const qs = require('querystring'); const url = require('url'); const FORMATS = require('./formats'); // Use these to help sort formats, higher is better. const audioEncodingRanks = { mp3: 1, vorbis: 2, aac: 3, opus: 4, flac: 5, }; const videoEncodingRanks = { 'Sorenson H.283': 1, 'MPEG-4 Visual': 2, 'VP8': 3, 'VP9': 4, 'H.264': 5, }; /** * Sort formats from highest quality to lowest. * By resolution, then video bitrate, then audio bitrate. * * @param {Object} a * @param {Object} b */ exports.sortFormats = (a, b) => { const ares = a.resolution ? parseInt(a.resolution.slice(0, -1), 10) : 0; const bres = b.resolution ? parseInt(b.resolution.slice(0, -1), 10) : 0; const afeats = ~~!!ares * 2 + ~~!!a.audioBitrate; const bfeats = ~~!!bres * 2 + ~~!!b.audioBitrate; const getBitrate = (c) => { if (c.bitrate) { let s = c.bitrate.split('-'); return parseFloat(s[s.length - 1], 10); } else { return 0; } }; const audioScore = (c) => { const abitrate = c.audioBitrate || 0; const aenc = audioEncodingRanks[c.audioEncoding] || 0; return abitrate + aenc / 10; }; if (afeats === bfeats) { if (ares === bres) { let avbitrate = getBitrate(a); let bvbitrate = getBitrate(b); if (avbitrate === bvbitrate) { let aascore = audioScore(a); let bascore = audioScore(b); if (aascore === bascore) { let avenc = videoEncodingRanks[a.encoding] || 0; let bvenc = videoEncodingRanks[b.encoding] || 0; return bvenc - avenc; } else { return bascore - aascore; } } else { return bvbitrate - avbitrate; } } else { return bres - ares; } } else { return bfeats - afeats; } }; /** * Choose a format depending on the given options. * * @param {Array.} formats * @param {Object} options * @return {Object|Error} */ exports.chooseFormat = (formats, options) => { if (typeof options.format === 'object') { return options.format; } if (options.filter) { formats = exports.filterFormats(formats, options.filter); if (formats.length === 0) { return Error('No formats found with custom filter'); } } let format; const quality = options.quality || 'highest'; const getBitrate = (f) => { let s = f.bitrate.split('-'); return parseFloat(s[s.length - 1], 10); }; switch (quality) { case 'highest': format = formats[0]; break; case 'lowest': format = formats[formats.length - 1]; break; case 'highestaudio': formats = exports.filterFormats(formats, 'audio'); format = null; for (let f of formats) { if (!format || f.audioBitrate > format.audioBitrate || (f.audioBitrate === format.audioBitrate && format.encoding && !f.encoding)) format = f; } break; case 'lowestaudio': formats = exports.filterFormats(formats, 'audio') format = null; for (let f of formats) { if (!format || f.audioBitrate < format.audioBitrate || (f.audioBitrate === format.audioBitrate && format.encoding && !f.encoding)) format = f; } break; case 'highestvideo': formats = exports.filterFormats(formats, 'video'); format = null; for (let f of formats) { if (!format || getBitrate(f) > getBitrate(format) || (getBitrate(f) === getBitrate(format) && format.audioEncoding && !f.audioEncoding)) format = f; } break; case 'lowestvideo': formats = exports.filterFormats(formats, 'video') format = null; for (let f of formats) { if (!format || getBitrate(f) < getBitrate(format) || (getBitrate(f) === getBitrate(format) && format.audioEncoding && !f.audioEncoding)) format = f; } break; default: { let getFormat = (itag) => { return formats.find((format) => format.itag === '' + itag); }; if (Array.isArray(quality)) { quality.find((q) => format = getFormat(q)); } else { format = getFormat(quality); } } } if (!format) { return Error('No such format found: ' + quality); } return format; }; /** * @param {Array.} formats * @param {Function} filter * @return {Array.} */ exports.filterFormats = (formats, filter) => { let fn; switch (filter) { case 'audioandvideo': fn = (format) => format.bitrate && format.audioBitrate; break; case 'video': fn = (format) => format.bitrate; break; case 'videoonly': fn = (format) => format.bitrate && !format.audioBitrate; break; case 'audio': fn = (format) => format.audioBitrate; break; case 'audioonly': fn = (format) => !format.bitrate && format.audioBitrate; break; default: if (typeof filter === 'function') { fn = filter; } else { throw TypeError(`Given filter (${filter}) is not supported`); } } return formats.filter(fn); }; /** * String#indexOf() that supports regex too. * * @param {string} haystack * @param {string|RegExp} needle * @return {number} */ const indexOf = (haystack, needle) => { return needle instanceof RegExp ? haystack.search(needle) : haystack.indexOf(needle); }; /** * Extract string inbetween another. * * @param {string} haystack * @param {string} left * @param {string} right * @return {string} */ exports.between = (haystack, left, right) => { let pos = indexOf(haystack, left); if (pos === -1) { return ''; } haystack = haystack.slice(pos + left.length); pos = indexOf(haystack, right); if (pos === -1) { return ''; } haystack = haystack.slice(0, pos); return haystack; }; /** * Get video ID. * * There are a few type of video URL formats. * - https://www.youtube.com/watch?v=VIDEO_ID * - https://m.youtube.com/watch?v=VIDEO_ID * - https://youtu.be/VIDEO_ID * - https://www.youtube.com/v/VIDEO_ID * - https://www.youtube.com/embed/VIDEO_ID * - https://music.youtube.com/watch?v=VIDEO_ID * - https://gaming.youtube.com/watch?v=VIDEO_ID * * @param {string} link * @return {string|Error} */ const validQueryDomains = new Set([ 'youtube.com', 'www.youtube.com', 'm.youtube.com', 'music.youtube.com', 'gaming.youtube.com', ]); const validPathDomains = new Set([ 'youtu.be', 'youtube.com', 'www.youtube.com', ]); exports.getURLVideoID = (link) => { const parsed = url.parse(link, true); let id = parsed.query.v; if (validPathDomains.has(parsed.hostname) && !id) { const paths = parsed.pathname.split('/'); id = paths[paths.length - 1]; } else if (parsed.hostname && !validQueryDomains.has(parsed.hostname)) { return Error('Not a YouTube domain'); } if (!id) { return Error('No video id found: ' + link); } id = id.substring(0, 11); if (!exports.validateID(id)) { return TypeError(`Video id (${id}) does not match expected ` + `format (${idRegex.toString()})`); } return id; }; /** * Gets video ID either from a url or by checking if the given string * matches the video ID format. * * @param {string} str * @return {string|Error} */ exports.getVideoID = (str) => { if (exports.validateID(str)) { return str; } else { return exports.getURLVideoID(str); } }; /** * Returns true if given id satifies YouTube's id format. * * @param {string} id * @return {boolean} */ const idRegex = /^[a-zA-Z0-9-_]{11}$/; exports.validateID = (id) => { return idRegex.test(id); }; /** * Checks wether the input string includes a valid id. * * @param {string} string * @return {boolean} */ exports.validateURL = (string) => { return !(exports.getURLVideoID(string) instanceof Error); }; /** * @param {Object} info * @return {Array.} */ exports.parseFormats = (info) => { let formats = []; if (info.url_encoded_fmt_stream_map) { formats = formats .concat(info.url_encoded_fmt_stream_map.split(',')); } if (info.adaptive_fmts) { formats = formats.concat(info.adaptive_fmts.split(',')); } formats = formats.map((format) => qs.parse(format)); delete info.url_encoded_fmt_stream_map; delete info.adaptive_fmts; return formats; }; /** * @param {Object} format */ exports.addFormatMeta = (format) => { const meta = FORMATS[format.itag]; for (let key in meta) { format[key] = meta[key]; } format.live = /\/source\/yt_live_broadcast\//.test(format.url); format.isHLS = /\/manifest\/hls_(variant|playlist)\//.test(format.url); format.isDashMPD = /\/manifest\/dash\//.test(format.url); }; /** * Get only the string from an HTML string. * * @param {string} html * @return {string} */ exports.stripHTML = (html) => { return html .replace(/\n/g, ' ') .replace(/\s*<\s*br\s*\/?\s*>\s*/gi, '\n') .replace(/<\s*\/\s*p\s*>\s*<\s*p[^>]*>/gi, '\n') .replace(/<.*?>/gi, '') .trim(); }; /** * @param {Array.} funcs * @param {Function(!Error, Array.)} callback */ exports.parallel = (funcs, callback) => { let funcsDone = 0; let errGiven = false; let results = []; const len = funcs.length; const checkDone = (index, err, result) => { if (errGiven) { return; } if (err) { errGiven = true; callback(err); return; } results[index] = result; if (++funcsDone === len) { callback(null, results); } }; if (len > 0) { funcs.forEach((f, i) => { f(checkDone.bind(null, i)); }); } else { callback(null, results); } };