Source: lib/net/data_uri_plugin.js

  1. /**
  2.  * @license
  3.  * Copyright 2016 Google Inc.
  4.  *
  5.  * Licensed under the Apache License, Version 2.0 (the "License");
  6.  * you may not use this file except in compliance with the License.
  7.  * You may obtain a copy of the License at
  8.  *
  9.  *     http://www.apache.org/licenses/LICENSE-2.0
  10.  *
  11.  * Unless required by applicable law or agreed to in writing, software
  12.  * distributed under the License is distributed on an "AS IS" BASIS,
  13.  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14.  * See the License for the specific language governing permissions and
  15.  * limitations under the License.
  16.  */
  18. goog.provide('shaka.net.DataUriPlugin');
  20. goog.require('shaka.log');
  21. goog.require('shaka.net.NetworkingEngine');
  22. goog.require('shaka.util.AbortableOperation');
  23. goog.require('shaka.util.Error');
  24. goog.require('shaka.util.StringUtils');
  25. goog.require('shaka.util.Uint8ArrayUtils');
  28. /**
  29.  * @namespace
  30.  * @summary A networking plugin to handle data URIs.
  31.  * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/data_URIs
  32.  * @param {string} uri
  33.  * @param {shakaExtern.Request} request
  34.  * @param {shaka.net.NetworkingEngine.RequestType=} requestType
  35.  * @return {!shakaExtern.IAbortableOperation.<shakaExtern.Response>}
  36.  * @export
  37.  */
  38. shaka.net.DataUriPlugin = function(uri, request, requestType) {
  39.   try {
  40.     let parsed = shaka.net.DataUriPlugin.parse(uri);
  42.     /** @type {shakaExtern.Response} */
  43.     let response = {
  44.       uri: uri,
  45.       data: parsed.data,
  46.       headers: {
  47.         'content-type': parsed.contentType
  48.       }
  49.     };
  51.     return shaka.util.AbortableOperation.completed(response);
  52.   } catch (error) {
  53.     return shaka.util.AbortableOperation.failed(error);
  54.   }
  55. };
  58. /**
  59.  * @param {string} uri
  60.  * @return {{data: ArrayBuffer, contentType: string}}
  61.  */
  62. shaka.net.DataUriPlugin.parse = function(uri) {
  63.   // Extract the scheme.
  64.   let parts = uri.split(':');
  65.   if (parts.length < 2 || parts[0] != 'data') {
  66.     shaka.log.error('Bad data URI, failed to parse scheme');
  67.     throw new shaka.util.Error(
  68.         shaka.util.Error.Severity.CRITICAL,
  69.         shaka.util.Error.Category.NETWORK,
  70.         shaka.util.Error.Code.MALFORMED_DATA_URI,
  71.         uri);
  72.   }
  73.   let path = parts.slice(1).join(':');
  75.   // Extract the encoding and MIME type (required but can be empty).
  76.   let infoAndData = path.split(',');
  77.   if (infoAndData.length < 2) {
  78.     shaka.log.error('Bad data URI, failed to extract encoding and MIME type');
  79.     throw new shaka.util.Error(
  80.         shaka.util.Error.Severity.CRITICAL,
  81.         shaka.util.Error.Category.NETWORK,
  82.         shaka.util.Error.Code.MALFORMED_DATA_URI,
  83.         uri);
  84.   }
  85.   let info = infoAndData[0];
  86.   let dataStr = window.decodeURIComponent(infoAndData.slice(1).join(','));
  88.   // Extract the encoding (optional).
  89.   let typeAndEncoding = info.split(';');
  90.   let encoding = null;
  91.   if (typeAndEncoding.length > 1) {
  92.     encoding = typeAndEncoding[1];
  93.   }
  95.   // Convert the data.
  96.   /** @type {ArrayBuffer} */
  97.   let data;
  98.   if (encoding == 'base64') {
  99.     data = shaka.util.Uint8ArrayUtils.fromBase64(dataStr).buffer;
  100.   } else if (encoding) {
  101.     shaka.log.error('Bad data URI, unknown encoding');
  102.     throw new shaka.util.Error(
  103.         shaka.util.Error.Severity.CRITICAL,
  104.         shaka.util.Error.Category.NETWORK,
  105.         shaka.util.Error.Code.UNKNOWN_DATA_URI_ENCODING,
  106.         uri);
  107.   } else {
  108.     data = shaka.util.StringUtils.toUTF8(dataStr);
  109.   }
  111.   return {data: data, contentType: typeAndEncoding[0]};
  112. };
  115. shaka.net.NetworkingEngine.registerScheme('data', shaka.net.DataUriPlugin);