resources/src/startup.js

   1 /**
   2  * Code in this file MUST work on even the most ancient of browsers!
   3  *
   4  * This file is where we decide whether to initialise the modern run-time.
   5  */
   6
   7 /* global mw, $VARS, $CODE */
   8
   9 // eslint-disable-next-line no-unused-vars
  10 var mediaWikiLoadStart = ( new Date() ).getTime(),
  11         mwPerformance = ( window.performance && performance.mark ) ? performance : {
  12                 mark: function () {}
  13         };
  14
  15 mwPerformance.mark( 'mwLoadStart' );
  16
  17 /**
  18  * See <https://www.mediawiki.org/wiki/Compatibility#Browsers>
  19  *
  20  * Capabilities required for modern run-time:
  21  * - DOM Level 4 & Selectors API Level 1
  22  * - HTML5 & Web Storage
  23  * - DOM Level 2 Events
  24  * - JSON
  25  *
  26  * Browsers we support in our modern run-time (Grade A):
  27  * - Chrome 4+
  28  * - IE 9+
  29  * - Firefox 3.5+
  30  * - Safari 5+
  31  * - Opera 10.5+
  32  * - Mobile Safari (iOS 4+)
  33  * - Android 2.0+
  34  *
  35  * Browsers we support in our no-javascript run-time (Grade C):
  36  * - Chrome 1+
  37  * - IE 6+
  38  * - Firefox 3+
  39  * - Safari 3+
  40  * - Opera 10+
  41  * - WebOS < 1.5
  42  * - PlayStation
  43  * - Symbian-based browsers
  44  * - NetFront-based browser
  45  * - Opera Mini
  46  * - Nokia's Ovi Browser
  47  * - MeeGo's browser
  48  * - Google Glass
  49  * - UC Mini (speed mode on)
  50  *
  51  * Other browsers that pass the check are considered Grade X.
  52  *
  53  * @param {string} [str] User agent, defaults to navigator.userAgent
  54  * @return {boolean} User agent is compatible with MediaWiki JS
  55  */
  56 function isCompatible( str ) {
  57         var ua = str || navigator.userAgent;
  58         return !!(
  59                 // http://caniuse.com/#feat=queryselector
  60                 'querySelector' in document &&
  61
  62                 // http://caniuse.com/#feat=namevalue-storage
  63                 // https://developer.blackberry.com/html5/apis/v1_0/localstorage.html
  64                 // https://blog.whatwg.org/this-week-in-html-5-episode-30
  65                 'localStorage' in window &&
  66
  67                 // http://caniuse.com/#feat=addeventlistener
  68                 'addEventListener' in window &&
  69
  70                 // http://caniuse.com/#feat=json
  71                 // https://phabricator.wikimedia.org/T141344#2784065
  72                 ( window.JSON && JSON.stringify && JSON.parse ) &&
  73
  74                 // Hardcoded exceptions for browsers that pass the requirement but we don't want to
  75                 // support in the modern run-time.
  76                 // Note: Please extend the regex instead of adding new ones
  77                 !(
  78                         ua.match( /webOS\/1\.[0-4]|SymbianOS|Series60|NetFront|Opera Mini|S40OviBrowser|MeeGo|Android.+Glass|^Mozilla\/5\.0 .+ Gecko\/$|googleweblight/ ) ||
  79                         ua.match( /PlayStation/i )
  80                 )
  81         );
  82 }
  83
  84 // Conditional script injection
  85 ( function () {
  86         var NORLQ, script;
  87         if ( !isCompatible() ) {
  88                 // Undo class swapping in case of an unsupported browser.
  89                 // See ResourceLoaderClientHtml::getDocumentAttributes().
  90                 document.documentElement.className = document.documentElement.className
  91                         .replace( /(^|\s)client-js(\s|$)/, '$1client-nojs$2' );
  92
  93                 NORLQ = window.NORLQ || [];
  94                 while ( NORLQ.length ) {
  95                         NORLQ.shift()();
  96                 }
  97                 window.NORLQ = {
  98                         push: function ( fn ) {
  99                                 fn();
 100                         }
 101                 };
 102
 103                 // Clear and disable the other queue
 104                 window.RLQ = {
 105                         // No-op
 106                         push: function () {}
 107                 };
 108
 109                 return;
 110         }
 111
 112         /**
 113          * The $CODE and $VARS placeholders are substituted in ResourceLoaderStartUpModule.php.
 114          */
 115         function startUp() {
 116                 mw.config = new mw.Map( $VARS.wgLegacyJavaScriptGlobals );
 117
 118                 $CODE.registrations();
 119
 120                 mw.config.set( $VARS.configuration );
 121
 122                 // Must be after mw.config.set because these callbacks may use mw.loader which
 123                 // needs to have values 'skin', 'debug' etc. from mw.config.
 124                 // eslint-disable-next-line vars-on-top
 125                 var RLQ = window.RLQ || [];
 126                 while ( RLQ.length ) {
 127                         RLQ.shift()();
 128                 }
 129                 window.RLQ = {
 130                         push: function ( fn ) {
 131                                 fn();
 132                         }
 133                 };
 134
 135                 // Clear and disable the other queue
 136                 window.NORLQ = {
 137                         // No-op
 138                         push: function () {}
 139                 };
 140         }
 141
 142         script = document.createElement( 'script' );
 143         script.src = $VARS.baseModulesUri;
 144         script.onload = script.onreadystatechange = function () {
 145                 if ( !script.readyState || /loaded|complete/.test( script.readyState ) ) {
 146                         // Clean up
 147                         script.onload = script.onreadystatechange = null;
 148                         script = null;
 149                         // Callback
 150                         startUp();
 151                 }
 152         };
 153         document.getElementsByTagName( 'head' )[ 0 ].appendChild( script );
 154 }() );