resources/src/mediawiki.messagePoster/mediawiki.messagePoster.factory.js

   1 /*global OO*/
   2 ( function ( mw, $ ) {
   3         /**
   4          * This is a factory for MessagePoster objects, which allows a pluggable to way to script leaving a
   5          * talk page message.
   6          *
   7          * @class mw.messagePoster.factory
   8          * @singleton
   9          */
  10         function MwMessagePosterFactory() {
  11                 this.api = new mw.Api();
  12                 this.contentModelToClass = {};
  13         }
  14
  15         OO.initClass( MwMessagePosterFactory );
  16
  17         // Note: This registration scheme is currently not compatible with LQT, since that doesn't
  18         // have its own content model, just islqttalkpage.  LQT pages will be passed to the wikitext
  19         // MessagePoster.
  20         /**
  21          * Registers a MessagePoster subclass for a given content model.
  22          *
  23          * @param {string} contentModel Content model of pages this MessagePoster can post to
  24          * @param {Function} messagePosterConstructor Constructor for MessagePoster
  25          */
  26         MwMessagePosterFactory.prototype.register = function ( contentModel, messagePosterConstructor ) {
  27                 if ( this.contentModelToClass[contentModel] !== undefined ) {
  28                         throw new Error( 'The content model \'' + contentModel + '\' is already registered.' );
  29                 }
  30
  31                 this.contentModelToClass[contentModel] = messagePosterConstructor;
  32         };
  33
  34         /**
  35          * Unregisters a given content model
  36          * This is exposed for testing and should not normally be needed.
  37          *
  38          * @param {string} contentModel Content model to unregister
  39          */
  40         MwMessagePosterFactory.prototype.unregister = function ( contentModel ) {
  41                 delete this.contentModelToClass[contentModel];
  42         };
  43
  44         /**
  45          * Creates a MessagePoster, given a title.  A promise for this is returned.
  46          * This works by determining the content model, then loading the corresponding
  47          * module (which will register the MessagePoster class), and finally constructing it.
  48          *
  49          * This does not require the message and should be called as soon as possible, so it does the
  50          * API and ResourceLoader requests in the background.
  51          *
  52          * @param {mw.Title} title Title that will be posted to
  53          * @return {jQuery.Promise} Promise for the MessagePoster
  54          * @return {Function} return.done Called if MessagePoster is retrieved
  55          * @return {mw.messagePoster.MessagePoster} return.done.poster MessagePoster
  56          * @return {Function} return.fail Called if MessagePoster could not be constructed
  57          * @return {string} return.fail.errorCode String error code
  58          */
  59         MwMessagePosterFactory.prototype.create = function ( title ) {
  60                 var pageId, page, contentModel, moduleName,
  61                         factory = this;
  62
  63                 return this.api.get( {
  64                         action: 'query',
  65                         prop: 'info',
  66                         indexpageids: 1,
  67                         titles: title.getPrefixedDb()
  68                 } ).then( function ( result ) {
  69                         if ( result.query.pageids.length > 0 ) {
  70                                 pageId = result.query.pageids[0];
  71                                 page = result.query.pages[pageId];
  72
  73                                 contentModel = page.contentmodel;
  74                                 moduleName = 'mediawiki.messagePoster.' + contentModel;
  75                                 return mw.loader.using( moduleName ).then( function () {
  76                                         return factory.createForContentModel(
  77                                                 contentModel,
  78                                                 title
  79                                         );
  80                                 }, function () {
  81                                         return $.Deferred().reject( 'failed-to-load-module', 'Failed to load the \'' + moduleName + '\' module' );
  82                                 } );
  83                         } else {
  84                                 return $.Deferred().reject( 'unexpected-response', 'Unexpected API response' );
  85                         }
  86                 }, function ( errorCode, details ) {
  87                         return $.Deferred().reject( 'content-model-query-failed', errorCode, details );
  88                 } ).promise();
  89         };
  90
  91         /**
  92          * Creates a MessagePoster instance, given a title and content model
  93          *
  94          * @private
  95          *
  96          * @param {string} contentModel Content model of title
  97          * @param {mw.Title} title Title being posted to
  98          * @return {mw.messagePoster.MessagePoster}
  99          *
 100          */
 101         MwMessagePosterFactory.prototype.createForContentModel = function ( contentModel, title ) {
 102                 return new this.contentModelToClass[contentModel]( title );
 103         };
 104
 105         mw.messagePoster = {
 106                 factory: new MwMessagePosterFactory()
 107         };
 108 }( mediaWiki, jQuery ) );