perf: make additional dash and m3u8 format requests faster

lib/info.js

@@ -191,12 +191,11 @@ exports.getFullInfo = async(id, options) => {
       info.player_response.streamingData.dashManifestUrl ||
       info.player_response.streamingData.hlsManifestUrl
     );
+  let funcs = [];
   if (info.formats.length) {
-    const html5playerfile = urllib.resolve(VIDEO_URL, info.html5player);
-    let tokens = await sig.getTokens(html5playerfile, options);
-    sig.decipherFormats(info.formats, tokens, options.debug);
+    const html5player = urllib.resolve(VIDEO_URL, info.html5player);
+    funcs.push(sig.decipherFormats(info.formats, html5player, options));
   }
-  let funcs = [];
   if (hasManifest && info.player_response.streamingData.dashManifestUrl) {
     let url = info.player_response.streamingData.dashManifestUrl;
     funcs.push(getDashManifest(url, options));
@@ -207,30 +206,14 @@ exports.getFullInfo = async(id, options) => {
   }
 
   let results = await Promise.all(funcs);
-  if (results[0]) { mergeFormats(info, results[0]); }
-  if (results[1]) { mergeFormats(info, results[1]); }
-
+  info.formats = Object.values(Object.assign({}, ...results));
   info.formats = info.formats.map(util.addFormatMeta);
   info.formats.sort(util.sortFormats);
   info.full = true;
   return info;
 };
 
 
-/**
- * Merges formats from DASH or M3U8 with formats from video info page.
- *
- * @param {Object} info
- * @param {Object} formatsMap
- */
-const mergeFormats = (info, formatsMap) => {
-  info.formats.forEach(f => {
-    formatsMap[f.itag] = formatsMap[f.itag] || f;
-  });
-  info.formats = Object.values(formatsMap);
-};
-
-
 /**
  * Gets additional DASH formats.
  *

lib/sig.js

@@ -24,7 +24,6 @@ exports.getTokens = async(html5playerfile, options) => {
     if (!tokens || !tokens.length) {
       throw Error('Could not extract signature deciphering actions');
     }
-
     exports.cache.set(html5playerfile, tokens);
     return tokens;
   }
@@ -245,10 +244,11 @@ exports.setDownloadURL = (format, sig, debug) => {
  * Applies `sig.decipher()` to all format URL's.
  *
  * @param {Array.<Object>} formats
- * @param {Array.<string>} tokens
- * @param {boolean} debug
+ * @param {string} html5player
+ * @param {Object} options
  */
-exports.decipherFormats = (formats, tokens, debug) => {
+exports.decipherFormats = async(formats, html5player, options) => {
+  let tokens = await exports.getTokens(html5player, options);
   formats.forEach(format => {
     let cipher = format.signatureCipher || format.cipher;
     if (cipher) {
@@ -257,6 +257,7 @@ exports.decipherFormats = (formats, tokens, debug) => {
       delete format.cipher;
     }
     const sig = tokens && format.s ? exports.decipher(tokens, format.s) : null;
-    exports.setDownloadURL(format, sig, debug);
+    exports.setDownloadURL(format, sig, options.debug);
   });
+  return formats;
 };