parser.js
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'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
var _extends = Object.assign || function (target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i]; for (var key in source) { if (Object.prototype.hasOwnProperty.call(source, key)) { target[key] = source[key]; } } } return target; };
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
var _stream = require('./stream');
var _stream2 = _interopRequireDefault(_stream);
var _lineStream = require('./line-stream');
var _lineStream2 = _interopRequireDefault(_lineStream);
var _parseStream = require('./parse-stream');
var _parseStream2 = _interopRequireDefault(_parseStream);
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { 'default': obj }; }
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }
function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; } /**
* @file m3u8/parser.js
*/
/**
* A parser for M3U8 files. The current interpretation of the input is
* exposed as a property `manifest` on parser objects. It's just two lines to
* create and parse a manifest once you have the contents available as a string:
*
* ```js
* var parser = new m3u8.Parser();
* parser.push(xhr.responseText);
* ```
*
* New input can later be applied to update the manifest object by calling
* `push` again.
*
* The parser attempts to create a usable manifest object even if the
* underlying input is somewhat nonsensical. It emits `info` and `warning`
* events during the parse if it encounters input that seems invalid or
* requires some property of the manifest object to be defaulted.
*
* @class Parser
* @extends Stream
*/
var Parser = function (_Stream) {
_inherits(Parser, _Stream);
function Parser() {
_classCallCheck(this, Parser);
var _this = _possibleConstructorReturn(this, (Parser.__proto__ || Object.getPrototypeOf(Parser)).call(this));
_this.lineStream = new _lineStream2['default']();
_this.parseStream = new _parseStream2['default']();
_this.lineStream.pipe(_this.parseStream);
/* eslint-disable consistent-this */
var self = _this;
/* eslint-enable consistent-this */
var uris = [];
var currentUri = {};
// if specified, the active EXT-X-MAP definition
var currentMap = void 0;
// if specified, the active decryption key
var _key = void 0;
var noop = function noop() {};
var defaultMediaGroups = {
'AUDIO': {},
'VIDEO': {},
'CLOSED-CAPTIONS': {},
'SUBTITLES': {}
};
// group segments into numbered timelines delineated by discontinuities
var currentTimeline = 0;
// the manifest is empty until the parse stream begins delivering data
_this.manifest = {
allowCache: true,
discontinuityStarts: [],
segments: []
};
// update the manifest with the m3u8 entry from the parse stream
_this.parseStream.on('data', function (entry) {
var mediaGroup = void 0;
var rendition = void 0;
({
tag: function tag() {
// switch based on the tag type
(({
'allow-cache': function allowCache() {
this.manifest.allowCache = entry.allowed;
if (!('allowed' in entry)) {
this.trigger('info', {
message: 'defaulting allowCache to YES'
});
this.manifest.allowCache = true;
}
},
byterange: function byterange() {
var byterange = {};
if ('length' in entry) {
currentUri.byterange = byterange;
byterange.length = entry.length;
if (!('offset' in entry)) {
this.trigger('info', {
message: 'defaulting offset to zero'
});
entry.offset = 0;
}
}
if ('offset' in entry) {
currentUri.byterange = byterange;
byterange.offset = entry.offset;
}
},
endlist: function endlist() {
this.manifest.endList = true;
},
inf: function inf() {
if (!('mediaSequence' in this.manifest)) {
this.manifest.mediaSequence = 0;
this.trigger('info', {
message: 'defaulting media sequence to zero'
});
}
if (!('discontinuitySequence' in this.manifest)) {
this.manifest.discontinuitySequence = 0;
this.trigger('info', {
message: 'defaulting discontinuity sequence to zero'
});
}
if (entry.duration > 0) {
currentUri.duration = entry.duration;
}
if (entry.duration === 0) {
currentUri.duration = 0.01;
this.trigger('info', {
message: 'updating zero segment duration to a small value'
});
}
this.manifest.segments = uris;
},
key: function key() {
if (!entry.attributes) {
this.trigger('warn', {
message: 'ignoring key declaration without attribute list'
});
return;
}
// clear the active encryption key
if (entry.attributes.METHOD === 'NONE') {
_key = null;
return;
}
if (!entry.attributes.URI) {
this.trigger('warn', {
message: 'ignoring key declaration without URI'
});
return;
}
if (!entry.attributes.METHOD) {
this.trigger('warn', {
message: 'defaulting key method to AES-128'
});
}
// setup an encryption key for upcoming segments
_key = {
method: entry.attributes.METHOD || 'AES-128',
uri: entry.attributes.URI
};
if (typeof entry.attributes.IV !== 'undefined') {
_key.iv = entry.attributes.IV;
}
},
'media-sequence': function mediaSequence() {
if (!isFinite(entry.number)) {
this.trigger('warn', {
message: 'ignoring invalid media sequence: ' + entry.number
});
return;
}
this.manifest.mediaSequence = entry.number;
},
'discontinuity-sequence': function discontinuitySequence() {
if (!isFinite(entry.number)) {
this.trigger('warn', {
message: 'ignoring invalid discontinuity sequence: ' + entry.number
});
return;
}
this.manifest.discontinuitySequence = entry.number;
currentTimeline = entry.number;
},
'playlist-type': function playlistType() {
if (!/VOD|EVENT/.test(entry.playlistType)) {
this.trigger('warn', {
message: 'ignoring unknown playlist type: ' + entry.playlist
});
return;
}
this.manifest.playlistType = entry.playlistType;
},
map: function map() {
currentMap = {};
if (entry.uri) {
currentMap.uri = entry.uri;
}
if (entry.byterange) {
currentMap.byterange = entry.byterange;
}
},
'stream-inf': function streamInf() {
this.manifest.playlists = uris;
this.manifest.mediaGroups = this.manifest.mediaGroups || defaultMediaGroups;
if (!entry.attributes) {
this.trigger('warn', {
message: 'ignoring empty stream-inf attributes'
});
return;
}
if (!currentUri.attributes) {
currentUri.attributes = {};
}
_extends(currentUri.attributes, entry.attributes);
},
media: function media() {
this.manifest.mediaGroups = this.manifest.mediaGroups || defaultMediaGroups;
if (!(entry.attributes && entry.attributes.TYPE && entry.attributes['GROUP-ID'] && entry.attributes.NAME)) {
this.trigger('warn', {
message: 'ignoring incomplete or missing media group'
});
return;
}
// find the media group, creating defaults as necessary
var mediaGroupType = this.manifest.mediaGroups[entry.attributes.TYPE];
mediaGroupType[entry.attributes['GROUP-ID']] = mediaGroupType[entry.attributes['GROUP-ID']] || {};
mediaGroup = mediaGroupType[entry.attributes['GROUP-ID']];
// collect the rendition metadata
rendition = {
'default': /yes/i.test(entry.attributes.DEFAULT)
};
if (rendition['default']) {
rendition.autoselect = true;
} else {
rendition.autoselect = /yes/i.test(entry.attributes.AUTOSELECT);
}
if (entry.attributes.LANGUAGE) {
rendition.language = entry.attributes.LANGUAGE;
}
if (entry.attributes.URI) {
rendition.uri = entry.attributes.URI;
}
if (entry.attributes['INSTREAM-ID']) {
rendition.instreamId = entry.attributes['INSTREAM-ID'];
}
if (entry.attributes.CHARACTERISTICS) {
rendition.characteristics = entry.attributes.CHARACTERISTICS;
}
if (entry.attributes.FORCED) {
rendition.forced = /yes/i.test(entry.attributes.FORCED);
}
// insert the new rendition
mediaGroup[entry.attributes.NAME] = rendition;
},
discontinuity: function discontinuity() {
currentTimeline += 1;
currentUri.discontinuity = true;
this.manifest.discontinuityStarts.push(uris.length);
},
'program-date-time': function programDateTime() {
this.manifest.dateTimeString = entry.dateTimeString;
this.manifest.dateTimeObject = entry.dateTimeObject;
},
targetduration: function targetduration() {
if (!isFinite(entry.duration) || entry.duration < 0) {
this.trigger('warn', {
message: 'ignoring invalid target duration: ' + entry.duration
});
return;
}
this.manifest.targetDuration = entry.duration;
},
totalduration: function totalduration() {
if (!isFinite(entry.duration) || entry.duration < 0) {
this.trigger('warn', {
message: 'ignoring invalid total duration: ' + entry.duration
});
return;
}
this.manifest.totalDuration = entry.duration;
},
'cue-out': function cueOut() {
currentUri.cueOut = entry.data;
},
'cue-out-cont': function cueOutCont() {
currentUri.cueOutCont = entry.data;
},
'cue-in': function cueIn() {
currentUri.cueIn = entry.data;
}
})[entry.tagType] || noop).call(self);
},
uri: function uri() {
currentUri.uri = entry.uri;
uris.push(currentUri);
// if no explicit duration was declared, use the target duration
if (this.manifest.targetDuration && !('duration' in currentUri)) {
this.trigger('warn', {
message: 'defaulting segment duration to the target duration'
});
currentUri.duration = this.manifest.targetDuration;
}
// annotate with encryption information, if necessary
if (_key) {
currentUri.key = _key;
}
currentUri.timeline = currentTimeline;
// annotate with initialization segment information, if necessary
if (currentMap) {
currentUri.map = currentMap;
}
// prepare for the next URI
currentUri = {};
},
comment: function comment() {
// comments are not important for playback
}
})[entry.type].call(self);
});
return _this;
}
/**
* Parse the input string and update the manifest object.
*
* @param {String} chunk a potentially incomplete portion of the manifest
*/
_createClass(Parser, [{
key: 'push',
value: function push(chunk) {
this.lineStream.push(chunk);
}
/**
* Flush any remaining input. This can be handy if the last line of an M3U8
* manifest did not contain a trailing newline but the file has been
* completely received.
*/
}, {
key: 'end',
value: function end() {
// flush any buffered input
this.lineStream.push('\n');
}
}]);
return Parser;
}(_stream2['default']);
exports['default'] = Parser;