resources/src/mediawiki/api/upload.js

   1 /**
   2  * Provides an interface for uploading files to MediaWiki.
   3  *
   4  * @class mw.Api.plugin.upload
   5  * @singleton
   6  */
   7 ( function ( mw, $ ) {
   8         var nonce = 0,
   9                 fieldsAllowed = {
  10                         stash: true,
  11                         filekey: true,
  12                         filename: true,
  13                         comment: true,
  14                         text: true,
  15                         watchlist: true,
  16                         ignorewarnings: true
  17                 };
  18
  19         /**
  20          * Get nonce for iframe IDs on the page.
  21          *
  22          * @private
  23          * @return {number}
  24          */
  25         function getNonce() {
  26                 return nonce++;
  27         }
  28
  29         /**
  30          * Given a non-empty object, return one of its keys.
  31          *
  32          * @private
  33          * @param {Object} obj
  34          * @return {string}
  35          */
  36         function getFirstKey( obj ) {
  37                 var key;
  38                 for ( key in obj ) {
  39                         if ( obj.hasOwnProperty( key ) ) {
  40                                 return key;
  41                         }
  42                 }
  43         }
  44
  45         /**
  46          * Get new iframe object for an upload.
  47          *
  48          * @private
  49          * @return {HTMLIframeElement}
  50          */
  51         function getNewIframe( id ) {
  52                 var frame = document.createElement( 'iframe' );
  53                 frame.id = id;
  54                 frame.name = id;
  55                 return frame;
  56         }
  57
  58         /**
  59          * Shortcut for getting hidden inputs
  60          *
  61          * @private
  62          * @return {jQuery}
  63          */
  64         function getHiddenInput( name, val ) {
  65                 return $( '<input>' ).attr( 'type', 'hidden' )
  66                         .attr( 'name', name )
  67                         .val( val );
  68         }
  69
  70         /**
  71          * Process the result of the form submission, returned to an iframe.
  72          * This is the iframe's onload event.
  73          *
  74          * @param {HTMLIframeElement} iframe Iframe to extract result from
  75          * @return {Object} Response from the server. The return value may or may
  76          *   not be an XMLDocument, this code was copied from elsewhere, so if you
  77          *   see an unexpected return type, please file a bug.
  78          */
  79         function processIframeResult( iframe ) {
  80                 var json,
  81                         doc = iframe.contentDocument || frames[ iframe.id ].document;
  82
  83                 if ( doc.XMLDocument ) {
  84                         // The response is a document property in IE
  85                         return doc.XMLDocument;
  86                 }
  87
  88                 if ( doc.body ) {
  89                         // Get the json string
  90                         // We're actually searching through an HTML doc here --
  91                         // according to mdale we need to do this
  92                         // because IE does not load JSON properly in an iframe
  93                         json = $( doc.body ).find( 'pre' ).text();
  94
  95                         return JSON.parse( json );
  96                 }
  97
  98                 // Response is a xml document
  99                 return doc;
 100         }
 101
 102         function formDataAvailable() {
 103                 return window.FormData !== undefined &&
 104                         window.File !== undefined &&
 105                         window.File.prototype.slice !== undefined;
 106         }
 107
 108         $.extend( mw.Api.prototype, {
 109                 /**
 110                  * Upload a file to MediaWiki.
 111                  *
 112                  * The file will be uploaded using AJAX and FormData, if the browser supports it, or via an
 113                  * iframe if it doesn't.
 114                  *
 115                  * Caveats of iframe upload:
 116                  * - The returned jQuery.Promise will not receive `progress` notifications during the upload
 117                  * - It is incompatible with uploads to a foreign wiki using mw.ForeignApi
 118                  * - You must pass a HTMLInputElement and not a File for it to be possible
 119                  *
 120                  * @param {HTMLInputElement|File|Blob} file HTML input type=file element with a file already inside
 121                  *  of it, or a File object.
 122                  * @param {Object} data Other upload options, see action=upload API docs for more
 123                  * @return {jQuery.Promise}
 124                  */
 125                 upload: function ( file, data ) {
 126                         var isFileInput, canUseFormData;
 127
 128                         isFileInput = file && file.nodeType === Node.ELEMENT_NODE;
 129
 130                         if ( formDataAvailable() && isFileInput && file.files ) {
 131                                 file = file.files[ 0 ];
 132                         }
 133
 134                         if ( !file ) {
 135                                 throw new Error( 'No file' );
 136                         }
 137
 138                         // Blobs are allowed in formdata uploads, it turns out
 139                         canUseFormData = formDataAvailable() && ( file instanceof window.File || file instanceof window.Blob );
 140
 141                         if ( !isFileInput && !canUseFormData ) {
 142                                 throw new Error( 'Unsupported argument type passed to mw.Api.upload' );
 143                         }
 144
 145                         if ( canUseFormData ) {
 146                                 return this.uploadWithFormData( file, data );
 147                         }
 148
 149                         return this.uploadWithIframe( file, data );
 150                 },
 151
 152                 /**
 153                  * Upload a file to MediaWiki with an iframe and a form.
 154                  *
 155                  * This method is necessary for browsers without the File/FormData
 156                  * APIs, and continues to work in browsers with those APIs.
 157                  *
 158                  * The rough sketch of how this method works is as follows:
 159                  * 1. An iframe is loaded with no content.
 160                  * 2. A form is submitted with the passed-in file input and some extras.
 161                  * 3. The MediaWiki API receives that form data, and sends back a response.
 162                  * 4. The response is sent to the iframe, because we set target=(iframe id)
 163                  * 5. The response is parsed out of the iframe's document, and passed back
 164                  *    through the promise.
 165                  *
 166                  * @private
 167                  * @param {HTMLInputElement} file The file input with a file in it.
 168                  * @param {Object} data Other upload options, see action=upload API docs for more
 169                  * @return {jQuery.Promise}
 170                  */
 171                 uploadWithIframe: function ( file, data ) {
 172                         var key,
 173                                 tokenPromise = $.Deferred(),
 174                                 api = this,
 175                                 deferred = $.Deferred(),
 176                                 nonce = getNonce(),
 177                                 id = 'uploadframe-' + nonce,
 178                                 $form = $( '<form>' ),
 179                                 iframe = getNewIframe( id ),
 180                                 $iframe = $( iframe );
 181
 182                         for ( key in data ) {
 183                                 if ( !fieldsAllowed[ key ] ) {
 184                                         delete data[ key ];
 185                                 }
 186                         }
 187
 188                         data = $.extend( {}, this.defaults.parameters, { action: 'upload' }, data );
 189                         $form.addClass( 'mw-api-upload-form' );
 190
 191                         $form.css( 'display', 'none' )
 192                                 .attr( {
 193                                         action: this.defaults.ajax.url,
 194                                         method: 'POST',
 195                                         target: id,
 196                                         enctype: 'multipart/form-data'
 197                                 } );
 198
 199                         $iframe.one( 'load', function () {
 200                                 $iframe.one( 'load', function () {
 201                                         var result = processIframeResult( iframe );
 202                                         deferred.notify( 1 );
 203
 204                                         if ( !result ) {
 205                                                 deferred.reject( 'ok-but-empty', 'No response from API on upload attempt.' );
 206                                         } else if ( result.error ) {
 207                                                 if ( result.error.code === 'badtoken' ) {
 208                                                         api.badToken( 'csrf' );
 209                                                 }
 210
 211                                                 deferred.reject( result.error.code, result );
 212                                         } else if ( result.upload && result.upload.warnings ) {
 213                                                 deferred.reject( getFirstKey( result.upload.warnings ), result );
 214                                         } else {
 215                                                 deferred.resolve( result );
 216                                         }
 217                                 } );
 218                                 tokenPromise.done( function () {
 219                                         $form.submit();
 220                                 } );
 221                         } );
 222
 223                         $iframe.on( 'error', function ( error ) {
 224                                 deferred.reject( 'http', error );
 225                         } );
 226
 227                         $iframe.prop( 'src', 'about:blank' ).hide();
 228
 229                         file.name = 'file';
 230
 231                         $.each( data, function ( key, val ) {
 232                                 $form.append( getHiddenInput( key, val ) );
 233                         } );
 234
 235                         if ( !data.filename && !data.stash ) {
 236                                 throw new Error( 'Filename not included in file data.' );
 237                         }
 238
 239                         if ( this.needToken() ) {
 240                                 this.getEditToken().then( function ( token ) {
 241                                         $form.append( getHiddenInput( 'token', token ) );
 242                                         tokenPromise.resolve();
 243                                 }, tokenPromise.reject );
 244                         } else {
 245                                 tokenPromise.resolve();
 246                         }
 247
 248                         $( 'body' ).append( $form, $iframe );
 249
 250                         deferred.always( function () {
 251                                 $form.remove();
 252                                 $iframe.remove();
 253                         } );
 254
 255                         return deferred.promise();
 256                 },
 257
 258                 /**
 259                  * Uploads a file using the FormData API.
 260                  *
 261                  * @private
 262                  * @param {File} file
 263                  * @param {Object} data Other upload options, see action=upload API docs for more
 264                  * @return {jQuery.Promise}
 265                  */
 266                 uploadWithFormData: function ( file, data ) {
 267                         var key,
 268                                 deferred = $.Deferred();
 269
 270                         for ( key in data ) {
 271                                 if ( !fieldsAllowed[ key ] ) {
 272                                         delete data[ key ];
 273                                 }
 274                         }
 275
 276                         data = $.extend( {}, this.defaults.parameters, { action: 'upload' }, data );
 277                         data.file = file;
 278
 279                         if ( !data.filename && !data.stash ) {
 280                                 throw new Error( 'Filename not included in file data.' );
 281                         }
 282
 283                         // Use this.postWithEditToken() or this.post()
 284                         this[ this.needToken() ? 'postWithEditToken' : 'post' ]( data, {
 285                                 // Use FormData (if we got here, we know that it's available)
 286                                 contentType: 'multipart/form-data',
 287                                 // No timeout (default from mw.Api is 30 seconds)
 288                                 timeout: 0,
 289                                 // Provide upload progress notifications
 290                                 xhr: function () {
 291                                         var xhr = $.ajaxSettings.xhr();
 292                                         if ( xhr.upload ) {
 293                                                 // need to bind this event before we open the connection (see note at
 294                                                 // https://developer.mozilla.org/en-US/docs/DOM/XMLHttpRequest/Using_XMLHttpRequest#Monitoring_progress)
 295                                                 xhr.upload.addEventListener( 'progress', function ( ev ) {
 296                                                         if ( ev.lengthComputable ) {
 297                                                                 deferred.notify( ev.loaded / ev.total );
 298                                                         }
 299                                                 } );
 300                                         }
 301                                         return xhr;
 302                                 }
 303                         } )
 304                                 .done( function ( result ) {
 305                                         deferred.notify( 1 );
 306                                         if ( result.upload && result.upload.warnings ) {
 307                                                 deferred.reject( getFirstKey( result.upload.warnings ), result );
 308                                         } else {
 309                                                 deferred.resolve( result );
 310                                         }
 311                                 } )
 312                                 .fail( function ( errorCode, result ) {
 313                                         deferred.notify( 1 );
 314                                         deferred.reject( errorCode, result );
 315                                 } );
 316
 317                         return deferred.promise();
 318                 },
 319
 320                 /**
 321                  * Upload a file to the stash.
 322                  *
 323                  * This function will return a promise, which when resolved, will pass back a function
 324                  * to finish the stash upload. You can call that function with an argument containing
 325                  * more, or conflicting, data to pass to the server. For example:
 326                  *
 327                  *     // upload a file to the stash with a placeholder filename
 328                  *     api.uploadToStash( file, { filename: 'testing.png' } ).done( function ( finish ) {
 329                  *         // finish is now the function we can use to finalize the upload
 330                  *         // pass it a new filename from user input to override the initial value
 331                  *         finish( { filename: getFilenameFromUser() } ).done( function ( data ) {
 332                  *             // the upload is complete, data holds the API response
 333                  *         } );
 334                  *     } );
 335                  *
 336                  * @param {File|HTMLInputElement} file
 337                  * @param {Object} [data]
 338                  * @return {jQuery.Promise}
 339                  * @return {Function} return.finishStashUpload Call this function to finish the upload.
 340                  * @return {Object} return.finishStashUpload.data Additional data for the upload.
 341                  * @return {jQuery.Promise} return.finishStashUpload.return API promise for the final upload
 342                  * @return {Object} return.finishStashUpload.return.data API return value for the final upload
 343                  */
 344                 uploadToStash: function ( file, data ) {
 345                         var filekey,
 346                                 api = this;
 347
 348                         if ( !data.filename ) {
 349                                 throw new Error( 'Filename not included in file data.' );
 350                         }
 351
 352                         function finishUpload( moreData ) {
 353                                 return api.uploadFromStash( filekey, $.extend( data, moreData ) );
 354                         }
 355
 356                         return this.upload( file, { stash: true, filename: data.filename } ).then(
 357                                 function ( result ) {
 358                                         filekey = result.upload.filekey;
 359                                         return finishUpload;
 360                                 },
 361                                 function ( errorCode, result ) {
 362                                         if ( result && result.upload && result.upload.filekey ) {
 363                                                 // Ignore any warnings if 'filekey' was returned, that's all we care about
 364                                                 filekey = result.upload.filekey;
 365                                                 return $.Deferred().resolve( finishUpload );
 366                                         }
 367                                         return $.Deferred().reject( errorCode, result );
 368                                 }
 369                         );
 370                 },
 371
 372                 /**
 373                  * Finish an upload in the stash.
 374                  *
 375                  * @param {string} filekey
 376                  * @param {Object} data
 377                  */
 378                 uploadFromStash: function ( filekey, data ) {
 379                         data.filekey = filekey;
 380                         data.action = 'upload';
 381                         data.format = 'json';
 382
 383                         if ( !data.filename ) {
 384                                 throw new Error( 'Filename not included in file data.' );
 385                         }
 386
 387                         return this.postWithEditToken( data ).then( function ( result ) {
 388                                 if ( result.upload && result.upload.warnings ) {
 389                                         return $.Deferred().reject( getFirstKey( result.upload.warnings ), result ).promise();
 390                                 }
 391                                 return result;
 392                         } );
 393                 },
 394
 395                 needToken: function () {
 396                         return true;
 397                 }
 398         } );
 399
 400         /**
 401          * @class mw.Api
 402          * @mixins mw.Api.plugin.upload
 403          */
 404 }( mediaWiki, jQuery ) );