862 lines
26 KiB
JavaScript
862 lines
26 KiB
JavaScript
/**
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* @file playlist-loader.js
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*
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* A state machine that manages the loading, caching, and updating of
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* M3U8 playlists.
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*
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*/
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import { resolveUrl, resolveManifestRedirect } from './resolve-url';
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import videojs from 'video.js';
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import window from 'global/window';
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import logger from './util/logger';
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import {
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parseManifest,
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addPropertiesToMaster,
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masterForMedia,
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setupMediaPlaylist,
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forEachMediaGroup
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} from './manifest';
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import {getKnownPartCount} from './playlist.js';
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const { mergeOptions, EventTarget } = videojs;
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const addLLHLSQueryDirectives = (uri, media) => {
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if (media.endList) {
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return uri;
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}
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const query = [];
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if (media.serverControl && media.serverControl.canBlockReload) {
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const {preloadSegment} = media;
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// next msn is a zero based value, length is not.
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let nextMSN = media.mediaSequence + media.segments.length;
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// If preload segment has parts then it is likely
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// that we are going to request a part of that preload segment.
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// the logic below is used to determine that.
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if (preloadSegment) {
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const parts = preloadSegment.parts || [];
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// _HLS_part is a zero based index
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const nextPart = getKnownPartCount(media) - 1;
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// if nextPart is > -1 and not equal to just the
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// length of parts, then we know we had part preload hints
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// and we need to add the _HLS_part= query
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if (nextPart > -1 && nextPart !== (parts.length - 1)) {
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// add existing parts to our preload hints
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query.push(`_HLS_part=${nextPart}`);
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}
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// this if statement makes sure that we request the msn
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// of the preload segment if:
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// 1. the preload segment had parts (and was not yet a full segment)
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// but was added to our segments array
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// 2. the preload segment had preload hints for parts that are not in
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// the manifest yet.
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// in all other cases we want the segment after the preload segment
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// which will be given by using media.segments.length because it is 1 based
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// rather than 0 based.
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if (nextPart > -1 || parts.length) {
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nextMSN--;
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}
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}
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// add _HLS_msn= in front of any _HLS_part query
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query.unshift(`_HLS_msn=${nextMSN}`);
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}
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if (media.serverControl && media.serverControl.canSkipUntil) {
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// add _HLS_skip= infront of all other queries.
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query.unshift('_HLS_skip=' + (media.serverControl.canSkipDateranges ? 'v2' : 'YES'));
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}
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query.forEach(function(str, i) {
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const symbol = i === 0 ? '?' : '&';
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uri += `${symbol}${str}`;
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});
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return uri;
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};
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/**
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* Returns a new segment object with properties and
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* the parts array merged.
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*
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* @param {Object} a the old segment
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* @param {Object} b the new segment
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*
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* @return {Object} the merged segment
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*/
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export const updateSegment = (a, b) => {
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if (!a) {
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return b;
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}
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const result = mergeOptions(a, b);
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// if only the old segment has preload hints
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// and the new one does not, remove preload hints.
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if (a.preloadHints && !b.preloadHints) {
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delete result.preloadHints;
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}
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// if only the old segment has parts
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// then the parts are no longer valid
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if (a.parts && !b.parts) {
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delete result.parts;
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// if both segments have parts
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// copy part propeties from the old segment
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// to the new one.
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} else if (a.parts && b.parts) {
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for (let i = 0; i < b.parts.length; i++) {
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if (a.parts && a.parts[i]) {
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result.parts[i] = mergeOptions(a.parts[i], b.parts[i]);
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}
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}
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}
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// set skipped to false for segments that have
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// have had information merged from the old segment.
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if (!a.skipped && b.skipped) {
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result.skipped = false;
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}
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// set preload to false for segments that have
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// had information added in the new segment.
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if (a.preload && !b.preload) {
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result.preload = false;
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}
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return result;
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};
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/**
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* Returns a new array of segments that is the result of merging
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* properties from an older list of segments onto an updated
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* list. No properties on the updated playlist will be ovewritten.
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*
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* @param {Array} original the outdated list of segments
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* @param {Array} update the updated list of segments
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* @param {number=} offset the index of the first update
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* segment in the original segment list. For non-live playlists,
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* this should always be zero and does not need to be
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* specified. For live playlists, it should be the difference
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* between the media sequence numbers in the original and updated
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* playlists.
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* @return {Array} a list of merged segment objects
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*/
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export const updateSegments = (original, update, offset) => {
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const oldSegments = original.slice();
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const newSegments = update.slice();
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offset = offset || 0;
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const result = [];
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let currentMap;
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for (let newIndex = 0; newIndex < newSegments.length; newIndex++) {
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const oldSegment = oldSegments[newIndex + offset];
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const newSegment = newSegments[newIndex];
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if (oldSegment) {
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currentMap = oldSegment.map || currentMap;
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result.push(updateSegment(oldSegment, newSegment));
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} else {
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// carry over map to new segment if it is missing
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if (currentMap && !newSegment.map) {
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newSegment.map = currentMap;
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}
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result.push(newSegment);
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}
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}
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return result;
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};
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export const resolveSegmentUris = (segment, baseUri) => {
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// preloadSegment will not have a uri at all
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// as the segment isn't actually in the manifest yet, only parts
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if (!segment.resolvedUri && segment.uri) {
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segment.resolvedUri = resolveUrl(baseUri, segment.uri);
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}
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if (segment.key && !segment.key.resolvedUri) {
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segment.key.resolvedUri = resolveUrl(baseUri, segment.key.uri);
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}
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if (segment.map && !segment.map.resolvedUri) {
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segment.map.resolvedUri = resolveUrl(baseUri, segment.map.uri);
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}
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if (segment.map && segment.map.key && !segment.map.key.resolvedUri) {
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segment.map.key.resolvedUri = resolveUrl(baseUri, segment.map.key.uri);
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}
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if (segment.parts && segment.parts.length) {
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segment.parts.forEach((p) => {
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if (p.resolvedUri) {
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return;
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}
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p.resolvedUri = resolveUrl(baseUri, p.uri);
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});
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}
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if (segment.preloadHints && segment.preloadHints.length) {
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segment.preloadHints.forEach((p) => {
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if (p.resolvedUri) {
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return;
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}
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p.resolvedUri = resolveUrl(baseUri, p.uri);
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});
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}
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};
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const getAllSegments = function(media) {
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const segments = media.segments || [];
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const preloadSegment = media.preloadSegment;
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// a preloadSegment with only preloadHints is not currently
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// a usable segment, only include a preloadSegment that has
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// parts.
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if (preloadSegment && preloadSegment.parts && preloadSegment.parts.length) {
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// if preloadHints has a MAP that means that the
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// init segment is going to change. We cannot use any of the parts
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// from this preload segment.
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if (preloadSegment.preloadHints) {
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for (let i = 0; i < preloadSegment.preloadHints.length; i++) {
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if (preloadSegment.preloadHints[i].type === 'MAP') {
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return segments;
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}
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}
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}
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// set the duration for our preload segment to target duration.
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preloadSegment.duration = media.targetDuration;
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preloadSegment.preload = true;
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segments.push(preloadSegment);
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}
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return segments;
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};
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// consider the playlist unchanged if the playlist object is the same or
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// the number of segments is equal, the media sequence number is unchanged,
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// and this playlist hasn't become the end of the playlist
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export const isPlaylistUnchanged = (a, b) => a === b ||
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(a.segments && b.segments && a.segments.length === b.segments.length &&
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a.endList === b.endList &&
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a.mediaSequence === b.mediaSequence);
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/**
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* Returns a new master playlist that is the result of merging an
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* updated media playlist into the original version. If the
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* updated media playlist does not match any of the playlist
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* entries in the original master playlist, null is returned.
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*
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* @param {Object} master a parsed master M3U8 object
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* @param {Object} media a parsed media M3U8 object
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* @return {Object} a new object that represents the original
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* master playlist with the updated media playlist merged in, or
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* null if the merge produced no change.
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*/
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export const updateMaster = (master, newMedia, unchangedCheck = isPlaylistUnchanged) => {
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const result = mergeOptions(master, {});
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const oldMedia = result.playlists[newMedia.id];
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if (!oldMedia) {
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return null;
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}
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if (unchangedCheck(oldMedia, newMedia)) {
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return null;
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}
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newMedia.segments = getAllSegments(newMedia);
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const mergedPlaylist = mergeOptions(oldMedia, newMedia);
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// always use the new media's preload segment
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if (mergedPlaylist.preloadSegment && !newMedia.preloadSegment) {
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delete mergedPlaylist.preloadSegment;
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}
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// if the update could overlap existing segment information, merge the two segment lists
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if (oldMedia.segments) {
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if (newMedia.skip) {
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newMedia.segments = newMedia.segments || [];
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// add back in objects for skipped segments, so that we merge
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// old properties into the new segments
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for (let i = 0; i < newMedia.skip.skippedSegments; i++) {
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newMedia.segments.unshift({skipped: true});
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}
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}
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mergedPlaylist.segments = updateSegments(
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oldMedia.segments,
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newMedia.segments,
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newMedia.mediaSequence - oldMedia.mediaSequence
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);
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}
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// resolve any segment URIs to prevent us from having to do it later
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mergedPlaylist.segments.forEach((segment) => {
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resolveSegmentUris(segment, mergedPlaylist.resolvedUri);
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});
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// TODO Right now in the playlists array there are two references to each playlist, one
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// that is referenced by index, and one by URI. The index reference may no longer be
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// necessary.
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for (let i = 0; i < result.playlists.length; i++) {
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if (result.playlists[i].id === newMedia.id) {
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result.playlists[i] = mergedPlaylist;
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}
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}
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result.playlists[newMedia.id] = mergedPlaylist;
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// URI reference added for backwards compatibility
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result.playlists[newMedia.uri] = mergedPlaylist;
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// update media group playlist references.
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forEachMediaGroup(master, (properties, mediaType, groupKey, labelKey) => {
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if (!properties.playlists) {
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return;
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}
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for (let i = 0; i < properties.playlists.length; i++) {
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if (newMedia.id === properties.playlists[i].id) {
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properties.playlists[i] = newMedia;
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}
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}
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});
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return result;
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};
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/**
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* Calculates the time to wait before refreshing a live playlist
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*
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* @param {Object} media
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* The current media
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* @param {boolean} update
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* True if there were any updates from the last refresh, false otherwise
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* @return {number}
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* The time in ms to wait before refreshing the live playlist
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*/
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export const refreshDelay = (media, update) => {
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const lastSegment = media.segments[media.segments.length - 1];
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const lastPart = lastSegment && lastSegment.parts && lastSegment.parts[lastSegment.parts.length - 1];
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const lastDuration = lastPart && lastPart.duration || lastSegment && lastSegment.duration;
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if (update && lastDuration) {
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return lastDuration * 1000;
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}
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// if the playlist is unchanged since the last reload or last segment duration
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// cannot be determined, try again after half the target duration
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return (media.partTargetDuration || media.targetDuration || 10) * 500;
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};
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/**
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* Load a playlist from a remote location
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*
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* @class PlaylistLoader
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* @extends Stream
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* @param {string|Object} src url or object of manifest
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* @param {boolean} withCredentials the withCredentials xhr option
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* @class
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*/
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export default class PlaylistLoader extends EventTarget {
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constructor(src, vhs, options = { }) {
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super();
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if (!src) {
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throw new Error('A non-empty playlist URL or object is required');
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}
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this.logger_ = logger('PlaylistLoader');
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const { withCredentials = false, handleManifestRedirects = false } = options;
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this.src = src;
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this.vhs_ = vhs;
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this.withCredentials = withCredentials;
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this.handleManifestRedirects = handleManifestRedirects;
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const vhsOptions = vhs.options_;
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this.customTagParsers = (vhsOptions && vhsOptions.customTagParsers) || [];
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this.customTagMappers = (vhsOptions && vhsOptions.customTagMappers) || [];
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this.experimentalLLHLS = (vhsOptions && vhsOptions.experimentalLLHLS) || false;
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// initialize the loader state
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this.state = 'HAVE_NOTHING';
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// live playlist staleness timeout
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this.handleMediaupdatetimeout_ = this.handleMediaupdatetimeout_.bind(this);
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this.on('mediaupdatetimeout', this.handleMediaupdatetimeout_);
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}
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handleMediaupdatetimeout_() {
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if (this.state !== 'HAVE_METADATA') {
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// only refresh the media playlist if no other activity is going on
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return;
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}
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const media = this.media();
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let uri = resolveUrl(this.master.uri, media.uri);
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if (this.experimentalLLHLS) {
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uri = addLLHLSQueryDirectives(uri, media);
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}
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this.state = 'HAVE_CURRENT_METADATA';
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this.request = this.vhs_.xhr({
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uri,
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withCredentials: this.withCredentials
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}, (error, req) => {
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// disposed
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if (!this.request) {
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return;
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}
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if (error) {
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return this.playlistRequestError(this.request, this.media(), 'HAVE_METADATA');
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}
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this.haveMetadata({
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playlistString: this.request.responseText,
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url: this.media().uri,
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id: this.media().id
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});
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});
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}
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playlistRequestError(xhr, playlist, startingState) {
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const {
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uri,
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id
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} = playlist;
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// any in-flight request is now finished
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this.request = null;
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if (startingState) {
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this.state = startingState;
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}
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this.error = {
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playlist: this.master.playlists[id],
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status: xhr.status,
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message: `HLS playlist request error at URL: ${uri}.`,
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responseText: xhr.responseText,
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code: (xhr.status >= 500) ? 4 : 2
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};
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this.trigger('error');
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}
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parseManifest_({url, manifestString}) {
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return parseManifest({
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onwarn: ({message}) => this.logger_(`m3u8-parser warn for ${url}: ${message}`),
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oninfo: ({message}) => this.logger_(`m3u8-parser info for ${url}: ${message}`),
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manifestString,
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customTagParsers: this.customTagParsers,
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customTagMappers: this.customTagMappers,
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experimentalLLHLS: this.experimentalLLHLS
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});
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}
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/**
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* Update the playlist loader's state in response to a new or updated playlist.
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*
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* @param {string} [playlistString]
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* Playlist string (if playlistObject is not provided)
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* @param {Object} [playlistObject]
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* Playlist object (if playlistString is not provided)
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* @param {string} url
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* URL of playlist
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* @param {string} id
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* ID to use for playlist
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*/
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haveMetadata({ playlistString, playlistObject, url, id }) {
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// any in-flight request is now finished
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this.request = null;
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this.state = 'HAVE_METADATA';
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const playlist = playlistObject || this.parseManifest_({
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url,
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manifestString: playlistString
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});
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playlist.lastRequest = Date.now();
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setupMediaPlaylist({
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playlist,
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uri: url,
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id
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});
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// merge this playlist into the master
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const update = updateMaster(this.master, playlist);
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this.targetDuration = playlist.partTargetDuration || playlist.targetDuration;
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if (update) {
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this.master = update;
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this.media_ = this.master.playlists[id];
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} else {
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this.trigger('playlistunchanged');
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}
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// refresh live playlists after a target duration passes
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if (!this.media().endList) {
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window.clearTimeout(this.mediaUpdateTimeout);
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this.mediaUpdateTimeout = window.setTimeout(() => {
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this.trigger('mediaupdatetimeout');
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}, refreshDelay(this.media(), !!update));
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}
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this.trigger('loadedplaylist');
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}
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/**
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* Abort any outstanding work and clean up.
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*/
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dispose() {
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this.trigger('dispose');
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this.stopRequest();
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window.clearTimeout(this.mediaUpdateTimeout);
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window.clearTimeout(this.finalRenditionTimeout);
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this.off();
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}
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stopRequest() {
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if (this.request) {
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const oldRequest = this.request;
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this.request = null;
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oldRequest.onreadystatechange = null;
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oldRequest.abort();
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}
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}
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/**
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* When called without any arguments, returns the currently
|
|
* active media playlist. When called with a single argument,
|
|
* triggers the playlist loader to asynchronously switch to the
|
|
* specified media playlist. Calling this method while the
|
|
* loader is in the HAVE_NOTHING causes an error to be emitted
|
|
* but otherwise has no effect.
|
|
*
|
|
* @param {Object=} playlist the parsed media playlist
|
|
* object to switch to
|
|
* @param {boolean=} shouldDelay whether we should delay the request by half target duration
|
|
*
|
|
* @return {Playlist} the current loaded media
|
|
*/
|
|
media(playlist, shouldDelay) {
|
|
// getter
|
|
if (!playlist) {
|
|
return this.media_;
|
|
}
|
|
|
|
// setter
|
|
if (this.state === 'HAVE_NOTHING') {
|
|
throw new Error('Cannot switch media playlist from ' + this.state);
|
|
}
|
|
|
|
// find the playlist object if the target playlist has been
|
|
// specified by URI
|
|
if (typeof playlist === 'string') {
|
|
if (!this.master.playlists[playlist]) {
|
|
throw new Error('Unknown playlist URI: ' + playlist);
|
|
}
|
|
playlist = this.master.playlists[playlist];
|
|
}
|
|
|
|
window.clearTimeout(this.finalRenditionTimeout);
|
|
|
|
if (shouldDelay) {
|
|
const delay = ((playlist.partTargetDuration || playlist.targetDuration) / 2) * 1000 || 5 * 1000;
|
|
|
|
this.finalRenditionTimeout =
|
|
window.setTimeout(this.media.bind(this, playlist, false), delay);
|
|
return;
|
|
}
|
|
|
|
const startingState = this.state;
|
|
const mediaChange = !this.media_ || playlist.id !== this.media_.id;
|
|
const masterPlaylistRef = this.master.playlists[playlist.id];
|
|
|
|
// switch to fully loaded playlists immediately
|
|
if (masterPlaylistRef && masterPlaylistRef.endList ||
|
|
// handle the case of a playlist object (e.g., if using vhs-json with a resolved
|
|
// media playlist or, for the case of demuxed audio, a resolved audio media group)
|
|
(playlist.endList && playlist.segments.length)) {
|
|
|
|
// abort outstanding playlist requests
|
|
if (this.request) {
|
|
this.request.onreadystatechange = null;
|
|
this.request.abort();
|
|
this.request = null;
|
|
}
|
|
this.state = 'HAVE_METADATA';
|
|
this.media_ = playlist;
|
|
|
|
// trigger media change if the active media has been updated
|
|
if (mediaChange) {
|
|
this.trigger('mediachanging');
|
|
|
|
if (startingState === 'HAVE_MASTER') {
|
|
// The initial playlist was a master manifest, and the first media selected was
|
|
// also provided (in the form of a resolved playlist object) as part of the
|
|
// source object (rather than just a URL). Therefore, since the media playlist
|
|
// doesn't need to be requested, loadedmetadata won't trigger as part of the
|
|
// normal flow, and needs an explicit trigger here.
|
|
this.trigger('loadedmetadata');
|
|
} else {
|
|
this.trigger('mediachange');
|
|
}
|
|
}
|
|
return;
|
|
}
|
|
|
|
// switching to the active playlist is a no-op
|
|
if (!mediaChange) {
|
|
return;
|
|
}
|
|
|
|
this.state = 'SWITCHING_MEDIA';
|
|
|
|
// there is already an outstanding playlist request
|
|
if (this.request) {
|
|
if (playlist.resolvedUri === this.request.url) {
|
|
// requesting to switch to the same playlist multiple times
|
|
// has no effect after the first
|
|
return;
|
|
}
|
|
this.request.onreadystatechange = null;
|
|
this.request.abort();
|
|
this.request = null;
|
|
}
|
|
|
|
// request the new playlist
|
|
if (this.media_) {
|
|
this.trigger('mediachanging');
|
|
}
|
|
|
|
this.request = this.vhs_.xhr({
|
|
uri: playlist.resolvedUri,
|
|
withCredentials: this.withCredentials
|
|
}, (error, req) => {
|
|
// disposed
|
|
if (!this.request) {
|
|
return;
|
|
}
|
|
|
|
playlist.lastRequest = Date.now();
|
|
|
|
playlist.resolvedUri = resolveManifestRedirect(this.handleManifestRedirects, playlist.resolvedUri, req);
|
|
|
|
if (error) {
|
|
return this.playlistRequestError(this.request, playlist, startingState);
|
|
}
|
|
|
|
this.haveMetadata({
|
|
playlistString: req.responseText,
|
|
url: playlist.uri,
|
|
id: playlist.id
|
|
});
|
|
|
|
// fire loadedmetadata the first time a media playlist is loaded
|
|
if (startingState === 'HAVE_MASTER') {
|
|
this.trigger('loadedmetadata');
|
|
} else {
|
|
this.trigger('mediachange');
|
|
}
|
|
});
|
|
}
|
|
|
|
/**
|
|
* pause loading of the playlist
|
|
*/
|
|
pause() {
|
|
this.stopRequest();
|
|
window.clearTimeout(this.mediaUpdateTimeout);
|
|
if (this.state === 'HAVE_NOTHING') {
|
|
// If we pause the loader before any data has been retrieved, its as if we never
|
|
// started, so reset to an unstarted state.
|
|
this.started = false;
|
|
}
|
|
// Need to restore state now that no activity is happening
|
|
if (this.state === 'SWITCHING_MEDIA') {
|
|
// if the loader was in the process of switching media, it should either return to
|
|
// HAVE_MASTER or HAVE_METADATA depending on if the loader has loaded a media
|
|
// playlist yet. This is determined by the existence of loader.media_
|
|
if (this.media_) {
|
|
this.state = 'HAVE_METADATA';
|
|
} else {
|
|
this.state = 'HAVE_MASTER';
|
|
}
|
|
} else if (this.state === 'HAVE_CURRENT_METADATA') {
|
|
this.state = 'HAVE_METADATA';
|
|
}
|
|
}
|
|
|
|
/**
|
|
* start loading of the playlist
|
|
*/
|
|
load(shouldDelay) {
|
|
window.clearTimeout(this.mediaUpdateTimeout);
|
|
|
|
const media = this.media();
|
|
|
|
if (shouldDelay) {
|
|
const delay = media ? ((media.partTargetDuration || media.targetDuration) / 2) * 1000 : 5 * 1000;
|
|
|
|
this.mediaUpdateTimeout = window.setTimeout(() => this.load(), delay);
|
|
return;
|
|
}
|
|
|
|
if (!this.started) {
|
|
this.start();
|
|
return;
|
|
}
|
|
|
|
if (media && !media.endList) {
|
|
this.trigger('mediaupdatetimeout');
|
|
} else {
|
|
this.trigger('loadedplaylist');
|
|
}
|
|
}
|
|
|
|
/**
|
|
* start loading of the playlist
|
|
*/
|
|
start() {
|
|
this.started = true;
|
|
|
|
if (typeof this.src === 'object') {
|
|
// in the case of an entirely constructed manifest object (meaning there's no actual
|
|
// manifest on a server), default the uri to the page's href
|
|
if (!this.src.uri) {
|
|
this.src.uri = window.location.href;
|
|
}
|
|
|
|
// resolvedUri is added on internally after the initial request. Since there's no
|
|
// request for pre-resolved manifests, add on resolvedUri here.
|
|
this.src.resolvedUri = this.src.uri;
|
|
|
|
// Since a manifest object was passed in as the source (instead of a URL), the first
|
|
// request can be skipped (since the top level of the manifest, at a minimum, is
|
|
// already available as a parsed manifest object). However, if the manifest object
|
|
// represents a master playlist, some media playlists may need to be resolved before
|
|
// the starting segment list is available. Therefore, go directly to setup of the
|
|
// initial playlist, and let the normal flow continue from there.
|
|
//
|
|
// Note that the call to setup is asynchronous, as other sections of VHS may assume
|
|
// that the first request is asynchronous.
|
|
setTimeout(() => {
|
|
this.setupInitialPlaylist(this.src);
|
|
}, 0);
|
|
return;
|
|
}
|
|
|
|
// request the specified URL
|
|
this.request = this.vhs_.xhr({
|
|
uri: this.src,
|
|
withCredentials: this.withCredentials
|
|
}, (error, req) => {
|
|
// disposed
|
|
if (!this.request) {
|
|
return;
|
|
}
|
|
|
|
// clear the loader's request reference
|
|
this.request = null;
|
|
|
|
if (error) {
|
|
this.error = {
|
|
status: req.status,
|
|
message: `HLS playlist request error at URL: ${this.src}.`,
|
|
responseText: req.responseText,
|
|
// MEDIA_ERR_NETWORK
|
|
code: 2
|
|
};
|
|
if (this.state === 'HAVE_NOTHING') {
|
|
this.started = false;
|
|
}
|
|
return this.trigger('error');
|
|
}
|
|
|
|
this.src = resolveManifestRedirect(this.handleManifestRedirects, this.src, req);
|
|
|
|
const manifest = this.parseManifest_({
|
|
manifestString: req.responseText,
|
|
url: this.src
|
|
});
|
|
|
|
this.setupInitialPlaylist(manifest);
|
|
});
|
|
}
|
|
|
|
srcUri() {
|
|
return typeof this.src === 'string' ? this.src : this.src.uri;
|
|
}
|
|
|
|
/**
|
|
* Given a manifest object that's either a master or media playlist, trigger the proper
|
|
* events and set the state of the playlist loader.
|
|
*
|
|
* If the manifest object represents a master playlist, `loadedplaylist` will be
|
|
* triggered to allow listeners to select a playlist. If none is selected, the loader
|
|
* will default to the first one in the playlists array.
|
|
*
|
|
* If the manifest object represents a media playlist, `loadedplaylist` will be
|
|
* triggered followed by `loadedmetadata`, as the only available playlist is loaded.
|
|
*
|
|
* In the case of a media playlist, a master playlist object wrapper with one playlist
|
|
* will be created so that all logic can handle playlists in the same fashion (as an
|
|
* assumed manifest object schema).
|
|
*
|
|
* @param {Object} manifest
|
|
* The parsed manifest object
|
|
*/
|
|
setupInitialPlaylist(manifest) {
|
|
this.state = 'HAVE_MASTER';
|
|
|
|
if (manifest.playlists) {
|
|
this.master = manifest;
|
|
addPropertiesToMaster(this.master, this.srcUri());
|
|
// If the initial master playlist has playlists wtih segments already resolved,
|
|
// then resolve URIs in advance, as they are usually done after a playlist request,
|
|
// which may not happen if the playlist is resolved.
|
|
manifest.playlists.forEach((playlist) => {
|
|
playlist.segments = getAllSegments(playlist);
|
|
|
|
playlist.segments.forEach((segment) => {
|
|
resolveSegmentUris(segment, playlist.resolvedUri);
|
|
});
|
|
});
|
|
this.trigger('loadedplaylist');
|
|
if (!this.request) {
|
|
// no media playlist was specifically selected so start
|
|
// from the first listed one
|
|
this.media(this.master.playlists[0]);
|
|
}
|
|
return;
|
|
}
|
|
|
|
// In order to support media playlists passed in as vhs-json, the case where the uri
|
|
// is not provided as part of the manifest should be considered, and an appropriate
|
|
// default used.
|
|
const uri = this.srcUri() || window.location.href;
|
|
|
|
this.master = masterForMedia(manifest, uri);
|
|
this.haveMetadata({
|
|
playlistObject: manifest,
|
|
url: uri,
|
|
id: this.master.playlists[0].id
|
|
});
|
|
this.trigger('loadedmetadata');
|
|
}
|
|
|
|
}
|