_match("@define\s*\(\s*['\"]{$modulename}['\"]@", $js);
  74
  75     if ($missingmodule) {
  76         // If the JavaScript module has been defined without specifying a name then we'll
  77         // add the Moodle module name now.
  78         $replace = 'define(\'' . $modulename . '\', ';
  79
  80         // Replace only the first occurrence.
  81         return implode($replace, explode('define(', $js, 2));
  82     } else if (!preg_match('/define\s*\(/', $js)) {
  83         echo(
  84             "// JS module '{$modulename}' cannot be loaded, or does not contain a javascript" .
  85             ' module in AMD format. "define()" not found.' . "\n"
  86         );
  87     }
  88
  89     return $js;
  90 }
  91
  92 // Use the caching only for meaningful revision numbers which prevents future cache poisoning.
  93 if ($rev > 0 and $rev < (time() + 60 * 60)) {
  94     // This is "production mode".
  95     // Some (huge) modules are better loaded lazily (when they are used). If we are requesting
  96     // one of these modules, only return the one module, not the combo.
  97     $lazysuffix = "-lazy.js";
  98     $lazyload = (strpos($module, $lazysuffix) !== false);
  99
 100     if ($lazyload) {
 101         // We are lazy loading a single file - so include the component/filename pair in the etag.
 102         $etag = sha1($rev . '/' . $component . '/' . $module);
 103     } else {
 104         // We loading all (non-lazy) files - so only the rev makes this request unique.
 105         $etag = sha1($rev);
 106     }
 107
 108     $candidate = $CFG->localcachedir . '/requirejs/' . $etag;
 109
 110     if (file_exists($candidate)) {
 111         if (!empty($_SERVER['HTTP_IF_NONE_MATCH']) || !empty($_SERVER['HTTP_IF_MODIFIED_SINCE'])) {
 112             // We do not actually need to verify the etag value because our files
 113             // never change in cache because we increment the rev parameter.
 114             js_send_unmodified(filemtime($candidate), $etag);
 115         }
 116         js_send_cached($candidate, $etag, 'requirejs.php');
 117         exit(0);
 118
 119     } else {
 120         $jsfiles = array();
 121         if ($lazyload) {
 122             $jsfiles = core_requirejs::find_one_amd_module($component, $module);
 123         } else {
 124             // Here we respond to the request by returning ALL amd modules. This saves
 125             // round trips in production.
 126
 127             $jsfiles = core_requirejs::find_all_amd_modules();
 128         }
 129
 130         $content = '';
 131         foreach ($jsfiles as $modulename => $jsfile) {
 132             $js = file_get_contents($jsfile);
 133             if ($js === false) {
 134                 error_log('Failed to load JavaScript file ' . $jsfile);
 135                 $js = "/* Failed to load JavaScript file {$jsfile}. */\n";
 136                 $content = $js . $content;
 137                 continue;
 138             }
 139             // Remove source map link.
 140             $js = preg_replace('~//# sourceMappingURL.*$~s', '', $js);
 141             $js = rtrim($js);
 142             $js .= "\n";
 143
 144             $js = requirejs_fix_define($modulename, $js);
 145
 146             $content .= $js;
 147         }
 148
 149         js_write_cache_file_content($candidate, $content);
 150         // Verify nothing failed in cache file creation.
 151         clearstatcache();
 152         if (file_exists($candidate)) {
 153             js_send_cached($candidate, $etag, 'requirejs.php');
 154             exit(0);
 155         }
 156     }
 157 }
 158
 159 // If we've made it here then we're in "dev mode" where everything is lazy loaded.
 160 // So all files will be served one at a time.
 161 $jsfiles = core_requirejs::find_one_amd_module($component, $module);
 162
 163 if (!empty($jsfiles)) {
 164     $modulename = array_keys($jsfiles)[0];
 165     $jsfile = $jsfiles[$modulename];
 166     $shortfilename = str_replace($CFG->dirroot, '', $jsfile);
 167     $mapfile = $jsfile . '.map';
 168
 169     if (file_exists($mapfile)) {
 170         // We've got a a source map file so we can return the minified file here and
 171         // the source map will be used by the browser to debug.
 172         $js = file_get_contents($jsfile);
 173         // Fix the source map link for the file.
 174         $js = preg_replace(
 175             '~//# sourceMappingURL.*$~s',
 176             "//# sourceMappingURL={$CFG->wwwroot}/lib/jssourcemap.php{$file}",
 177             $js
 178         );
 179         $js = rtrim($js);
 180     } else {
 181         // This file doesn't have a map file. We might be dealing with an older source file from
 182         // a plugin or previous version of Moodle so we should just return the full original source
 183         // like we used to.
 184         $originalsource = str_replace('/amd/build/', '/amd/src/', $jsfile);
 185         $originalsource = str_replace('.min.js', '.js', $originalsource);
 186         $js = file_get_contents($originalsource);
 187         $js = rtrim($js);
 188     }
 189
 190     $js = requirejs_fix_define($modulename, $js);
 191
 192     js_send_uncached($js, 'requirejs.php');
 193 } else {
 194     // We can't find the requested file.
 195     header('HTTP/1.0 404 not found');
 196 }