AG-41048 Fix 'trusted-set-cookie-reload' — prevent infinite reload for constantly changing values. #489

Squashed commit of the following:

commit 9963438
Author: Adam Wróblewski <[email protected]>
Date:   Wed Jun 18 12:36:37 2025 +0200

    Update comment

commit c2a9eab
Author: Adam Wróblewski <[email protected]>
Date:   Wed Jun 18 10:18:50 2025 +0200

    Move timeKeywords to isCookieSetWithValue

commit e44de75
Author: Adam Wróblewski <[email protected]>
Date:   Tue Jun 17 13:10:34 2025 +0200

    Add comments
    Change variable name to UPPER_SNAKE_CASE format

commit 0725ec3
Author: Adam Wróblewski <[email protected]>
Date:   Wed Jun 11 14:11:21 2025 +0200

    Fix 'trusted-set-cookie-reload' — prevent infinite reload for constantly changing values

Author: AdamWr

CHANGELOG.md

@@ -10,6 +10,15 @@ The format is based on [Keep a Changelog], and this project adheres to [Semantic
 <!-- TODO: change `@added unknown` tag due to the actual version -->
 <!--       during new scriptlets or redirects releasing -->
 
+## [Unreleased]
+
+### Fixed
+
+- `trusted-set-cookie-reload` scriptlet infinite page reloading when cookie with time keyword is used [#489].
+
+[Unreleased]: https://github.com/AdguardTeam/Scriptlets/compare/v2.2.7...HEAD
+[#489]: https://github.com/AdguardTeam/Scriptlets/issues/489
+
 <!-- v2.2.6 is the same as v2.2.7 -->
 ## [v2.2.7] - 2025-06-04
 

src/helpers/cookie-utils.ts

@@ -201,7 +201,11 @@ export const parseCookieString = (cookieString: string): CookieData => {
  * @param value value argument of *set-cookie-* scriptlets
  * @returns if cookie is already set
  */
-export const isCookieSetWithValue = (cookieString: string, name: string, value: string): boolean => {
+export const isCookieSetWithValue = (
+    cookieString: string,
+    name: string,
+    value: string,
+): boolean => {
     return cookieString.split(';')
         .some((cookieStr) => {
             const pos = cookieStr.indexOf('=');
@@ -211,6 +215,30 @@ export const isCookieSetWithValue = (cookieString: string, name: string, value:
             const cookieName = cookieStr.slice(0, pos).trim();
             const cookieValue = cookieStr.slice(pos + 1).trim();
 
+            // If required, remember to sync new time keywords with the "parseKeywordValue" function
+            const timeKeywords = new Set([
+                '$now$',
+                '$currentDate$',
+                '$currentISODate$',
+            ]);
+            const isValueTimeKeyword = timeKeywords.has(value);
+
+            // Prevent webpage reloading when cookie value is a time keyword
+            // https://github.com/AdguardTeam/Scriptlets/issues/489
+            if (isValueTimeKeyword) {
+                // The time after which the website will reload (1 day)
+                const ONE_DAY_MS = 24 * 60 * 60 * 1000;
+                const now = Date.now();
+                // Convert cookie value to milliseconds
+                const cookieValueMs = /^\d+$/.test(cookieValue)
+                    ? parseInt(cookieValue, 10)
+                    : new Date(cookieValue).getTime();
+
+                // If cookie value is greater than now minus one day, return true,
+                // otherwise return false and new cookie should be set
+                return name === cookieName && cookieValueMs > now - ONE_DAY_MS;
+            }
+
             return name === cookieName && value === cookieValue;
         });
 };

src/helpers/parse-keyword-value.ts

@@ -11,6 +11,8 @@
  */
 export const parseKeywordValue = (rawValue: string): string => {
     // !IMPORTANT: Do not move constants outside of this function
+    // Remember to add new keywords to "isCookieSetWithValue" function in "cookie-utils", if required
+    // https://github.com/AdguardTeam/Scriptlets/issues/489
     const NOW_VALUE_KEYWORD = '$now$';
     const CURRENT_DATE_KEYWORD = '$currentDate$';
     const CURRENT_ISO_DATE_KEYWORD = '$currentISODate$';

tests/scriptlets/trusted-set-cookie-reload.spec.js

@@ -84,6 +84,33 @@ describe('Test trusted-set-cookie-reload scriptlet', () => {
         clearCookie(cName);
     });
 
+    test('Set cookie with current ISO date value and reload', () => {
+        const cName = '__test-cookie_current_date_reload';
+        const cValue = '$currentISODate$';
+        const expiresSec = '';
+        const cPath = '/';
+
+        trustedSetCookieReload(sourceParams, cName, cValue, expiresSec, cPath);
+
+        // Some time will pass between calling scriptlet
+        // and jest running test
+        const cookieValue = parseCookieString(document.cookie)[cName];
+        // Check only day, month and year
+        const currentISODate = new Date().toISOString().split('T')[0];
+        const dateDiff = cookieValue.split('T')[0];
+
+        expect(dateDiff.startsWith(currentISODate)).toBeTruthy();
+        expect(document.cookie.includes(cName)).toBeTruthy();
+        expect(window.location.reload).toHaveBeenCalledTimes(1);
+        expect(window.hit).toBe('FIRED');
+
+        // Run scriptlet again to check if reload is called
+        trustedSetCookieReload(sourceParams, cName, cValue, expiresSec, cPath);
+        expect(window.location.reload).toHaveBeenCalledTimes(1);
+
+        clearCookie(cName);
+    });
+
     test('Set cookie string', () => {
         const cName = '__test-cookie_OK';
         const cValue = 'OK';