resources/src/startup.js

   1 /**
   2  * This script provides a function which is run to evaluate whether or not to
   3  * continue loading jQuery and the MediaWiki modules. This code should work on
   4  * even the most ancient of browsers, so be very careful when editing.
   5  */
   6 /*jshint unused: false, evil: true */
   7 /*globals mw, RLQ: true, NORLQ: true, $VARS, $CODE, performance */
   8
   9 var mediaWikiLoadStart = ( new Date() ).getTime(),
  10
  11         mwPerformance = ( window.performance && performance.mark ) ? performance : {
  12                 mark: function () {}
  13         };
  14
  15 mwPerformance.mark( 'mwLoadStart' );
  16
  17 /**
  18  * Returns false for Grade C supported browsers.
  19  *
  20  * This function should only be used by the Startup module, do not expand it to
  21  * be generally useful beyond startup.
  22  *
  23  * See also:
  24  * - https://www.mediawiki.org/wiki/Compatibility#Browsers
  25  * - https://jquery.com/browser-support/
  26  */
  27 function isCompatible( ua ) {
  28         if ( ua === undefined ) {
  29                 ua = navigator.userAgent;
  30         }
  31
  32         // Browsers with outdated or limited JavaScript engines get the no-JS experience
  33         return !(
  34                 // Internet Explorer < 9
  35                 ( ua.indexOf( 'MSIE' ) !== -1 && parseFloat( ua.split( 'MSIE' )[ 1 ] ) < 9 ) ||
  36                 // Firefox < 3
  37                 ( ua.indexOf( 'Firefox/' ) !== -1 && parseFloat( ua.split( 'Firefox/' )[ 1 ] ) < 3 ) ||
  38                 // Opera < 12
  39                 ( ua.indexOf( 'Opera/' ) !== -1 && ( ua.indexOf( 'Version/' ) === -1 ?
  40                         // "Opera/x.y"
  41                         parseFloat( ua.split( 'Opera/' )[ 1 ] ) < 10 :
  42                         // "Opera/9.80 ... Version/x.y"
  43                         parseFloat( ua.split( 'Version/' )[ 1 ] ) < 12
  44                 ) ) ||
  45                 // "Mozilla/0.0 ... Opera x.y"
  46                 ( ua.indexOf( 'Opera ' ) !== -1 && parseFloat( ua.split( ' Opera ' )[ 1 ] ) < 10 ) ||
  47                 // BlackBerry < 6
  48                 ua.match( /BlackBerry[^\/]*\/[1-5]\./ ) ||
  49                 // Open WebOS < 1.5
  50                 ua.match( /webOS\/1\.[0-4]/ ) ||
  51                 // Anything PlayStation based.
  52                 ua.match( /PlayStation/i ) ||
  53                 // Any Symbian based browsers
  54                 ua.match( /SymbianOS|Series60/ ) ||
  55                 // Any NetFront based browser
  56                 ua.match( /NetFront/ ) ||
  57                 // Opera Mini, all versions
  58                 ua.match( /Opera Mini/ ) ||
  59                 // Nokia's Ovi Browser
  60                 ua.match( /S40OviBrowser/ ) ||
  61                 // MeeGo's browser
  62                 ua.match( /MeeGo/ ) ||
  63                 // Google Glass browser groks JS but UI is too limited
  64                 ( ua.match( /Glass/ ) && ua.match( /Android/ ) )
  65         );
  66 }
  67
  68 // Conditional script injection
  69 ( function () {
  70         var NORLQ, script;
  71         if ( !isCompatible() ) {
  72                 // Undo class swapping in case of an unsupported browser.
  73                 // See OutputPage::getHeadScripts().
  74                 document.documentElement.className = document.documentElement.className
  75                         .replace( /(^|\s)client-js(\s|$)/, '$1client-nojs$2' );
  76
  77                 NORLQ = window.NORLQ || [];
  78                 while ( NORLQ.length ) {
  79                         NORLQ.shift()();
  80                 }
  81                 window.NORLQ = {
  82                         push: function ( fn ) {
  83                                 fn();
  84                         }
  85                 };
  86
  87                 // Clear and disable the other queue
  88                 window.RLQ = {
  89                         // No-op
  90                         push: function () {}
  91                 };
  92
  93                 return;
  94         }
  95
  96         /**
  97          * The $CODE and $VARS placeholders are substituted in ResourceLoaderStartUpModule.php.
  98          */
  99         function startUp() {
 100                 mw.config = new mw.Map( $VARS.wgLegacyJavaScriptGlobals );
 101
 102                 $CODE.registrations();
 103
 104                 mw.config.set( $VARS.configuration );
 105
 106                 // Must be after mw.config.set because these callbacks may use mw.loader which
 107                 // needs to have values 'skin', 'debug' etc. from mw.config.
 108                 var RLQ = window.RLQ || [];
 109                 while ( RLQ.length ) {
 110                         RLQ.shift()();
 111                 }
 112                 window.RLQ = {
 113                         push: function ( fn ) {
 114                                 fn();
 115                         }
 116                 };
 117
 118                 // Clear and disable the other queue
 119                 window.NORLQ = {
 120                         // No-op
 121                         push: function () {}
 122                 };
 123         }
 124
 125         script = document.createElement( 'script' );
 126         script.src = $VARS.baseModulesUri;
 127         script.onload = script.onreadystatechange = function () {
 128                 if ( !script.readyState || /loaded|complete/.test( script.readyState ) ) {
 129                         // Clean up
 130                         script.onload = script.onreadystatechange = null;
 131                         script = null;
 132                         // Callback
 133                         startUp();
 134                 }
 135         };
 136         document.getElementsByTagName( 'head' )[ 0 ].appendChild( script );
 137 }() );