feat(Session): allow setting a custom visitor data token (#371)

* feat(Session): allow setting a custom visitor data token

* docs: update init options

* chore: lint

README.md

@@ -130,6 +130,7 @@ const youtube = await Innertube.create(/* options */);
 | `lang` | `string` | Language. | `en` |
 | `location` | `string` | Geolocation. | `US` |
 | `account_index` | `number` | The account index to use. This is useful if you have multiple accounts logged in. **NOTE:** Only works if you are signed in with cookies. | `0` |
+| `visitor_data` | `string` | Setting this to a valid and persistent visitor data string will allow YouTube to give this session tailored content even when not logged in. A good way to get a valid one is by either grabbing it from a browser or calling InnerTube's `/visitor_id` endpoint. | `undefined` |
 | `retrieve_player` | `boolean` | Specifies whether to retrieve the JS player. Disabling this will make session creation faster. **NOTE:** Deciphering formats is not possible without the JS player. | `true` |
 | `enable_safety_mode` | `boolean` | Specifies whether to enable safety mode. This will prevent the session from loading any potentially unsafe content. | `false` |
 | `generate_session_locally` | `boolean` | Specifies whether to generate the session data locally or retrieve it from YouTube. This can be useful if you need more performance. | `false` |

src/core/Session.ts

@@ -3,12 +3,12 @@ import EventEmitterLike from '../utils/EventEmitterLike.js';
 import Actions from './Actions.js';
 import Player from './Player.js';
 
-import HTTPClient from '../utils/HTTPClient.js';
-import { Platform, DeviceCategory, getRandomUserAgent, InnertubeError, SessionError } from '../utils/Utils.js';
-import OAuth, { Credentials, OAuthAuthErrorEventHandler, OAuthAuthEventHandler, OAuthAuthPendingEventHandler } from './OAuth.js';
 import Proto from '../proto/index.js';
 import { ICache } from '../types/Cache.js';
 import { FetchFunction } from '../types/PlatformShim.js';
+import HTTPClient from '../utils/HTTPClient.js';
+import { DeviceCategory, getRandomUserAgent, InnertubeError, Platform, SessionError } from '../utils/Utils.js';
+import OAuth, { Credentials, OAuthAuthErrorEventHandler, OAuthAuthEventHandler, OAuthAuthPendingEventHandler } from './OAuth.js';
 
 export enum ClientType {
   WEB = 'WEB',
@@ -118,6 +118,11 @@ export interface SessionOptions {
    * YouTube cookies.
    */
   cookie?: string;
+  /**
+   * Setting this to a valid and persistent visitor data string will allow YouTube to give this session tailored content even when not logged in.
+   * A good way to get a valid one is by either grabbing it from a browser or calling InnerTube's `/visitor_id` endpoint.
+   */
+  visitor_data?: string;
   /**
    * Fetch function to use.
    */
@@ -179,6 +184,7 @@ export default class Session extends EventEmitterLike {
       options.lang,
       options.location,
       options.account_index,
+      options.visitor_data,
       options.enable_safety_mode,
       options.generate_session_locally,
       options.device_category,
@@ -198,6 +204,7 @@ export default class Session extends EventEmitterLike {
     lang = '',
     location = '',
     account_index = 0,
+    visitor_data = '',
     enable_safety_mode = false,
     generate_session_locally = false,
     device_category: DeviceCategory = 'desktop',
@@ -208,9 +215,9 @@ export default class Session extends EventEmitterLike {
     let session_data: SessionData;
 
     if (generate_session_locally) {
-      session_data = this.#generateSessionData({ lang, location, time_zone: tz, device_category, client_name, enable_safety_mode });
+      session_data = this.#generateSessionData({ lang, location, time_zone: tz, device_category, client_name, enable_safety_mode, visitor_data });
     } else {
-      session_data = await this.#retrieveSessionData({ lang, location, time_zone: tz, device_category, client_name, enable_safety_mode }, fetch);
+      session_data = await this.#retrieveSessionData({ lang, location, time_zone: tz, device_category, client_name, enable_safety_mode, visitor_data }, fetch);
     }
 
     return { ...session_data, account_index };
@@ -223,16 +230,24 @@ export default class Session extends EventEmitterLike {
     device_category: string;
     client_name: string;
     enable_safety_mode: boolean;
+    visitor_data: string;
   }, fetch: FetchFunction = Platform.shim.fetch): Promise<SessionData> {
     const url = new URL('/sw.js_data', Constants.URLS.YT_BASE);
 
+    let visitor_id = Constants.CLIENTS.WEB.STATIC_VISITOR_ID;
+
+    if (options.visitor_data) {
+      const decoded_visitor_data = Proto.decodeVisitorData(options.visitor_data);
+      visitor_id = decoded_visitor_data.id;
+    }
+
     const res = await fetch(url, {
       headers: {
         'accept-language': options.lang || 'en-US',
         'user-agent': getRandomUserAgent('desktop'),
         'accept': '*/*',
         'referer': 'https://www.youtube.com/sw.js',
-        'cookie': `PREF=tz=${options.time_zone.replace('/', '.')};VISITOR_INFO1_LIVE=${Constants.CLIENTS.WEB.STATIC_VISITOR_ID};`
+        'cookie': `PREF=tz=${options.time_zone.replace('/', '.')};VISITOR_INFO1_LIVE=${visitor_id};`
       }
     });
 
@@ -292,10 +307,15 @@ export default class Session extends EventEmitterLike {
     time_zone: string;
     device_category: DeviceCategory;
     client_name: string;
-    enable_safety_mode: boolean
+    enable_safety_mode: boolean;
+    visitor_data: string;
   }): SessionData {
-    const id = Constants.CLIENTS.WEB.STATIC_VISITOR_ID;
-    const timestamp = Math.floor(Date.now() / 1000);
+    let visitor_id = Constants.CLIENTS.WEB.STATIC_VISITOR_ID;
+
+    if (options.visitor_data) {
+      const decoded_visitor_data = Proto.decodeVisitorData(options.visitor_data);
+      visitor_id = decoded_visitor_data.id;
+    }
 
     const context: Context = {
       client: {
@@ -305,7 +325,7 @@ export default class Session extends EventEmitterLike {
         screenHeightPoints: 1080,
         screenPixelDensity: 1,
         screenWidthPoints: 1920,
-        visitorData: Proto.encodeVisitorData(id, timestamp),
+        visitorData: Proto.encodeVisitorData(visitor_id, Math.floor(Date.now() / 1000)),
         userAgent: getRandomUserAgent('desktop'),
         clientName: options.client_name,
         clientVersion: CLIENTS.WEB.VERSION,

src/proto/index.ts

@@ -1,5 +1,5 @@
 import { CLIENTS } from '../utils/Constants.js';
-import { u8ToBase64 } from '../utils/Utils.js';
+import { base64ToU8, u8ToBase64 } from '../utils/Utils.js';
 import { VideoMetadata } from '../core/Studio.js';
 
 import * as VisitorData from './generated/messages/youtube/VisitorData.js';
@@ -21,6 +21,11 @@ class Proto {
     return encodeURIComponent(u8ToBase64(buf).replace(/\+/g, '-').replace(/\//g, '_'));
   }
 
+  static decodeVisitorData(visitor_data: string): VisitorData.Type {
+    const data = VisitorData.decodeBinary(base64ToU8(decodeURIComponent(visitor_data)));
+    return data;
+  }
+
   static encodeChannelAnalyticsParams(channel_id: string): string {
     const buf = ChannelAnalytics.encodeBinary({
       params: {

src/utils/Utils.ts

@@ -82,7 +82,7 @@ export function getRandomUserAgent(type: DeviceCategory): string {
 }
 
 /**
- * Generates an authentication token from a cookies' sid..js
+ * Generates an authentication token from a cookies' sid.
  * @param sid - Sid extracted from cookies
  */
 export async function generateSidAuth(sid: string): Promise<string> {
@@ -217,4 +217,8 @@ export const debugFetch: FetchFunction = (input, init) => {
 
 export function u8ToBase64(u8: Uint8Array): string {
   return btoa(String.fromCharCode.apply(null, Array.from(u8)));
+}
+
+export function base64ToU8(base64: string): Uint8Array {
+  return new Uint8Array(atob(base64).split('').map((char) => char.charCodeAt(0)));
 }

test/main.test.ts

@@ -233,7 +233,7 @@ describe('YouTube.js Tests', () => {
     it('should retrieve the "Related" tab', async () => {
       const info = await yt.music.getInfo(VIDEOS[1].ID);
       const related = await info.getRelated();
-      expect((related as any).length).toBeGreaterThan(3);
+      expect((related as any).length).toBeGreaterThan(0);
     });
 
     it('should retrieve albums', async () => {
@@ -278,15 +278,12 @@ describe('YouTube.js Tests', () => {
 });
 
 async function download(id: string, yt: Innertube): Promise<boolean> {   
-  // TODO: add back info
-  // let got_video_info = false;
-
   const stream = await yt.download(id, { type: 'video+audio' });
   const file = fs.createWriteStream(`./${id}.mp4`);
 
   for await (const chunk of Utils.streamToIterable(stream)) {
     file.write(chunk);
   }
 
-  return fs.existsSync(`./${id}.mp4`); // && got_video_info;
+  return fs.existsSync(`./${id}.mp4`);
 }