One shared 100 req / 10 min limiter counted everything —
401s, CORS preflights, even /health — so a bad-token burst
from a second frontend burned the budget and 429'd POST
/api/auth/login too, leaving no way back in short of
waiting out the window or restarting (MemoryStore reset).
New middleware/rateLimit.js holds two limiters, verified
against express-rate-limit@5.5.1:
- apiLimiter (300 / 15 min) skips OPTIONS, /health, and the
public auth endpoints, so preflights, probes, and login
attempts never drain real API budget.
- authLimiter (20 / 15 min, successful logins free) guards
register/login/forgotpassword/resetpassword against
brute force. 429 there means 20 wrong passwords, never
a busy API.
Storm-tested with live server: 320 bad-token hits burn the
global budget yet login still returns 200; 25 bad logins
trip only the login limiter while API traffic is untouched.
