rate-limit.middleware.ts

import { container } from 'tsyringe';
import { RateLimiterRedis } from 'rate-limiter-flexible';
import httpStatus from 'http-status';
import ms from 'ms';

import { ErrorResponse } from '@shared/utils/response.util';
import { RedisClient } from '@shared/utils/redis/redis-client/redis-client';
import { RateLimitingConfig } from '@shared/types/general.type';

const redisClient = container.resolve(RedisClient).get();

const initRateLimiter = (rateLimitingConfig: RateLimitingConfig) => {
  const rateLimiterRedis = new RateLimiterRedis({
    storeClient: redisClient,
    keyPrefix: 'rate-limiter',
    points: rateLimitingConfig.maxRequests,
    duration: ms(rateLimitingConfig.window) / 1000,
  });

  return async (req, res, next) => {
    try {
      await rateLimiterRedis.consume(req.headers?.authorization || req.headers['x-forwarded-for'] || req.socket?.remoteAddress);
      return next();
    } catch (err) {
      const rlResIp = await rateLimiterRedis.get(req.headers?.authorization || req.headers['x-forwarded-for'] || req.socket.remoteAddress);
      const retrySecs = Math.round(rlResIp.msBeforeNext / 1000) || 1;

      res.send(ErrorResponse('Too many requests'), httpStatus.TOO_MANY_REQUESTS, { 'Retry-After': String(retrySecs) });
    }
  };
};

export default initRateLimiter;