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