/*! @license
* Shaka Player
* Copyright 2023 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
goog.provide('shaka.media.PreloadManager');
goog.require('goog.asserts');
goog.require('shaka.log');
goog.require('shaka.util.Error');
goog.require('shaka.media.ManifestFilterer');
goog.require('shaka.media.ManifestParser');
goog.require('shaka.util.PublicPromise');
goog.require('shaka.media.PreferenceBasedCriteria');
goog.require('shaka.util.Stats');
goog.require('shaka.media.SegmentPrefetch');
goog.require('shaka.util.IDestroyable');
goog.require('shaka.net.NetworkingEngine');
goog.require('shaka.media.AdaptationSetCriteria');
goog.require('shaka.media.DrmEngine');
goog.require('shaka.media.RegionTimeline');
goog.require('shaka.media.QualityObserver');
goog.require('shaka.util.StreamUtils');
goog.require('shaka.media.StreamingEngine');
goog.require('shaka.media.SegmentPrefetch');
goog.require('shaka.util.ConfigUtils');
goog.require('shaka.util.FakeEvent');
goog.require('shaka.util.FakeEventTarget');
goog.require('shaka.util.ObjectUtils');
goog.require('shaka.util.PlayerConfiguration');
/**
* @implements {shaka.util.IDestroyable}
* @export
*/
shaka.media.PreloadManager = class extends shaka.util.FakeEventTarget {
/**
* @param {string} assetUri
* @param {?string} mimeType
* @param {?number} startTime
* @param {*} playerInterface
*/
constructor(assetUri, mimeType, startTime, playerInterface) {
super();
// Making the playerInterface a * and casting it to the right type allows
// for the PlayerInterface for this class to not be exported.
// Unfortunately, the constructor is exported by default.
const typedPlayerInterface =
/** @type {!shaka.media.PreloadManager.PlayerInterface} */ (
playerInterface);
/** @private {string} */
this.assetUri_ = assetUri;
/** @private {?string} */
this.mimeType_ = mimeType;
/** @private {!shaka.net.NetworkingEngine} */
this.networkingEngine_ = typedPlayerInterface.networkingEngine;
/** @private {?number} */
this.startTime_ = startTime;
/** @private {?shaka.media.AdaptationSetCriteria} */
this.currentAdaptationSetCriteria_ = null;
/** @private {number} */
this.startTimeOfDrm_ = 0;
/** @private {function():!shaka.media.DrmEngine} */
this.createDrmEngine_ = typedPlayerInterface.createDrmEngine;
/** @private {!shaka.media.ManifestFilterer} */
this.manifestFilterer_ = typedPlayerInterface.manifestFilterer;
/** @private {!shaka.extern.ManifestParser.PlayerInterface} */
this.manifestPlayerInterface_ =
typedPlayerInterface.manifestPlayerInterface;
/** @private {!shaka.extern.PlayerConfiguration} */
this.config_ = typedPlayerInterface.config;
/** @private {?shaka.extern.Manifest} */
this.manifest_ = null;
/** @private {?shaka.extern.ManifestParser.Factory} */
this.parserFactory_ = null;
/** @private {?shaka.extern.ManifestParser} */
this.parser_ = null;
/** @private {boolean} */
this.parserEntrusted_ = false;
/** @private {!shaka.media.RegionTimeline} */
this.regionTimeline_ = typedPlayerInterface.regionTimeline;
/** @private {boolean} */
this.regionTimelineEntrusted_ = false;
/** @private {?shaka.media.DrmEngine} */
this.drmEngine_ = null;
/** @private {boolean} */
this.drmEngineEntrusted_ = false;
/** @private {?shaka.extern.AbrManager.Factory} */
this.abrManagerFactory_ = null;
/** @private {shaka.extern.AbrManager} */
this.abrManager_ = null;
/** @private {boolean} */
this.abrManagerEntrusted_ = false;
/** @private {!Map.<number, shaka.media.SegmentPrefetch>} */
this.segmentPrefetchById_ = new Map();
/** @private {boolean} */
this.segmentPrefetchEntrusted_ = false;
/** @private {?shaka.media.QualityObserver} */
this.qualityObserver_ = typedPlayerInterface.qualityObserver;
/** @private {!shaka.util.Stats} */
this.stats_ = new shaka.util.Stats();
/** @private {!shaka.util.PublicPromise} */
this.successPromise_ = new shaka.util.PublicPromise();
/** @private {?shaka.util.FakeEventTarget} */
this.eventHandoffTarget_ = null;
/** @private {boolean} */
this.destroyed_ = false;
/** @private {boolean} */
this.allowPrefetch_ = typedPlayerInterface.allowPrefetch;
/** @private {?shaka.extern.Variant} */
this.prefetchedVariant_ = null;
/** @private {boolean} */
this.allowMakeAbrManager_ = typedPlayerInterface.allowMakeAbrManager;
/** @private {boolean} */
this.hasBeenAttached_ = false;
/** @private {?Array.<function()>} */
this.queuedOperations_ = [];
/** @private {?Array.<function()>} */
this.latePhaseQueuedOperations_ = [];
}
/**
* @param {boolean} latePhase
* @param {function()} callback
*/
addQueuedOperation(latePhase, callback) {
const queue =
latePhase ? this.latePhaseQueuedOperations_ : this.queuedOperations_;
if (queue) {
queue.push(callback);
} else {
callback();
}
}
/** Calls all late phase queued operations, and stops queueing them. */
stopQueuingLatePhaseQueuedOperations() {
if (this.latePhaseQueuedOperations_) {
for (const callback of this.latePhaseQueuedOperations_) {
callback();
}
}
this.latePhaseQueuedOperations_ = null;
}
/** @param {!shaka.util.FakeEventTarget} eventHandoffTarget */
setEventHandoffTarget(eventHandoffTarget) {
this.eventHandoffTarget_ = eventHandoffTarget;
this.hasBeenAttached_ = true;
// Also call all queued operations, and stop queuing them in the future.
if (this.queuedOperations_) {
for (const callback of this.queuedOperations_) {
callback();
}
}
this.queuedOperations_ = null;
}
/** @param {number} offset */
setOffsetToStartTime(offset) {
if (this.startTime_ && offset) {
this.startTime_ += offset;
}
}
/** @return {?number} */
getStartTime() {
return this.startTime_;
}
/** @return {number} */
getStartTimeOfDRM() {
return this.startTimeOfDrm_;
}
/** @return {?string} */
getMimeType() {
return this.mimeType_;
}
/** @return {string} */
getAssetUri() {
return this.assetUri_;
}
/** @return {?shaka.extern.Manifest} */
getManifest() {
return this.manifest_;
}
/** @return {?shaka.extern.ManifestParser.Factory} */
getParserFactory() {
return this.parserFactory_;
}
/** @return {?shaka.media.AdaptationSetCriteria} */
getCurrentAdaptationSetCriteria() {
return this.currentAdaptationSetCriteria_;
}
/** @return {?shaka.extern.AbrManager.Factory} */
getAbrManagerFactory() {
return this.abrManagerFactory_;
}
/**
* Gets the abr manager, if it exists. Also marks that the abr manager should
* not be stopped if this manager is destroyed.
* @return {?shaka.extern.AbrManager}
*/
receiveAbrManager() {
this.abrManagerEntrusted_ = true;
return this.abrManager_;
}
/**
* @return {?shaka.extern.AbrManager}
*/
getAbrManager() {
return this.abrManager_;
}
/**
* Gets the parser, if it exists. Also marks that the parser should not be
* stopped if this manager is destroyed.
* @return {?shaka.extern.ManifestParser}
*/
receiveParser() {
this.parserEntrusted_ = true;
return this.parser_;
}
/**
* @return {?shaka.extern.ManifestParser}
*/
getParser() {
return this.parser_;
}
/**
* Gets the region timeline, if it exists. Also marks that the timeline should
* not be released if this manager is destroyed.
* @return {?shaka.media.RegionTimeline}
*/
receiveRegionTimeline() {
this.regionTimelineEntrusted_ = true;
return this.regionTimeline_;
}
/**
* @return {?shaka.media.RegionTimeline}
*/
getRegionTimeline() {
return this.regionTimeline_;
}
/** @return {?shaka.media.QualityObserver} */
getQualityObserver() {
return this.qualityObserver_;
}
/** @return {!shaka.util.Stats} */
getStats() {
return this.stats_;
}
/** @return {!shaka.media.ManifestFilterer} */
getManifestFilterer() {
return this.manifestFilterer_;
}
/**
* Gets the drm engine, if it exists. Also marks that the drm engine should
* not be destroyed if this manager is destroyed.
* @return {?shaka.media.DrmEngine}
*/
receiveDrmEngine() {
this.drmEngineEntrusted_ = true;
return this.drmEngine_;
}
/**
* @return {?shaka.media.DrmEngine}
*/
getDrmEngine() {
return this.drmEngine_;
}
/**
* @return {?shaka.extern.Variant}
*/
getPrefetchedVariant() {
return this.prefetchedVariant_;
}
/**
* Gets the SegmentPrefetch objects for the initial stream ids. Also marks
* that those objects should not be aborted if this manager is destroyed.
* @return {!Map.<number, shaka.media.SegmentPrefetch>}
*/
receiveSegmentPrefetchesById() {
this.segmentPrefetchEntrusted_ = true;
return this.segmentPrefetchById_;
}
/**
* @param {?shaka.extern.AbrManager} abrManager
* @param {?shaka.extern.AbrManager.Factory} abrFactory
*/
attachAbrManager(abrManager, abrFactory) {
this.abrManager_ = abrManager;
this.abrManagerFactory_ = abrFactory;
}
/**
* @param {?shaka.media.AdaptationSetCriteria} adaptationSetCriteria
*/
attachAdaptationSetCriteria(adaptationSetCriteria) {
this.currentAdaptationSetCriteria_ = adaptationSetCriteria;
}
/**
* @param {!shaka.extern.Manifest} manifest
* @param {!shaka.extern.ManifestParser} parser
* @param {!shaka.extern.ManifestParser.Factory} parserFactory
*/
attachManifest(manifest, parser, parserFactory) {
this.manifest_ = manifest;
this.parser_ = parser;
this.parserFactory_ = parserFactory;
}
/**
* Starts the process of loading the asset.
* Success or failure will be measured through waitForFinish()
*/
start() {
(async () => {
// Force a context switch, to give the player a chance to hook up events
// immediately if desired.
await Promise.resolve();
// Perform the preloading process.
try {
await this.parseManifestInner_();
this.throwIfDestroyed_();
await this.initializeDrmInner_();
this.throwIfDestroyed_();
await this.chooseInitialVariantInner_();
this.throwIfDestroyed_();
this.successPromise_.resolve();
} catch (error) {
this.successPromise_.reject(error);
}
})();
}
/**
* @param {!Event} event
* @return {boolean}
* @override
*/
dispatchEvent(event) {
if (this.eventHandoffTarget_) {
return this.eventHandoffTarget_.dispatchEvent(event);
} else {
return super.dispatchEvent(event);
}
}
/**
* @param {!shaka.util.Error} error
*/
onError(error) {
if (error.severity === shaka.util.Error.Severity.CRITICAL) {
// Cancel the loading process.
this.successPromise_.reject(error);
this.destroy();
}
const eventName = shaka.util.FakeEvent.EventName.Error;
const event = this.makeEvent_(eventName, (new Map()).set('detail', error));
this.dispatchEvent(event);
if (event.defaultPrevented) {
error.handled = true;
}
}
/**
* Throw if destroyed, to interrupt processes with a recognizable error.
*
* @private
*/
throwIfDestroyed_() {
if (this.isDestroyed()) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.PLAYER,
shaka.util.Error.Code.OBJECT_DESTROYED);
}
}
/**
* Makes a fires an event corresponding to entering a state of the loading
* process.
* @param {string} nodeName
* @private
*/
makeStateChangeEvent_(nodeName) {
this.dispatchEvent(new shaka.util.FakeEvent(
/* name= */ shaka.util.FakeEvent.EventName.OnStateChange,
/* data= */ (new Map()).set('state', nodeName)));
}
/**
* @param {!shaka.util.FakeEvent.EventName} name
* @param {Map.<string, Object>=} data
* @return {!shaka.util.FakeEvent}
* @private
*/
makeEvent_(name, data) {
return new shaka.util.FakeEvent(name, data);
}
/**
* Pick and initialize a manifest parser, then have it download and parse the
* manifest.
*
* @return {!Promise}
* @private
*/
async parseManifestInner_() {
this.makeStateChangeEvent_('manifest-parser');
if (!this.parser_) {
// Create the parser that we will use to parse the manifest.
this.parserFactory_ = shaka.media.ManifestParser.getFactory(
this.assetUri_, this.mimeType_);
goog.asserts.assert(this.parserFactory_, 'Must have manifest parser');
this.parser_ = this.parserFactory_();
this.parser_.configure(this.config_.manifest);
}
const startTime = Date.now() / 1000;
this.makeStateChangeEvent_('manifest');
if (!this.manifest_) {
this.manifest_ = await this.parser_.start(
this.assetUri_, this.manifestPlayerInterface_);
}
// This event is fired after the manifest is parsed, but before any
// filtering takes place.
const event =
this.makeEvent_(shaka.util.FakeEvent.EventName.ManifestParsed);
this.dispatchEvent(event);
// We require all manifests to have at least one variant.
if (this.manifest_.variants.length == 0) {
throw new shaka.util.Error(
shaka.util.Error.Severity.CRITICAL,
shaka.util.Error.Category.MANIFEST,
shaka.util.Error.Code.NO_VARIANTS);
}
// Make sure that all variants are either: audio-only, video-only, or
// audio-video.
shaka.media.PreloadManager.filterForAVVariants_(this.manifest_);
const now = Date.now() / 1000;
const delta = now - startTime;
this.stats_.setManifestTime(delta);
}
/**
* Initializes the DRM engine.
*
* @return {!Promise}
* @private
*/
async initializeDrmInner_() {
goog.asserts.assert(
this.manifest_, 'The manifest should already be parsed.');
this.makeStateChangeEvent_('drm-engine');
this.startTimeOfDrm_ = Date.now() / 1000;
this.drmEngine_ = this.createDrmEngine_();
this.manifestFilterer_.setDrmEngine(this.drmEngine_);
this.drmEngine_.configure(this.config_.drm);
const tracksChangedInitial = this.manifestFilterer_.applyRestrictions(
this.manifest_);
if (tracksChangedInitial) {
const event = this.makeEvent_(
shaka.util.FakeEvent.EventName.TracksChanged);
await Promise.resolve();
this.throwIfDestroyed_();
this.dispatchEvent(event);
}
const playableVariants = shaka.util.StreamUtils.getPlayableVariants(
this.manifest_.variants);
await this.drmEngine_.initForPlayback(
playableVariants,
this.manifest_.offlineSessionIds);
this.throwIfDestroyed_();
// Now that we have drm information, filter the manifest (again) so that
// we can ensure we only use variants with the selected key system.
const tracksChangedAfter = await this.manifestFilterer_.filterManifest(
this.manifest_);
if (tracksChangedAfter) {
const event = this.makeEvent_(
shaka.util.FakeEvent.EventName.TracksChanged);
await Promise.resolve();
this.dispatchEvent(event);
}
}
/** @param {!shaka.extern.PlayerConfiguration} config */
reconfigure(config) {
this.config_ = config;
}
/**
* @param {string} name
* @param {*=} value
*/
configure(name, value) {
const config = shaka.util.ConfigUtils.convertToConfigObject(name, value);
shaka.util.PlayerConfiguration.mergeConfigObjects(this.config_, config);
}
/**
* Return a copy of the current configuration.
*
* @return {shaka.extern.PlayerConfiguration}
*/
getConfiguration() {
return shaka.util.ObjectUtils.cloneObject(this.config_);
}
/**
* Performs a final filtering of the manifest, and chooses the initial
* variant.
*
* @private
*/
chooseInitialVariantInner_() {
goog.asserts.assert(
this.manifest_, 'The manifest should already be parsed.');
// This step does not have any associated events, as it is only part of the
// "load" state in the old state graph.
if (!this.currentAdaptationSetCriteria_) {
// Copy preferred languages from the config again, in case the config was
// changed between construction and playback.
this.currentAdaptationSetCriteria_ =
new shaka.media.PreferenceBasedCriteria(
this.config_.preferredAudioLanguage,
this.config_.preferredVariantRole,
this.config_.preferredAudioChannelCount,
this.config_.preferredVideoHdrLevel,
this.config_.preferSpatialAudio,
this.config_.preferredVideoLayout,
this.config_.preferredAudioLabel,
this.config_.preferredVideoLabel,
this.config_.mediaSource.codecSwitchingStrategy,
this.config_.manifest.dash.enableAudioGroups);
}
// Make the ABR manager.
if (this.allowMakeAbrManager_) {
const abrFactory = this.config_.abrFactory;
this.abrManagerFactory_ = abrFactory;
this.abrManager_ = abrFactory();
this.abrManager_.configure(this.config_.abr);
}
if (this.allowPrefetch_) {
const isLive = this.manifest_.presentationTimeline.isLive();
// Prefetch segments for the predicted first variant.
// We start these here, but don't wait for them; it's okay to start the
// full load process while the segments are being prefetched.
const playableVariants = shaka.util.StreamUtils.getPlayableVariants(
this.manifest_.variants);
const adaptationSet = this.currentAdaptationSetCriteria_.create(
playableVariants);
// Guess what the first variant will be, based on a SimpleAbrManager.
this.abrManager_.configure(this.config_.abr);
this.abrManager_.setVariants(Array.from(adaptationSet.values()));
const variant =
this.abrManager_.chooseVariant(/* preferFastSwitching= */ true);
if (variant) {
this.prefetchedVariant_ = variant;
if (variant.video) {
this.makePrefetchForStream_(variant.video, isLive);
}
if (variant.audio) {
this.makePrefetchForStream_(variant.audio, isLive);
}
}
}
}
/**
* @param {!shaka.extern.Stream} stream
* @param {boolean} isLive
* @return {!Promise}
* @private
*/
async makePrefetchForStream_(stream, isLive) {
// Use the prefetch limit from the config if this is set, otherwise use 2.
const prefetchLimit = this.config_.streaming.segmentPrefetchLimit || 2;
const prefetch = new shaka.media.SegmentPrefetch(
prefetchLimit, stream, (reference, stream, streamDataCallback) => {
return shaka.media.StreamingEngine.dispatchFetch(
reference, stream, streamDataCallback || null,
this.config_.streaming.retryParameters, this.networkingEngine_);
}, /* reverse= */ false);
this.segmentPrefetchById_.set(stream.id, prefetch);
// Start prefetching a bit.
await stream.createSegmentIndex();
const startTime = this.startTime_ || 0;
const prefetchSegmentIterator =
stream.segmentIndex.getIteratorForTime(startTime);
let prefetchSegment =
prefetchSegmentIterator ? prefetchSegmentIterator.current() : null;
if (!prefetchSegment) {
// If we can't get a segment at the desired spot, at least get a segment,
// so we can get the init segment.
prefetchSegment = stream.segmentIndex.get(0);
}
if (prefetchSegment) {
if (isLive) {
// Preload only the init segment for Live
if (prefetchSegment.initSegmentReference) {
prefetch.prefetchInitSegment(prefetchSegment.initSegmentReference);
}
} else {
// Preload a segment, too... either the first segment, or the segment
// that corresponds with this.startTime_, as appropriate.
// Note: this method also preload the init segment
prefetch.prefetchSegmentsByTime(prefetchSegment.startTime);
}
}
}
/**
* Waits for the loading to be finished (or to fail with an error).
* @return {!Promise}
* @export
*/
waitForFinish() {
return this.successPromise_;
}
/**
* Releases or stops all non-entrusted resources.
*
* @override
* @export
*/
async destroy() {
this.destroyed_ = true;
if (this.parser_ && !this.parserEntrusted_) {
await this.parser_.stop();
}
if (this.abrManager_ && !this.abrManagerEntrusted_) {
await this.abrManager_.stop();
}
if (this.regionTimeline_ && !this.regionTimelineEntrusted_) {
this.regionTimeline_.release();
}
if (this.drmEngine_ && !this.drmEngineEntrusted_) {
await this.drmEngine_.destroy();
}
if (this.segmentPrefetchById_.size > 0 && !this.segmentPrefetchEntrusted_) {
for (const segmentPrefetch of this.segmentPrefetchById_.values()) {
segmentPrefetch.clearAll();
}
}
// this.eventHandoffTarget_ is not unset, so that events and errors fired
// after the preload manager is destroyed will still be routed to the
// player, if it was once linked up.
}
/** @return {boolean} */
isDestroyed() {
return this.destroyed_;
}
/** @return {boolean} */
hasBeenAttached() {
return this.hasBeenAttached_;
}
/**
* Take a series of variants and ensure that they only contain one type of
* variant. The different options are:
* 1. Audio-Video
* 2. Audio-Only
* 3. Video-Only
*
* A manifest can only contain a single type because once we initialize media
* source to expect specific streams, it must always have content for those
* streams. If we were to start with audio+video and switch to an audio-only
* variant, media source would block waiting for video content.
*
* @param {shaka.extern.Manifest} manifest
* @private
*/
static filterForAVVariants_(manifest) {
const isAVVariant = (variant) => {
// Audio-video variants may include both streams separately or may be
// single multiplexed streams with multiple codecs.
return (variant.video && variant.audio) ||
(variant.video && variant.video.codecs.includes(','));
};
if (manifest.variants.some(isAVVariant)) {
shaka.log.debug('Found variant with audio and video content, ' +
'so filtering out audio-only content.');
manifest.variants = manifest.variants.filter(isAVVariant);
}
}
};
/**
* @typedef {{
* config: !shaka.extern.PlayerConfiguration,
* manifestPlayerInterface: !shaka.extern.ManifestParser.PlayerInterface,
* regionTimeline: !shaka.media.RegionTimeline,
* qualityObserver: ?shaka.media.QualityObserver,
* createDrmEngine: function():!shaka.media.DrmEngine,
* networkingEngine: !shaka.net.NetworkingEngine,
* manifestFilterer: !shaka.media.ManifestFilterer,
* allowPrefetch: boolean,
* allowMakeAbrManager: boolean
* }}
*
* @property {!shaka.extern.PlayerConfiguration} config
* @property {!shaka.extern.ManifestParser.PlayerInterface}
* manifestPlayerInterface
* @property {!shaka.media.RegionTimeline} regionTimeline
* @property {?shaka.media.QualityObserver} qualityObserver
* @property {function():!shaka.media.DrmEngine} createDrmEngine
* @property {!shaka.net.NetworkingEngine} networkingEngine
* @property {!shaka.media.ManifestFilterer} manifestFilterer
* @property {boolean} allowPrefetch
* @property {boolean} allowMakeAbrManager
*/
shaka.media.PreloadManager.PlayerInterface;