Intlayer

import type { Response } from 'express'; import rateLimit, { ipKeyGenerator, type Options, type RateLimitRequestHandler, } from 'express-rate-limit'; import { ErrorHandler } from './errors'; // ------------------------------------------------------------- // Create the rate-limiter instances once at module load-time so // that the hit counters are shared across every incoming request. // ------------------------------------------------------------- const ipLimiterOptions: Partial<Options> = { windowMs: 60 * 1000, // 1-minute window limit: 500, // 500 requests / IP / window standardHeaders: 'draft-8', legacyHeaders: false, // Use a custom key generator that handles proxy headers securely keyGenerator: (req) => { // Normalize IPv6 to subnet using helper to avoid bypasses return ipKeyGenerator(req.ip ?? req.socket?.remoteAddress ?? 'unknown'); }, handler: (req, res) => { const { limit, remaining, resetTime } = (req as any).rateLimit; ErrorHandler.handleGenericErrorResponse( res as unknown as Response, 'RATE_LIMIT_EXCEEDED', { limit: `${limit} per minute`, retryAfter: Math.ceil((resetTime?.getTime() - Date.now()) / 1000), remaining, } ); }, }; // Fix type error of express-rate-limit export const ipLimiter: any = rateLimit( ipLimiterOptions ) satisfies RateLimitRequestHandler; const unauthenticatedChatBotLimiterOptions: Partial<Options> = { windowMs: 60 * 60 * 1000, // 1-hour window limit: 3, // 3 requests / IP / window standardHeaders: 'draft-8', skip: (_req, res) => Boolean(res.locals.user), // authenticated? then skip legacyHeaders: false, // Use a custom key generator that handles proxy headers securely keyGenerator: (req) => { // Normalize IPv6 to subnet using helper to avoid bypasses return ipKeyGenerator(req.ip ?? req.socket?.remoteAddress ?? 'unknown'); }, handler: (req, res) => { const { limit, remaining, resetTime } = (req as any).rateLimit; ErrorHandler.handleGenericErrorResponse( res as unknown as Response, 'RATE_LIMIT_EXCEEDED_UNAUTHENTICATED', { limit: `${limit} per hour`, retryAfter: Math.ceil((resetTime?.getTime() - Date.now()) / 1000), remaining, } ); }, }; // Fix type error of express-rate-limit export const unauthenticatedChatBotLimiter: any = rateLimit( unauthenticatedChatBotLimiterOptions ) satisfies RateLimitRequestHandler;