Source: main/webapp/modules/BlobReader.js

  1. /*
  2.  * Licensed to the Apache Software Foundation (ASF) under one
  3.  * or more contributor license agreements.  See the NOTICE file
  4.  * distributed with this work for additional information
  5.  * regarding copyright ownership.  The ASF licenses this file
  6.  * to you under the Apache License, Version 2.0 (the
  7.  * "License"); you may not use this file except in compliance
  8.  * with the License.  You may obtain a copy of the License at
  9.  *
  10.  *   http://www.apache.org/licenses/LICENSE-2.0
  11.  *
  12.  * Unless required by applicable law or agreed to in writing,
  13.  * software distributed under the License is distributed on an
  14.  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  15.  * KIND, either express or implied.  See the License for the
  16.  * specific language governing permissions and limitations
  17.  * under the License.
  18.  */
  20. var Guacamole = Guacamole || {};
  22. /**
  23.  * A reader which automatically handles the given input stream, assembling all
  24.  * received blobs into a single blob by appending them to each other in order.
  25.  * Note that this object will overwrite any installed event handlers on the
  26.  * given Guacamole.InputStream.
  27.  * 
  28.  * @constructor
  29.  * @param {!Guacamole.InputStream} stream
  30.  *     The stream that data will be read from.
  31.  *
  32.  * @param {!string} mimetype
  33.  *     The mimetype of the blob being built.
  34.  */
  35. Guacamole.BlobReader = function(stream, mimetype) {
  37.     /**
  38.      * Reference to this Guacamole.InputStream.
  39.      *
  40.      * @private
  41.      * @type {!Guacamole.BlobReader}
  42.      */
  43.     var guac_reader = this;
  45.     /**
  46.      * The length of this Guacamole.InputStream in bytes.
  47.      *
  48.      * @private
  49.      * @type {!number}
  50.      */
  51.     var length = 0;
  53.     // Get blob builder
  54.     var blob_builder;
  55.     if      (window.BlobBuilder)       blob_builder = new BlobBuilder();
  56.     else if (window.WebKitBlobBuilder) blob_builder = new WebKitBlobBuilder();
  57.     else if (window.MozBlobBuilder)    blob_builder = new MozBlobBuilder();
  58.     else
  59.         blob_builder = new (function() {
  61.             var blobs = [];
  63.             /** @ignore */
  64.             this.append = function(data) {
  65.                 blobs.push(new Blob([data], {"type": mimetype}));
  66.             };
  68.             /** @ignore */
  69.             this.getBlob = function() {
  70.                 return new Blob(blobs, {"type": mimetype});
  71.             };
  73.         })();
  75.     // Append received blobs
  76.     stream.onblob = function(data) {
  78.         // Convert to ArrayBuffer
  79.         var binary = window.atob(data);
  80.         var arrayBuffer = new ArrayBuffer(binary.length);
  81.         var bufferView = new Uint8Array(arrayBuffer);
  83.         for (var i=0; i<binary.length; i++)
  84.             bufferView[i] = binary.charCodeAt(i);
  86.         blob_builder.append(arrayBuffer);
  87.         length += arrayBuffer.byteLength;
  89.         // Call handler, if present
  90.         if (guac_reader.onprogress)
  91.             guac_reader.onprogress(arrayBuffer.byteLength);
  93.         // Send success response
  94.         stream.sendAck("OK", 0x0000);
  96.     };
  98.     // Simply call onend when end received
  99.     stream.onend = function() {
  100.         if (guac_reader.onend)
  101.             guac_reader.onend();
  102.     };
  104.     /**
  105.      * Returns the current length of this Guacamole.InputStream, in bytes.
  106.      *
  107.      * @return {!number}
  108.      *     The current length of this Guacamole.InputStream.
  109.      */
  110.     this.getLength = function() {
  111.         return length;
  112.     };
  114.     /**
  115.      * Returns the contents of this Guacamole.BlobReader as a Blob.
  116.      *
  117.      * @return {!Blob}
  118.      *     The contents of this Guacamole.BlobReader.
  119.      */
  120.     this.getBlob = function() {
  121.         return blob_builder.getBlob();
  122.     };
  124.     /**
  125.      * Fired once for every blob of data received.
  126.      * 
  127.      * @event
  128.      * @param {!number} length
  129.      *     The number of bytes received.
  130.      */
  131.     this.onprogress = null;
  133.     /**
  134.      * Fired once this stream is finished and no further data will be written.
  135.      * @event
  136.      */
  137.     this.onend = null;
  139. };