/*! @license
* Shaka Player
* Copyright 2016 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
goog.provide('shaka.offline.Storage');
goog.require('goog.asserts');
goog.require('shaka.Player');
goog.require('shaka.log');
goog.require('shaka.media.DrmEngine');
goog.require('shaka.media.ManifestParser');
goog.require('shaka.net.NetworkingEngine');
goog.require('shaka.offline.DownloadInfo');
goog.require('shaka.offline.DownloadManager');
goog.require('shaka.offline.OfflineUri');
goog.require('shaka.offline.SessionDeleter');
goog.require('shaka.offline.StorageMuxer');
goog.require('shaka.offline.StoredContentUtils');
goog.require('shaka.offline.StreamBandwidthEstimator');
goog.require('shaka.util.AbortableOperation');
goog.require('shaka.util.ArrayUtils');
goog.require('shaka.util.ConfigUtils');
goog.require('shaka.util.Destroyer');
goog.require('shaka.util.Error');
goog.require('shaka.util.IDestroyable');
goog.require('shaka.util.Iterables');
goog.require('shaka.util.MimeUtils');
goog.require('shaka.util.Platform');
goog.require('shaka.util.PlayerConfiguration');
goog.require('shaka.util.StreamUtils');
goog.requireType('shaka.media.SegmentReference');
goog.requireType('shaka.offline.StorageCellHandle');
/**
* @summary
* This manages persistent offline data including storage, listing, and deleting
* stored manifests. Playback of offline manifests are done through the Player
* using a special URI (see shaka.offline.OfflineUri).
*
* First, check support() to see if offline is supported by the platform.
* Second, configure() the storage object with callbacks to your application.
* Third, call store(), remove(), or list() as needed.
* When done, call destroy().
*
* @implements {shaka.util.IDestroyable}
* @export
*/
shaka.offline.Storage = class {
/**
* @param {!shaka.Player=} player
* A player instance to share a networking engine and configuration with.
* When initializing with a player, storage is only valid as long as
* |destroy| has not been called on the player instance. When omitted,
* storage will manage its own networking engine and configuration.
*/
constructor(player) {
// It is an easy mistake to make to pass a Player proxy from CastProxy.
// Rather than throw a vague exception later, throw an explicit and clear
// one now.
//
// TODO(vaage): After we decide whether or not we want to support
// initializing storage with a player proxy, we should either remove
// this error or rename the error.
if (player && player.constructor != shaka.Player) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.STORAGE,
shaka.util.Error.Code.LOCAL_PLAYER_INSTANCE_REQUIRED);
}
/** @private {?shaka.extern.PlayerConfiguration} */
this.config_ = null;
/** @private {shaka.net.NetworkingEngine} */
this.networkingEngine_ = null;
// Initialize |config_| and |networkingEngine_| based on whether or not
// we were given a player instance.
if (player) {
this.config_ = player.getSharedConfiguration();
this.networkingEngine_ = player.getNetworkingEngine();
goog.asserts.assert(
this.networkingEngine_,
'Storage should not be initialized with a player that had ' +
'|destroy| called on it.');
} else {
this.config_ = shaka.util.PlayerConfiguration.createDefault();
this.networkingEngine_ = new shaka.net.NetworkingEngine();
}
/**
* A list of open operations that are being performed by this instance of
* |shaka.offline.Storage|.
*
* @private {!Array.<!Promise>}
*/
this.openOperations_ = [];
/**
* A list of open download managers that are being used to download things.
*
* @private {!Array.<!shaka.offline.DownloadManager>}
*/
this.openDownloadManagers_ = [];
/**
* Storage should only destroy the networking engine if it was initialized
* without a player instance. Store this as a flag here to avoid including
* the player object in the destoyer's closure.
*
* @type {boolean}
*/
const destroyNetworkingEngine = !player;
/** @private {!shaka.util.Destroyer} */
this.destroyer_ = new shaka.util.Destroyer(async () => {
// Cancel all in-progress store operations.
await Promise.all(this.openDownloadManagers_.map((dl) => dl.abortAll()));
// Wait for all remaining open operations to end. Wrap each operations so
// that a single rejected promise won't cause |Promise.all| to return
// early or to return a rejected Promise.
const noop = () => {};
const awaits = [];
for (const op of this.openOperations_) {
awaits.push(op.then(noop, noop));
}
await Promise.all(awaits);
// Wait until after all the operations have finished before we destroy
// the networking engine to avoid any unexpected errors.
if (destroyNetworkingEngine) {
await this.networkingEngine_.destroy();
}
// Drop all references to internal objects to help with GC.
this.config_ = null;
this.networkingEngine_ = null;
});
}
/**
* Gets whether offline storage is supported. Returns true if offline storage
* is supported for clear content. Support for offline storage of encrypted
* content will not be determined until storage is attempted.
*
* @return {boolean}
* @export
*/
static support() {
// Our Storage system is useless without MediaSource. MediaSource allows us
// to pull data from anywhere (including our Storage system) and feed it to
// the video element.
if (!shaka.util.Platform.supportsMediaSource()) {
return false;
}
return shaka.offline.StorageMuxer.support();
}
/**
* @override
* @export
*/
destroy() {
return this.destroyer_.destroy();
}
/**
* Sets configuration values for Storage. This is associated with
* Player.configure and will change the player instance given at
* initialization.
*
* @param {string|!Object} config This should either be a field name or an
* object following the form of {@link shaka.extern.PlayerConfiguration},
* where you may omit any field you do not wish to change.
* @param {*=} value This should be provided if the previous parameter
* was a string field name.
* @return {boolean}
* @export
*/
configure(config, value) {
goog.asserts.assert(typeof(config) == 'object' || arguments.length == 2,
'String configs should have values!');
// ('fieldName', value) format
if (arguments.length == 2 && typeof(config) == 'string') {
config = shaka.util.ConfigUtils.convertToConfigObject(config, value);
}
goog.asserts.assert(typeof(config) == 'object', 'Should be an object!');
goog.asserts.assert(
this.config_, 'Cannot reconfigure storage after calling destroy.');
return shaka.util.PlayerConfiguration.mergeConfigObjects(
/* destination= */ this.config_, /* updates= */ config );
}
/**
* Return a copy of the current configuration. Modifications of the returned
* value will not affect the Storage instance's active configuration. You
* must call storage.configure() to make changes.
*
* @return {shaka.extern.PlayerConfiguration}
* @export
*/
getConfiguration() {
goog.asserts.assert(this.config_, 'Config must not be null!');
const ret = shaka.util.PlayerConfiguration.createDefault();
shaka.util.PlayerConfiguration.mergeConfigObjects(
ret, this.config_, shaka.util.PlayerConfiguration.createDefault());
return ret;
}
/**
* Return the networking engine that storage is using. If storage was
* initialized with a player instance, then the networking engine returned
* will be the same as |player.getNetworkingEngine()|.
*
* The returned value will only be null if |destroy| was called before
* |getNetworkingEngine|.
*
* @return {shaka.net.NetworkingEngine}
* @export
*/
getNetworkingEngine() {
return this.networkingEngine_;
}
/**
* Stores the given manifest. If the content is encrypted, and encrypted
* content cannot be stored on this platform, the Promise will be rejected
* with error code 6001, REQUESTED_KEY_SYSTEM_CONFIG_UNAVAILABLE.
* Multiple assets can be downloaded at the same time, but note that since
* the storage instance has a single networking engine, multiple storage
* objects will be necessary if some assets require unique network filters.
* This snapshots the storage config at the time of the call, so it will not
* honor any changes to config mid-store operation.
*
* @param {string} uri The URI of the manifest to store.
* @param {!Object=} appMetadata An arbitrary object from the application
* that will be stored along-side the offline content. Use this for any
* application-specific metadata you need associated with the stored
* content. For details on the data types that can be stored here, please
* refer to {@link https://bit.ly/StructClone}
* @param {string=} mimeType
* The mime type for the content |manifestUri| points to.
* @return {!shaka.extern.IAbortableOperation.<shaka.extern.StoredContent>}
* An AbortableOperation that resolves with a structure representing what
* was stored. The "offlineUri" member is the URI that should be given to
* Player.load() to play this piece of content offline. The "appMetadata"
* member is the appMetadata argument you passed to store().
* If you want to cancel this download, call the "abort" method on
* AbortableOperation.
* @export
*/
store(uri, appMetadata, mimeType) {
goog.asserts.assert(
this.networkingEngine_,
'Cannot call |store| after calling |destroy|.');
// Get a copy of the current config.
const config = this.getConfiguration();
const getParser = async () => {
goog.asserts.assert(
this.networkingEngine_, 'Should not call |store| after |destroy|');
const factory = await shaka.media.ManifestParser.getFactory(
uri,
this.networkingEngine_,
config.manifest.retryParameters,
mimeType || null);
return factory();
};
/** @type {!shaka.offline.DownloadManager} */
const downloader =
new shaka.offline.DownloadManager(this.networkingEngine_);
this.openDownloadManagers_.push(downloader);
const storeOp = this.store_(
uri, appMetadata || {}, getParser, config, downloader);
const abortableStoreOp = new shaka.util.AbortableOperation(storeOp, () => {
return downloader.abortAll();
});
abortableStoreOp.finally(() => {
shaka.util.ArrayUtils.remove(this.openDownloadManagers_, downloader);
});
return this.startAbortableOperation_(abortableStoreOp);
}
/**
* See |shaka.offline.Storage.store| for details.
*
* @param {string} uri
* @param {!Object} appMetadata
* @param {function():!Promise.<shaka.extern.ManifestParser>} getParser
* @param {shaka.extern.PlayerConfiguration} config
* @param {!shaka.offline.DownloadManager} downloader
* @return {!Promise.<shaka.extern.StoredContent>}
* @private
*/
async store_(uri, appMetadata, getParser, config, downloader) {
this.requireSupport_();
// Since we will need to use |parser|, |drmEngine|, |activeHandle|, and
// |muxer| in the catch/finally blocks, we need to define them out here.
// Since they may not get initialized when we enter the catch/finally block,
// we need to assume that they may be null/undefined when we get there.
/** @type {?shaka.extern.ManifestParser} */
let parser = null;
/** @type {?shaka.media.DrmEngine} */
let drmEngine = null;
/** @type {shaka.offline.StorageMuxer} */
const muxer = new shaka.offline.StorageMuxer();
/** @type {?shaka.offline.StorageCellHandle} */
let activeHandle = null;
/** @type {?number} */
let manifestId = null;
// This will be used to store any errors from drm engine. Whenever drm
// engine is passed to another function to do work, we should check if this
// was set.
let drmError = null;
try {
parser = await getParser();
const manifest = await this.parseManifest(uri, parser, config);
// Check if we were asked to destroy ourselves while we were "away"
// downloading the manifest.
this.ensureNotDestroyed_();
// Check if we can even download this type of manifest before trying to
// create the drm engine.
const canDownload = !manifest.presentationTimeline.isLive() &&
!manifest.presentationTimeline.isInProgress();
if (!canDownload) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.STORAGE,
shaka.util.Error.Code.CANNOT_STORE_LIVE_OFFLINE,
uri);
}
// Create the DRM engine, and load the keys in the manifest.
drmEngine = await this.createDrmEngine(
manifest,
(e) => { drmError = drmError || e; },
config);
// We could have been asked to destroy ourselves while we were "away"
// creating the drm engine.
this.ensureNotDestroyed_();
if (drmError) {
throw drmError;
}
await this.filterManifest_(manifest, drmEngine, config);
await muxer.init();
this.ensureNotDestroyed_();
// Get the cell that we are saving the manifest to. Once we get a cell
// we will only reference the cell and not the muxer so that the manifest
// and segments will all be saved to the same cell.
activeHandle = await muxer.getActive();
this.ensureNotDestroyed_();
goog.asserts.assert(drmEngine, 'drmEngine should be non-null here.');
const {manifestDB, toDownload} = this.makeManifestDB_(
drmEngine, manifest, uri, appMetadata, config, downloader);
// Store the empty manifest, before downloading the segments.
const ids = await activeHandle.cell.addManifests([manifestDB]);
this.ensureNotDestroyed_();
manifestId = ids[0];
goog.asserts.assert(drmEngine, 'drmEngine should be non-null here.');
this.ensureNotDestroyed_();
if (drmError) {
throw drmError;
}
await this.downloadSegments_(toDownload, manifestId, manifestDB,
downloader, config, activeHandle.cell, manifest, drmEngine);
this.ensureNotDestroyed_();
const offlineUri = shaka.offline.OfflineUri.manifest(
activeHandle.path.mechanism, activeHandle.path.cell, manifestId);
return shaka.offline.StoredContentUtils.fromManifestDB(
offlineUri, manifestDB);
} catch (e) {
if (manifestId != null) {
await shaka.offline.Storage.cleanStoredManifest(manifestId);
}
// If we already had an error, ignore this error to avoid hiding
// the original error.
throw drmError || e;
} finally {
await muxer.destroy();
if (parser) {
await parser.stop();
}
if (drmEngine) {
await drmEngine.destroy();
}
}
}
/**
* Download and then store the contents of each segment.
* The promise this returns will wait for local downloads.
*
* @param {!Array.<!shaka.offline.DownloadInfo>} toDownload
* @param {number} manifestId
* @param {shaka.extern.ManifestDB} manifestDB
* @param {!shaka.offline.DownloadManager} downloader
* @param {shaka.extern.PlayerConfiguration} config
* @param {shaka.extern.StorageCell} storage
* @param {shaka.extern.Manifest} manifest
* @param {!shaka.media.DrmEngine} drmEngine
* @return {!Promise}
* @private
*/
async downloadSegments_(
toDownload, manifestId, manifestDB, downloader, config, storage,
manifest, drmEngine) {
let pendingManifestUpdates = {};
let pendingDataSize = 0;
/**
* @param {!Array.<!shaka.offline.DownloadInfo>} toDownload
* @param {boolean} updateDRM
*/
const download = async (toDownload, updateDRM) => {
for (const download of toDownload) {
const request = download.makeSegmentRequest(config);
const estimateId = download.estimateId;
const isInitSegment = download.isInitSegment;
const onDownloaded = async (data) => {
// Store the data.
const dataKeys = await storage.addSegments([{data}]);
this.ensureNotDestroyed_();
// Store the necessary update to the manifest, to be processed later.
const ref = /** @type {!shaka.media.SegmentReference} */ (
download.ref);
const id = shaka.offline.DownloadInfo.idForSegmentRef(ref);
pendingManifestUpdates[id] = dataKeys[0];
pendingDataSize += data.byteLength;
};
downloader.queue(download.groupId,
request, estimateId, isInitSegment, onDownloaded);
}
await downloader.waitToFinish();
if (updateDRM) {
// Re-store the manifest, to attach session IDs.
// These were (maybe) discovered inside the downloader; we can only add
// them now, at the end, since the manifestDB is in flux during the
// process of downloading and storing, and assignSegmentsToManifest
// does not know about the DRM engine.
this.ensureNotDestroyed_();
this.setManifestDrmFields_(manifest, manifestDB, drmEngine, config);
await storage.updateManifest(manifestId, manifestDB);
}
};
const usingBgFetch = false; // TODO: Get.
try {
if (this.getManifestIsEncrypted_(manifest) && usingBgFetch &&
!this.getManifestIncludesInitData_(manifest)) {
// Background fetch can't make DRM sessions, so if we have to get the
// init data from the init segments, download those first before
// anything else.
await download(toDownload.filter((info) => info.isInitSegment), true);
this.ensureNotDestroyed_();
toDownload = toDownload.filter((info) => !info.isInitSegment);
// Copy these and reset them now, before calling await.
const manifestUpdates = pendingManifestUpdates;
const dataSize = pendingDataSize;
pendingManifestUpdates = {};
pendingDataSize = 0;
await shaka.offline.Storage.assignSegmentsToManifest(
storage, manifestId, manifestDB, manifestUpdates, dataSize,
() => this.ensureNotDestroyed_());
this.ensureNotDestroyed_();
}
if (!usingBgFetch) {
await download(toDownload, false);
this.ensureNotDestroyed_();
// Copy these and reset them now, before calling await.
const manifestUpdates = pendingManifestUpdates;
const dataSize = pendingDataSize;
pendingManifestUpdates = {};
pendingDataSize = 0;
await shaka.offline.Storage.assignSegmentsToManifest(
storage, manifestId, manifestDB, manifestUpdates, dataSize,
() => this.ensureNotDestroyed_());
this.ensureNotDestroyed_();
goog.asserts.assert(
!manifestDB.isIncomplete, 'The manifest should be complete by now');
} else {
// TODO: Send the request to the service worker. Don't await the result.
}
} catch (error) {
const dataKeys = Object.values(pendingManifestUpdates);
// Remove these pending segments that are not yet linked to the manifest.
await storage.removeSegments(dataKeys, (key) => {});
throw error;
}
}
/**
* Removes all of the contents for a given manifest, statelessly.
*
* @param {number} manifestId
* @return {!Promise}
*/
static async cleanStoredManifest(manifestId) {
const muxer = new shaka.offline.StorageMuxer();
await muxer.init();
const activeHandle = await muxer.getActive();
const uri = shaka.offline.OfflineUri.manifest(
activeHandle.path.mechanism,
activeHandle.path.cell,
manifestId);
await muxer.destroy();
const storage = new shaka.offline.Storage();
await storage.remove(uri.toString());
}
/**
* Updates the given manifest, assigns database keys to segments, then stores
* the updated manifest.
*
* It is up to the caller to ensure that this method is not called
* concurrently on the same manifest.
*
* @param {shaka.extern.StorageCell} storage
* @param {number} manifestId
* @param {!shaka.extern.ManifestDB} manifestDB
* @param {!Object.<string, number>} manifestUpdates
* @param {number} dataSizeUpdate
* @param {function()} throwIfAbortedFn A function that should throw if the
* download has been aborted.
* @return {!Promise}
*/
static async assignSegmentsToManifest(
storage, manifestId, manifestDB, manifestUpdates, dataSizeUpdate,
throwIfAbortedFn) {
let manifestUpdated = false;
try {
// Assign the stored data to the manifest.
let complete = true;
for (const stream of manifestDB.streams) {
for (const segment of stream.segments) {
let dataKey = segment.pendingSegmentRefId ?
manifestUpdates[segment.pendingSegmentRefId] : null;
if (dataKey != null) {
segment.dataKey = dataKey;
// Now that the segment has been associated with the appropriate
// dataKey, the pendingSegmentRefId is no longer necessary.
segment.pendingSegmentRefId = undefined;
}
dataKey = segment.pendingInitSegmentRefId ?
manifestUpdates[segment.pendingInitSegmentRefId] : null;
if (dataKey != null) {
segment.initSegmentKey = dataKey;
// Now that the init segment has been associated with the
// appropriate initSegmentKey, the pendingInitSegmentRefId is no
// longer necessary.
segment.pendingInitSegmentRefId = undefined;
}
if (segment.pendingSegmentRefId) {
complete = false;
}
if (segment.pendingInitSegmentRefId) {
complete = false;
}
}
}
// Update the size of the manifest.
manifestDB.size += dataSizeUpdate;
// Mark the manifest as complete, if all segments are downloaded.
if (complete) {
manifestDB.isIncomplete = false;
}
// Update the manifest.
await storage.updateManifest(manifestId, manifestDB);
manifestUpdated = true;
throwIfAbortedFn();
} catch (e) {
await shaka.offline.Storage.cleanStoredManifest(manifestId);
if (!manifestUpdated) {
const dataKeys = Object.values(manifestUpdates);
// The cleanStoredManifest method will not "see" any segments that have
// been downloaded but not assigned to the manifest yet. So un-store
// them separately.
await storage.removeSegments(dataKeys, (key) => {});
}
throw e;
}
}
/**
* Filter |manifest| such that it will only contain the variants and text
* streams that we want to store and can actually play.
*
* @param {shaka.extern.Manifest} manifest
* @param {!shaka.media.DrmEngine} drmEngine
* @param {shaka.extern.PlayerConfiguration} config
* @return {!Promise}
* @private
*/
async filterManifest_(manifest, drmEngine, config) {
// Filter the manifest based on the restrictions given in the player
// configuration.
const maxHwRes = {width: Infinity, height: Infinity};
shaka.util.StreamUtils.filterByRestrictions(
manifest, config.restrictions, maxHwRes);
// Filter the manifest based on what we know MediaCapabilities will be able
// to play later (no point storing something we can't play).
await shaka.util.StreamUtils.filterManifestByMediaCapabilities(
manifest, config.offline.usePersistentLicense);
// Gather all tracks.
const allTracks = [];
// Choose the codec that has the lowest average bandwidth.
const preferredAudioChannelCount = config.preferredAudioChannelCount;
const preferredDecodingAttributes = config.preferredDecodingAttributes;
const preferredVideoCodecs = config.preferredVideoCodecs;
const preferredAudioCodecs = config.preferredAudioCodecs;
shaka.util.StreamUtils.chooseCodecsAndFilterManifest(
manifest, preferredVideoCodecs, preferredAudioCodecs,
preferredAudioChannelCount, preferredDecodingAttributes);
for (const variant of manifest.variants) {
goog.asserts.assert(
shaka.util.StreamUtils.isPlayable(variant),
'We should have already filtered by "is playable"');
allTracks.push(shaka.util.StreamUtils.variantToTrack(variant));
}
for (const text of manifest.textStreams) {
allTracks.push(shaka.util.StreamUtils.textStreamToTrack(text));
}
for (const image of manifest.imageStreams) {
allTracks.push(shaka.util.StreamUtils.imageStreamToTrack(image));
}
// Let the application choose which tracks to store.
const chosenTracks =
await config.offline.trackSelectionCallback(allTracks);
const duration = manifest.presentationTimeline.getDuration();
let sizeEstimate = 0;
for (const track of chosenTracks) {
const trackSize = track.bandwidth * duration / 8;
sizeEstimate += trackSize;
}
try {
const allowedDownload =
await config.offline.downloadSizeCallback(sizeEstimate);
if (!allowedDownload) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.STORAGE,
shaka.util.Error.Code.STORAGE_LIMIT_REACHED);
}
} catch (e) {
// It is necessary to be able to catch the STORAGE_LIMIT_REACHED error
if (e instanceof shaka.util.Error) {
throw e;
}
shaka.log.warning(
'downloadSizeCallback has produced an unexpected error', e);
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.STORAGE,
shaka.util.Error.Code.DOWNLOAD_SIZE_CALLBACK_ERROR);
}
/** @type {!Set.<number>} */
const variantIds = new Set();
/** @type {!Set.<number>} */
const textIds = new Set();
/** @type {!Set.<number>} */
const imageIds = new Set();
// Collect the IDs of the chosen tracks.
for (const track of chosenTracks) {
if (track.type == 'variant') {
variantIds.add(track.id);
}
if (track.type == 'text') {
textIds.add(track.id);
}
if (track.type == 'image') {
imageIds.add(track.id);
}
}
// Filter the manifest to keep only what the app chose.
manifest.variants =
manifest.variants.filter((variant) => variantIds.has(variant.id));
manifest.textStreams =
manifest.textStreams.filter((stream) => textIds.has(stream.id));
manifest.imageStreams =
manifest.imageStreams.filter((stream) => imageIds.has(stream.id));
// Check the post-filtered manifest for characteristics that may indicate
// issues with how the app selected tracks.
shaka.offline.Storage.validateManifest_(manifest);
}
/**
* Create a download manager and download the manifest.
* This also sets up download infos for each segment to be downloaded.
*
* @param {!shaka.media.DrmEngine} drmEngine
* @param {shaka.extern.Manifest} manifest
* @param {string} uri
* @param {!Object} metadata
* @param {shaka.extern.PlayerConfiguration} config
* @param {!shaka.offline.DownloadManager} downloader
* @return {{
* manifestDB: shaka.extern.ManifestDB,
* toDownload: !Array.<!shaka.offline.DownloadInfo>
* }}
* @private
*/
makeManifestDB_(drmEngine, manifest, uri, metadata, config, downloader) {
const pendingContent = shaka.offline.StoredContentUtils.fromManifest(
uri, manifest, /* size= */ 0, metadata);
// In https://github.com/shaka-project/shaka-player/issues/2652, we found
// that this callback would be removed by the compiler if we reference the
// config in the onProgress closure below. Reading it into a local
// variable first seems to work around this apparent compiler bug.
const progressCallback = config.offline.progressCallback;
const onProgress = (progress, size) => {
// Update the size of the stored content before issuing a progress
// update.
pendingContent.size = size;
progressCallback(pendingContent, progress);
};
const onInitData = (initData, systemId) => {
if (needsInitData && config.offline.usePersistentLicense &&
currentSystemId == systemId) {
drmEngine.newInitData('cenc', initData);
}
};
downloader.setCallbacks(onProgress, onInitData);
const needsInitData = this.getManifestIsEncrypted_(manifest) &&
!this.getManifestIncludesInitData_(manifest);
let currentSystemId = null;
if (needsInitData) {
const drmInfo = drmEngine.getDrmInfo();
currentSystemId =
shaka.offline.Storage.defaultSystemIds_.get(drmInfo.keySystem);
}
// Make the estimator, which is used to make the download registries.
const estimator = new shaka.offline.StreamBandwidthEstimator();
for (const stream of manifest.textStreams) {
estimator.addText(stream);
}
for (const stream of manifest.imageStreams) {
estimator.addImage(stream);
}
for (const variant of manifest.variants) {
estimator.addVariant(variant);
}
const {streams, toDownload} = this.createStreams_(
downloader, estimator, drmEngine, manifest, config);
const drmInfo = drmEngine.getDrmInfo();
const usePersistentLicense = config.offline.usePersistentLicense;
if (drmInfo && usePersistentLicense) {
// Don't store init data, since we have stored sessions.
drmInfo.initData = [];
}
const manifestDB = {
creationTime: Date.now(),
originalManifestUri: uri,
duration: manifest.presentationTimeline.getDuration(),
size: 0,
expiration: drmEngine.getExpiration(),
streams,
sessionIds: usePersistentLicense ? drmEngine.getSessionIds() : [],
drmInfo,
appMetadata: metadata,
isIncomplete: true,
sequenceMode: manifest.sequenceMode,
};
return {manifestDB, toDownload};
}
/**
* @param {shaka.extern.Manifest} manifest
* @return {boolean}
* @private
*/
getManifestIsEncrypted_(manifest) {
return manifest.variants.some((variant) => {
const videoEncrypted = variant.video && variant.video.encrypted;
const audioEncrypted = variant.audio && variant.audio.encrypted;
return videoEncrypted || audioEncrypted;
});
}
/**
* @param {shaka.extern.Manifest} manifest
* @return {boolean}
* @private
*/
getManifestIncludesInitData_(manifest) {
return manifest.variants.some((variant) => {
const videoDrmInfos = variant.video ? variant.video.drmInfos : [];
const audioDrmInfos = variant.audio ? variant.audio.drmInfos : [];
const drmInfos = videoDrmInfos.concat(audioDrmInfos);
return drmInfos.some((drmInfos) => {
return drmInfos.initData && drmInfos.initData.length;
});
});
}
/**
* @param {shaka.extern.Manifest} manifest
* @param {shaka.extern.ManifestDB} manifestDB
* @param {!shaka.media.DrmEngine} drmEngine
* @param {shaka.extern.PlayerConfiguration} config
* @private
*/
setManifestDrmFields_(manifest, manifestDB, drmEngine, config) {
manifestDB.expiration = drmEngine.getExpiration();
const sessions = drmEngine.getSessionIds();
manifestDB.sessionIds = config.offline.usePersistentLicense ?
sessions : [];
if (this.getManifestIsEncrypted_(manifest) &&
config.offline.usePersistentLicense && !sessions.length) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.STORAGE,
shaka.util.Error.Code.NO_INIT_DATA_FOR_OFFLINE);
}
}
/**
* Removes the given stored content. This will also attempt to release the
* licenses, if any.
*
* @param {string} contentUri
* @return {!Promise}
* @export
*/
remove(contentUri) {
return this.startOperation_(this.remove_(contentUri));
}
/**
* See |shaka.offline.Storage.remove| for details.
*
* @param {string} contentUri
* @return {!Promise}
* @private
*/
async remove_(contentUri) {
this.requireSupport_();
const nullableUri = shaka.offline.OfflineUri.parse(contentUri);
if (nullableUri == null || !nullableUri.isManifest()) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.STORAGE,
shaka.util.Error.Code.MALFORMED_OFFLINE_URI,
contentUri);
}
/** @type {!shaka.offline.OfflineUri} */
const uri = nullableUri;
/** @type {!shaka.offline.StorageMuxer} */
const muxer = new shaka.offline.StorageMuxer();
try {
await muxer.init();
const cell = await muxer.getCell(uri.mechanism(), uri.cell());
const manifests = await cell.getManifests([uri.key()]);
const manifest = manifests[0];
await Promise.all([
this.removeFromDRM_(uri, manifest, muxer),
this.removeFromStorage_(cell, uri, manifest),
]);
} finally {
await muxer.destroy();
}
}
/**
* @param {shaka.extern.ManifestDB} manifestDb
* @param {boolean} isVideo
* @return {!Array.<MediaKeySystemMediaCapability>}
* @private
*/
static getCapabilities_(manifestDb, isVideo) {
const MimeUtils = shaka.util.MimeUtils;
const ret = [];
for (const stream of manifestDb.streams) {
if (isVideo && stream.type == 'video') {
ret.push({
contentType: MimeUtils.getFullType(stream.mimeType, stream.codecs),
robustness: manifestDb.drmInfo.videoRobustness,
});
} else if (!isVideo && stream.type == 'audio') {
ret.push({
contentType: MimeUtils.getFullType(stream.mimeType, stream.codecs),
robustness: manifestDb.drmInfo.audioRobustness,
});
}
}
return ret;
}
/**
* @param {!shaka.offline.OfflineUri} uri
* @param {shaka.extern.ManifestDB} manifestDb
* @param {!shaka.offline.StorageMuxer} muxer
* @return {!Promise}
* @private
*/
async removeFromDRM_(uri, manifestDb, muxer) {
goog.asserts.assert(this.networkingEngine_, 'Cannot be destroyed');
await shaka.offline.Storage.deleteLicenseFor_(
this.networkingEngine_, this.config_.drm, muxer, manifestDb);
}
/**
* @param {shaka.extern.StorageCell} storage
* @param {!shaka.offline.OfflineUri} uri
* @param {shaka.extern.ManifestDB} manifest
* @return {!Promise}
* @private
*/
removeFromStorage_(storage, uri, manifest) {
/** @type {!Array.<number>} */
const segmentIds = shaka.offline.Storage.getAllSegmentIds_(manifest);
// Count(segments) + Count(manifests)
const toRemove = segmentIds.length + 1;
let removed = 0;
const pendingContent = shaka.offline.StoredContentUtils.fromManifestDB(
uri, manifest);
const onRemove = (key) => {
removed += 1;
this.config_.offline.progressCallback(pendingContent, removed / toRemove);
};
return Promise.all([
storage.removeSegments(segmentIds, onRemove),
storage.removeManifests([uri.key()], onRemove),
]);
}
/**
* Removes any EME sessions that were not successfully removed before. This
* returns whether all the sessions were successfully removed.
*
* @return {!Promise.<boolean>}
* @export
*/
removeEmeSessions() {
return this.startOperation_(this.removeEmeSessions_());
}
/**
* @return {!Promise.<boolean>}
* @private
*/
async removeEmeSessions_() {
this.requireSupport_();
goog.asserts.assert(this.networkingEngine_, 'Cannot be destroyed');
const net = this.networkingEngine_;
const config = this.config_.drm;
/** @type {!shaka.offline.StorageMuxer} */
const muxer = new shaka.offline.StorageMuxer();
/** @type {!shaka.offline.SessionDeleter} */
const deleter = new shaka.offline.SessionDeleter();
let hasRemaining = false;
try {
await muxer.init();
/** @type {!Array.<shaka.extern.EmeSessionStorageCell>} */
const cells = [];
muxer.forEachEmeSessionCell((c) => cells.push(c));
// Run these sequentially to avoid creating too many DrmEngine instances
// and having multiple CDMs alive at once. Some embedded platforms may
// not support that.
for (const sessionIdCell of cells) {
/* eslint-disable no-await-in-loop */
const sessions = await sessionIdCell.getAll();
const deletedSessionIds = await deleter.delete(config, net, sessions);
await sessionIdCell.remove(deletedSessionIds);
if (deletedSessionIds.length != sessions.length) {
hasRemaining = true;
}
/* eslint-enable no-await-in-loop */
}
} finally {
await muxer.destroy();
}
return !hasRemaining;
}
/**
* Lists all the stored content available.
*
* @return {!Promise.<!Array.<shaka.extern.StoredContent>>} A Promise to an
* array of structures representing all stored content. The "offlineUri"
* member of the structure is the URI that should be given to Player.load()
* to play this piece of content offline. The "appMetadata" member is the
* appMetadata argument you passed to store().
* @export
*/
list() {
return this.startOperation_(this.list_());
}
/**
* See |shaka.offline.Storage.list| for details.
*
* @return {!Promise.<!Array.<shaka.extern.StoredContent>>}
* @private
*/
async list_() {
this.requireSupport_();
/** @type {!Array.<shaka.extern.StoredContent>} */
const result = [];
/** @type {!shaka.offline.StorageMuxer} */
const muxer = new shaka.offline.StorageMuxer();
try {
await muxer.init();
let p = Promise.resolve();
muxer.forEachCell((path, cell) => {
p = p.then(async () => {
const manifests = await cell.getAllManifests();
manifests.forEach((manifest, key) => {
const uri = shaka.offline.OfflineUri.manifest(
path.mechanism,
path.cell,
key);
const content = shaka.offline.StoredContentUtils.fromManifestDB(
uri,
manifest);
result.push(content);
});
});
});
await p;
} finally {
await muxer.destroy();
}
return result;
}
/**
* This method is public so that it can be overridden in testing.
*
* @param {string} uri
* @param {shaka.extern.ManifestParser} parser
* @param {shaka.extern.PlayerConfiguration} config
* @return {!Promise.<shaka.extern.Manifest>}
*/
async parseManifest(uri, parser, config) {
let error = null;
const networkingEngine = this.networkingEngine_;
goog.asserts.assert(networkingEngine, 'Should be initialized!');
/** @type {shaka.extern.ManifestParser.PlayerInterface} */
const playerInterface = {
networkingEngine: networkingEngine,
// No need to apply CMCD data for offline requests
modifyManifestRequest: (request, manifestInfo) => {},
modifySegmentRequest: (request, segmentInfo) => {},
// Don't bother filtering now. We will do that later when we have all the
// information we need to filter.
filter: () => Promise.resolve(),
// The responsibility for making mock text streams for closed captions is
// handled inside shaka.offline.OfflineManifestParser, before playback.
makeTextStreamsForClosedCaptions: (manifest) => {},
onTimelineRegionAdded: () => {},
onEvent: () => {},
// Used to capture an error from the manifest parser. We will check the
// error before returning.
onError: (e) => {
error = e;
},
isLowLatencyMode: () => false,
isAutoLowLatencyMode: () => false,
enableLowLatencyMode: () => {},
updateDuration: () => {},
newDrmInfo: (stream) => {},
};
parser.configure(config.manifest);
// We may have been destroyed while we were waiting on |getParser| to
// resolve.
this.ensureNotDestroyed_();
const manifest = await parser.start(uri, playerInterface);
// We may have been destroyed while we were waiting on |start| to
// resolve.
this.ensureNotDestroyed_();
// Get all the streams that are used in the manifest.
const streams =
shaka.offline.Storage.getAllStreamsFromManifest_(manifest);
// Wait for each stream to create their segment indexes.
await Promise.all(shaka.util.Iterables.map(streams, (stream) => {
return stream.createSegmentIndex();
}));
// We may have been destroyed while we were waiting on
// |createSegmentIndex| to resolve for each stream.
this.ensureNotDestroyed_();
// If we saw an error while parsing, surface the error.
if (error) {
throw error;
}
return manifest;
}
/**
* This method is public so that it can be override in testing.
*
* @param {shaka.extern.Manifest} manifest
* @param {function(shaka.util.Error)} onError
* @param {shaka.extern.PlayerConfiguration} config
* @return {!Promise.<!shaka.media.DrmEngine>}
*/
async createDrmEngine(manifest, onError, config) {
goog.asserts.assert(
this.networkingEngine_,
'Cannot call |createDrmEngine| after |destroy|');
/** @type {!shaka.media.DrmEngine} */
const drmEngine = new shaka.media.DrmEngine({
netEngine: this.networkingEngine_,
onError: onError,
onKeyStatus: () => {},
onExpirationUpdated: () => {},
onEvent: () => {},
});
drmEngine.configure(config.drm);
await drmEngine.initForStorage(
manifest.variants, config.offline.usePersistentLicense);
await drmEngine.setServerCertificate();
await drmEngine.createOrLoad();
return drmEngine;
}
/**
* Converts manifest Streams to database Streams.
*
* @param {!shaka.offline.DownloadManager} downloader
* @param {shaka.offline.StreamBandwidthEstimator} estimator
* @param {!shaka.media.DrmEngine} drmEngine
* @param {shaka.extern.Manifest} manifest
* @param {shaka.extern.PlayerConfiguration} config
* @return {{
* streams: !Array.<shaka.extern.StreamDB>,
* toDownload: !Array.<!shaka.offline.DownloadInfo>
* }}
* @private
*/
createStreams_(downloader, estimator, drmEngine, manifest, config) {
// Download infos are stored based on their refId, to dedup them.
/** @type {!Map.<string, !shaka.offline.DownloadInfo>} */
const toDownload = new Map();
// Find the streams we want to download and create a stream db instance
// for each of them.
const streamSet =
shaka.offline.Storage.getAllStreamsFromManifest_(manifest);
const streamDBs = new Map();
for (const stream of streamSet) {
const streamDB = this.createStream_(
downloader, estimator, manifest, stream, config, toDownload);
streamDBs.set(stream.id, streamDB);
}
// Connect streams and variants together.
for (const variant of manifest.variants) {
if (variant.audio) {
streamDBs.get(variant.audio.id).variantIds.push(variant.id);
}
if (variant.video) {
streamDBs.get(variant.video.id).variantIds.push(variant.id);
}
}
return {
streams: Array.from(streamDBs.values()),
toDownload: Array.from(toDownload.values()),
};
}
/**
* Converts a manifest stream to a database stream. This will search the
* segment index and add all the segments to the download infos.
*
* @param {!shaka.offline.DownloadManager} downloader
* @param {shaka.offline.StreamBandwidthEstimator} estimator
* @param {shaka.extern.Manifest} manifest
* @param {shaka.extern.Stream} stream
* @param {shaka.extern.PlayerConfiguration} config
* @param {!Map.<string, !shaka.offline.DownloadInfo>} toDownload
* @return {shaka.extern.StreamDB}
* @private
*/
createStream_(downloader, estimator, manifest, stream, config, toDownload) {
/** @type {shaka.extern.StreamDB} */
const streamDb = {
id: stream.id,
originalId: stream.originalId,
primary: stream.primary,
type: stream.type,
mimeType: stream.mimeType,
codecs: stream.codecs,
frameRate: stream.frameRate,
pixelAspectRatio: stream.pixelAspectRatio,
hdr: stream.hdr,
kind: stream.kind,
language: stream.language,
label: stream.label,
width: stream.width || null,
height: stream.height || null,
encrypted: stream.encrypted,
keyIds: stream.keyIds,
segments: [],
variantIds: [],
roles: stream.roles,
forced: stream.forced,
channelsCount: stream.channelsCount,
audioSamplingRate: stream.audioSamplingRate,
spatialAudio: stream.spatialAudio,
closedCaptions: stream.closedCaptions,
tilesLayout: stream.tilesLayout,
};
const startTime =
manifest.presentationTimeline.getSegmentAvailabilityStart();
const numberOfParallelDownloads = config.offline.numberOfParallelDownloads;
let groupId = 0;
shaka.offline.Storage.forEachSegment_(stream, startTime, (segment) => {
const pendingSegmentRefId =
shaka.offline.DownloadInfo.idForSegmentRef(segment);
let pendingInitSegmentRefId = undefined;
// Set up the download for the segment, which will be downloaded later,
// perhaps in a service worker.
if (!toDownload.has(pendingSegmentRefId)) {
const estimateId = downloader.addDownloadEstimate(
estimator.getSegmentEstimate(stream.id, segment));
const segmentDownload = new shaka.offline.DownloadInfo(
segment,
estimateId,
groupId,
/* isInitSegment= */ false);
toDownload.set(pendingSegmentRefId, segmentDownload);
}
// Set up the download for the init segment, similarly, if there is one.
if (segment.initSegmentReference) {
pendingInitSegmentRefId = shaka.offline.DownloadInfo.idForSegmentRef(
segment.initSegmentReference);
if (!toDownload.has(pendingInitSegmentRefId)) {
const estimateId = downloader.addDownloadEstimate(
estimator.getInitSegmentEstimate(stream.id));
const initDownload = new shaka.offline.DownloadInfo(
segment.initSegmentReference,
estimateId,
groupId,
/* isInitSegment= */ true);
toDownload.set(pendingInitSegmentRefId, initDownload);
}
}
/** @type {!shaka.extern.SegmentDB} */
const segmentDB = {
pendingInitSegmentRefId,
initSegmentKey: pendingInitSegmentRefId ? 0 : null,
startTime: segment.startTime,
endTime: segment.endTime,
appendWindowStart: segment.appendWindowStart,
appendWindowEnd: segment.appendWindowEnd,
timestampOffset: segment.timestampOffset,
tilesLayout: segment.tilesLayout,
pendingSegmentRefId,
dataKey: 0,
};
streamDb.segments.push(segmentDB);
groupId = (groupId + 1) % numberOfParallelDownloads;
});
return streamDb;
}
/**
* @param {shaka.extern.Stream} stream
* @param {number} startTime
* @param {function(!shaka.media.SegmentReference)} callback
* @private
*/
static forEachSegment_(stream, startTime, callback) {
/** @type {?number} */
let i = stream.segmentIndex.find(startTime);
if (i == null) {
return;
}
/** @type {?shaka.media.SegmentReference} */
let ref = stream.segmentIndex.get(i);
while (ref) {
callback(ref);
ref = stream.segmentIndex.get(++i);
}
}
/**
* Throws an error if the object is destroyed.
* @private
*/
ensureNotDestroyed_() {
if (this.destroyer_.destroyed()) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.STORAGE,
shaka.util.Error.Code.OPERATION_ABORTED);
}
}
/**
* Used by functions that need storage support to ensure that the current
* platform has storage support before continuing. This should only be
* needed to be used at the start of public methods.
*
* @private
*/
requireSupport_() {
if (!shaka.offline.Storage.support()) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.STORAGE,
shaka.util.Error.Code.STORAGE_NOT_SUPPORTED);
}
}
/**
* Perform an action. Track the action's progress so that when we destroy
* we will wait until all the actions have completed before allowing destroy
* to resolve.
*
* @param {!Promise<T>} action
* @return {!Promise<T>}
* @template T
* @private
*/
async startOperation_(action) {
this.openOperations_.push(action);
try {
// Await |action| so we can use the finally statement to remove |action|
// from |openOperations_| when we still have a reference to |action|.
return await action;
} finally {
shaka.util.ArrayUtils.remove(this.openOperations_, action);
}
}
/**
* The equivalent of startOperation_, but for abortable operations.
*
* @param {!shaka.extern.IAbortableOperation<T>} action
* @return {!shaka.extern.IAbortableOperation<T>}
* @template T
* @private
*/
startAbortableOperation_(action) {
const promise = action.promise;
this.openOperations_.push(promise);
// Remove the open operation once the action has completed. So that we
// can still return the AbortableOperation, this is done using a |finally|
// block, rather than awaiting the result.
return action.finally(() => {
shaka.util.ArrayUtils.remove(this.openOperations_, promise);
});
}
/**
* @param {shaka.extern.ManifestDB} manifest
* @return {!Array.<number>}
* @private
*/
static getAllSegmentIds_(manifest) {
/** @type {!Set.<number>} */
const ids = new Set();
// Get every segment for every stream in the manifest.
for (const stream of manifest.streams) {
for (const segment of stream.segments) {
if (segment.initSegmentKey != null) {
ids.add(segment.initSegmentKey);
}
ids.add(segment.dataKey);
}
}
return Array.from(ids);
}
/**
* Delete the on-disk storage and all the content it contains. This should not
* be done in normal circumstances. Only do it when storage is rendered
* unusable, such as by a version mismatch. No business logic will be run, and
* licenses will not be released.
*
* @return {!Promise}
* @export
*/
static async deleteAll() {
/** @type {!shaka.offline.StorageMuxer} */
const muxer = new shaka.offline.StorageMuxer();
try {
// Wipe all content from all storage mechanisms.
await muxer.erase();
} finally {
// Destroy the muxer, whether or not erase() succeeded.
await muxer.destroy();
}
}
/**
* @param {!shaka.net.NetworkingEngine} net
* @param {!shaka.extern.DrmConfiguration} drmConfig
* @param {!shaka.offline.StorageMuxer} muxer
* @param {shaka.extern.ManifestDB} manifestDb
* @return {!Promise}
* @private
*/
static async deleteLicenseFor_(net, drmConfig, muxer, manifestDb) {
if (!manifestDb.drmInfo) {
return;
}
const sessionIdCell = muxer.getEmeSessionCell();
/** @type {!Array.<shaka.extern.EmeSessionDB>} */
const sessions = manifestDb.sessionIds.map((sessionId) => {
return {
sessionId: sessionId,
keySystem: manifestDb.drmInfo.keySystem,
licenseUri: manifestDb.drmInfo.licenseServerUri,
serverCertificate: manifestDb.drmInfo.serverCertificate,
audioCapabilities: shaka.offline.Storage.getCapabilities_(
manifestDb,
/* isVideo= */ false),
videoCapabilities: shaka.offline.Storage.getCapabilities_(
manifestDb,
/* isVideo= */ true),
};
});
// Try to delete the sessions; any sessions that weren't deleted get stored
// in the database so we can try to remove them again later. This allows us
// to still delete the stored content but not "forget" about these sessions.
// Later, we can remove the sessions to free up space.
const deleter = new shaka.offline.SessionDeleter();
const deletedSessionIds = await deleter.delete(drmConfig, net, sessions);
await sessionIdCell.remove(deletedSessionIds);
await sessionIdCell.add(sessions.filter(
(session) => !deletedSessionIds.includes(session.sessionId)));
}
/**
* Get the set of all streams in |manifest|.
*
* @param {shaka.extern.Manifest} manifest
* @return {!Set.<shaka.extern.Stream>}
* @private
*/
static getAllStreamsFromManifest_(manifest) {
/** @type {!Set.<shaka.extern.Stream>} */
const set = new Set();
for (const text of manifest.textStreams) {
set.add(text);
}
for (const image of manifest.imageStreams) {
set.add(image);
}
for (const variant of manifest.variants) {
if (variant.audio) {
set.add(variant.audio);
}
if (variant.video) {
set.add(variant.video);
}
}
return set;
}
/**
* Go over a manifest and issue warnings for any suspicious properties.
*
* @param {shaka.extern.Manifest} manifest
* @private
*/
static validateManifest_(manifest) {
const videos = new Set(manifest.variants.map((v) => v.video));
const audios = new Set(manifest.variants.map((v) => v.audio));
const texts = manifest.textStreams;
if (videos.size > 1) {
shaka.log.warning('Multiple video tracks selected to be stored');
}
for (const audio1 of audios) {
for (const audio2 of audios) {
if (audio1 != audio2 && audio1.language == audio2.language) {
shaka.log.warning(
'Similar audio tracks were selected to be stored',
audio1.id,
audio2.id);
}
}
}
for (const text1 of texts) {
for (const text2 of texts) {
if (text1 != text2 && text1.language == text2.language) {
shaka.log.warning(
'Similar text tracks were selected to be stored',
text1.id,
text2.id);
}
}
}
}
};
shaka.offline.Storage.defaultSystemIds_ = new Map()
.set('org.w3.clearkey', '1077efecc0b24d02ace33c1e52e2fb4b')
.set('com.widevine.alpha', 'edef8ba979d64acea3c827dcd51d21ed')
.set('com.microsoft.playready', '9a04f07998404286ab92e65be0885f95')
.set('com.microsoft.playready.recommendation',
'9a04f07998404286ab92e65be0885f95')
.set('com.microsoft.playready.software',
'9a04f07998404286ab92e65be0885f95')
.set('com.microsoft.playready.hardware',
'9a04f07998404286ab92e65be0885f95')
.set('com.adobe.primetime', 'f239e769efa348509c16a903c6932efb');
shaka.Player.registerSupportPlugin('offline', shaka.offline.Storage.support);