@canmertinyo/rate-limiter-redis/src/redis.storage.ts

A simple rate-limiting middleware for Express.js with support for in-memory, Redis, and MongoDB storage

import { RateLimiter, RateLimitRecord } from "@canmertinyo/rate-limiter-core";
import Redis, { RedisOptions } from "ioredis";

export class RedisStorage implements RateLimiter {
  private redis!: Redis;

  constructor(private readonly options: RedisOptions) {}

  async initialize(): Promise<RateLimiter> {
    this.redis = new Redis(this.options);
    return this;
  }

  public async getRateLimitRecord(
    key: string
  ): Promise<RateLimitRecord | undefined> {
    const data = await this.redis.get(key);
    return data ? (JSON.parse(data) as RateLimitRecord) : undefined;
  }

  public async createRateLimitRecord(
    record: RateLimitRecord
  ): Promise<RateLimitRecord> {
    await this.redis.set(record.key, JSON.stringify(record));
    return record;
  }

  public async updateRateLimitRecord(
    key: string,
    timestamp: number,
    count: number
  ): Promise<RateLimitRecord> {
    const record = await this.getRateLimitRecord(key);
    if (!record) throw new Error("Record not found");

    const updatedRecord: RateLimitRecord = {
      ...record,
      count,
      timestamp,
    };
    await this.redis.set(key, JSON.stringify(updatedRecord));
    return updatedRecord;
  }

  public async increment(key: string): Promise<RateLimitRecord> {
    const record = await this.getRateLimitRecord(key);
    if (!record) throw new Error("Record not found");

    const updatedRecord: RateLimitRecord = {
      ...record,
      count: record.count + 1,
    };
    await this.redis.set(key, JSON.stringify(updatedRecord));
    return updatedRecord;
  }
}