Source: lib/offline/offline_scheme.js

  1. /*! @license
  2.  * Shaka Player
  3.  * Copyright 2016 Google LLC
  4.  * SPDX-License-Identifier: Apache-2.0
  5.  */
  7. goog.provide('shaka.offline.OfflineScheme');
  9. goog.require('goog.asserts');
  10. goog.require('shaka.net.NetworkingEngine');
  11. goog.require('shaka.offline.OfflineUri');
  12. goog.require('shaka.offline.StorageMuxer');
  13. goog.require('shaka.util.AbortableOperation');
  14. goog.require('shaka.util.Error');
  17. /**
  18.  * @summary A plugin that handles requests for offline content.
  19.  * @export
  20.  */
  21. shaka.offline.OfflineScheme = class {
  22.   /**
  23.    * @param {string} uri
  24.    * @param {shaka.extern.Request} request
  25.    * @param {shaka.net.NetworkingEngine.RequestType} requestType
  26.    * @param {shaka.extern.ProgressUpdated} progressUpdated Called when a
  27.    *   progress event happened.
  28.    * @return {!shaka.extern.IAbortableOperation.<shaka.extern.Response>}
  29.    * @export
  30.    */
  31.   static plugin(uri, request, requestType, progressUpdated) {
  32.     const offlineUri = shaka.offline.OfflineUri.parse(uri);
  34.     if (offlineUri && offlineUri.isManifest()) {
  35.       return shaka.offline.OfflineScheme.getManifest_(uri);
  36.     }
  38.     if (offlineUri && offlineUri.isSegment()) {
  39.       return shaka.offline.OfflineScheme.getSegment_(
  40.           offlineUri.key(), offlineUri);
  41.     }
  43.     return shaka.util.AbortableOperation.failed(
  44.         new shaka.util.Error(
  45.             shaka.util.Error.Severity.CRITICAL,
  46.             shaka.util.Error.Category.NETWORK,
  47.             shaka.util.Error.Code.MALFORMED_OFFLINE_URI,
  48.             uri));
  49.   }
  51.   /**
  52.    * @param {string} uri
  53.    * @return {!shaka.extern.IAbortableOperation.<shaka.extern.Response>}
  54.    * @private
  55.    */
  56.   static getManifest_(uri) {
  57.     /** @type {shaka.extern.Response} */
  58.     const response = {
  59.       uri: uri,
  60.       originalUri: uri,
  61.       data: new ArrayBuffer(0),
  62.       headers: {'content-type': 'application/x-offline-manifest'},
  63.     };
  65.     return shaka.util.AbortableOperation.completed(response);
  66.   }
  68.   /**
  69.    * @param {number} id
  70.    * @param {!shaka.offline.OfflineUri} uri
  71.    * @return {!shaka.extern.IAbortableOperation.<shaka.extern.Response>}
  72.    * @private
  73.    */
  74.   static getSegment_(id, uri) {
  75.     goog.asserts.assert(
  76.         uri.isSegment(),
  77.         'Only segment uri\'s should be given to getSegment');
  79.     /** @type {!shaka.offline.StorageMuxer} */
  80.     const muxer = new shaka.offline.StorageMuxer();
  82.     return shaka.util.AbortableOperation.completed(undefined)
  83.         .chain(() => muxer.init())
  84.         .chain(() => muxer.getCell(uri.mechanism(), uri.cell()))
  85.         .chain((cell) => cell.getSegments([uri.key()]))
  86.         .chain((segments) => {
  87.           const segment = segments[0];
  89.           return {
  90.             uri: uri,
  91.             data: segment.data,
  92.             headers: {},
  93.           };
  94.         })
  95.         .finally(() => muxer.destroy());
  96.   }
  97. };
  99. shaka.net.NetworkingEngine.registerScheme(
  100.     'offline', shaka.offline.OfflineScheme.plugin);