Source: lib/polyfill/mediakeys.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.polyfill.MediaKeys');
  20. goog.require('shaka.log');
  21. goog.require('shaka.polyfill.PatchedMediaKeysMs');
  22. goog.require('shaka.polyfill.PatchedMediaKeysNop');
  23. goog.require('shaka.polyfill.PatchedMediaKeysWebkit');
  24. goog.require('shaka.polyfill.register');
  27. /**
  28.  * @namespace shaka.polyfill.MediaKeys
  29.  *
  30.  * @summary A polyfill to unify EME APIs across browser versions.
  31.  *
  32.  * The {@link https://w3c.github.io/encrypted-media/ EME spec} is still a
  33.  * work-in-progress.  As such, we need to provide a consistent API to the Shaka
  34.  * Player.  Until the spec is completely stable, the API provided by this
  35.  * polyfill may lag behind the latest spec developments.
  36.  */
  39. /**
  40.  * Install the polyfill if needed.
  41.  */
  42. shaka.polyfill.MediaKeys.install = function() {
  43.   shaka.log.debug('MediaKeys.install');
  45.   if (!window.HTMLVideoElement) {
  46.     // Avoid errors on very old browsers.
  47.     return;
  48.   }
  50.   if (navigator.requestMediaKeySystemAccess &&
  51.       MediaKeySystemAccess.prototype.getConfiguration) {
  52.     shaka.log.info('Using native EME as-is.');
  53.   } else if (HTMLMediaElement.prototype.webkitGenerateKeyRequest) {
  54.     shaka.log.info('Using webkit-prefixed EME v0.1b');
  55.     shaka.polyfill.PatchedMediaKeysWebkit.install('webkit');
  56.   } else if (HTMLMediaElement.prototype.generateKeyRequest) {
  57.     shaka.log.info('Using nonprefixed EME v0.1b');
  58.     shaka.polyfill.PatchedMediaKeysWebkit.install('');
  59.   } else if (window.MSMediaKeys) {
  60.     shaka.log.info('Using ms-prefixed EME v20140218');
  61.     shaka.polyfill.PatchedMediaKeysMs.install();
  62.   } else {
  63.     shaka.log.info('EME not available.');
  64.     shaka.polyfill.PatchedMediaKeysNop.install();
  65.   }
  66. };
  69. shaka.polyfill.register(shaka.polyfill.MediaKeys.install);