Add variable user agents for fetch

src/constants.ts

@@ -1,7 +1,3 @@
-/* We keep this value up-to-date for making our requests to Twitter as
-   indistinguishable from normal user traffic as possible. */
-const fakeChromeVersion = '105';
-
 export const Constants = {
   /* These constants are populated by variables in .env, then set by Webpack */
   BRANDING_NAME: BRANDING_NAME,
@@ -38,12 +34,10 @@ export const Constants = {
     'simple_quoted_tweet=true'
   ].join('&'),
   BASE_HEADERS: {
-    'sec-ch-ua': `".Not/A)Brand";v="99", "Google Chrome";v="${fakeChromeVersion}", "Chromium";v="${fakeChromeVersion}"`,
     'DNT': `1`,
     'x-twitter-client-language': `en`,
     'sec-ch-ua-mobile': `?0`,
     'content-type': `application/x-www-form-urlencoded`,
-    'User-Agent': `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/${fakeChromeVersion}.0.0.0 Safari/537.36`,
     'x-twitter-active-user': `yes`,
     'sec-ch-ua-platform': `"Windows"`,
     'Accept': `*/*`,

src/fetch.ts

@@ -1,4 +1,5 @@
 import { Constants } from './constants';
+import { generateUserAgent } from './helpers/useragent';
 
 const API_ATTEMPTS = 16;
 
@@ -10,8 +11,13 @@ export const twitterFetch = async (
   let apiAttempts = 0;
   let newTokenGenerated = false;
 
+  const [userAgent, secChUa] = generateUserAgent();
+  console.log('Hello, I am', userAgent);
+
   const tokenHeaders: { [header: string]: string } = {
-    Authorization: Constants.GUEST_BEARER_TOKEN,
+    'Authorization': Constants.GUEST_BEARER_TOKEN,
+    'User-Agent': userAgent,
+    'sec-ch-ua': secChUa,
     ...Constants.BASE_HEADERS
   };
 

src/helpers/author.ts

@@ -1,4 +1,4 @@
-import { formatNumber } from "./utils";
+import { formatNumber } from './utils';
 
 /* The embed "author" text we populate with replies, retweets, and likes unless it's a video */
 export const getAuthorText = (tweet: APITweet): string | null => {

src/helpers/useragent.ts

@@ -0,0 +1,50 @@
+/* We keep this value up-to-date for making our requests to Twitter as
+   indistinguishable from normal user traffic as possible. */
+const fakeChromeVersion = 109;
+const platformWindows = 'Windows NT 10.0; Win64; x64';
+const platformMac = 'Macintosh; Intel Mac OS X 10_15_7';
+const platformLinux = 'X11; Linux x86_64';
+const platformAndroid = 'Linux; Android 13; Pixel 7';
+const chromeUA = `Mozilla/5.0 ({platform}) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/{version}.0.0.0 Safari/537.36`;
+const edgeUA = `Mozilla/5.0 ({platform}) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/{version}.0.0.0 Safari/537.36 Edg/{version}.0.0.0`;
+const chromeMobileUA = `Mozilla/5.0 ({platform}) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/{version}.0.0.0 Mobile Safari/537.36`;
+const edgeMobileUA = `Mozilla/5.0 ({platform}) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/{version}.0.0.0 Mobile Safari/537.36 Edg/{version}.0.0.0`;
+
+enum Platforms {
+  Windows,
+  Mac,
+  Linux,
+  Android
+}
+
+/* Return a random version of Chrome between current and 2 previous versions (i.e. For 109, also return 108 or 107) */
+const getRandomVersion = (): number => fakeChromeVersion - Math.floor(Math.random() * 3);
+
+export const generateUserAgent = (): [string, string] => {
+  const platform = Math.floor(Math.random() * 4);
+  const isEdge = Math.random() > 0.5;
+  const version = getRandomVersion();
+
+  let userAgent = isEdge ? edgeUA : chromeUA;
+  userAgent = userAgent.format({ version: String(version) });
+  const secChUaChrome = `".Not/A)Brand";v="99", "Google Chrome";v="{version}", "Chromium";v="{version}"`;
+  const secChUaEdge = `".Not/A)Brand";v="99", "Microsoft Edge";v="{version}", "Chromium";v="{version}"`;
+  const secChUa = (isEdge ? secChUaEdge : secChUaChrome).format({
+    version: String(version)
+  });
+
+  switch (platform) {
+    case Platforms.Mac:
+      return [userAgent.format({ platform: platformMac }), secChUa];
+    case Platforms.Linux:
+      return [userAgent.format({ platform: platformLinux }), secChUa];
+    case Platforms.Android:
+      userAgent = isEdge ? edgeMobileUA : chromeMobileUA;
+      return [
+        userAgent.format({ platform: platformAndroid, version: String(version) }),
+        secChUa
+      ];
+    default:
+      return [userAgent.format({ platform: platformWindows }), secChUa];
+  }
+};

src/helpers/utils.ts

@@ -17,4 +17,4 @@ export const unescapeText = (text: string) => {
 
 const numberFormat = new Intl.NumberFormat('en-US');
 
-export const formatNumber = (num: number) => numberFormat.format(num)
+export const formatNumber = (num: number) => numberFormat.format(num);