Hacktoberfest 2026: những issue maintainer đã đánh dấu cho tháng Mười, đang mở và phù hợp người mới. Xem issue Hacktoberfest

Build the rate limiter on the new CounterStore, so limits hold across server instances

Đang mở
  • Có gì không ổn?
#245 0 bình luận 0 reaction 0 người được giao Xem trên GitHub

Maintainer thường phản hồi trong vòng 1 ngày

Chưa có ai nhận issue này.

Đánh giá

Độ khó
3/5
Thời gian dự kiến
1-2 ngày
Mức phù hợp với người mới
83/100
Loại issue
Tính năng
Độ rõ ràng
Đặc tả rõ ràng
Mức độ hoạt động
Sôi nổi
Công nghệ
node.js, typescript
Lĩnh vực
backend, databases

Hướng nghiên cứu

Read packages/core/src/storage/types.ts for the CounterStore contract, then review packages/server/src/rate-limit.ts and its tests for existing behavior. Implement the algorithm in packages/core/src/limits/rate-limit.ts and add fake-clock and concurrency coverage in packages/core/tests/limits/rate-limit.test.ts, using the in-memory counter store. Done means the listed acceptance criteria pass and the core package exports the limiter with a minor changeset.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.

Mô tả

core enhancement hacktoberfest help wanted

The server's rate limiter keeps its counts in a Map in the process (packages/server/src/rate-limit.ts). On Vercel or Workers every instance has its own map, so a visitor spread over five instances gets five times the limit. It also needs a setInterval for cleanup (packages/server/src/handler.ts, line 35), and Workers don't allow timers at global scope.

@chatcops/core now has a CounterStore interface (packages/core/src/storage/types.ts): atomic counters that reset after a while, backed by Redis, Postgres and so on. This issue is the rate limit algorithm on top of it. Wiring it into the server comes in a later PR.

What to do
Create packages/core/src/limits/rate-limit.ts:

export interface RateLimitRule {
  limit: number;      // requests allowed per window
  windowMs: number;
}

export interface RateLimitResult {
  allowed: boolean;
  /** Requests left in the current window, never below 0. */
  remaining: number;
  /** When denied: how long until a request would be allowed again. */
  retryAfterMs?: number;
}

export function createRateLimiter(counters: CounterStore, rule: RateLimitRule, options?: { prefix?: string; now?: () => number }): {
  check(key: string): Promise<RateLimitResult>;
};

Use a sliding window built from two fixed windows. It's smooth at window edges (no burst of 2x the limit at the boundary) and needs only two counters:

  • The window index is Math.floor(now / windowMs). Count this request with counters.increment(${prefix}:${key}:${index}, 1, 2 * windowMs), and read the previous window's counter with get.
  • The estimated count is previous * (1 - elapsedInWindow / windowMs) + current. Allow the request when it's at most limit.
  • Denied requests still count, so a client that keeps hammering stays limited.
  • retryAfterMs is an estimate: the time until the estimate drops back under the limit, at least 1 ms and at most windowMs. Explain the formula in a comment.
  • prefix defaults to 'rl'. Validate limit > 0 and windowMs > 0 like RateLimiter does.

Where to look

  • packages/server/src/rate-limit.ts (today's limiter and its tests in packages/server/tests/rate-limit.test.ts)
  • packages/core/src/storage/memory.ts (memoryStorage().counters, use it in the tests with a fake now)
  • Cloudflare's write-up of the same sliding window idea

Acceptance criteria

  • New packages/core/src/limits/rate-limit.ts and packages/core/tests/limits/rate-limit.test.ts, exported from @chatcops/core
  • Tests with a fake clock: the first limit requests pass and the next one doesn't; the count decays across the window boundary (half the previous window still counts at the midpoint); keys don't affect each other; retryAfterMs is set when denied and within bounds
  • A test with 30 concurrent check() calls against a limit of 10 allows exactly 10
  • Changeset for @chatcops/core (minor)
  • pnpm test:coverage and pnpm lint pass

Want to work on this? Comment below and I'll assign it to you. Please take one issue at a time, branch off dev, and open your PR against dev with Closes #<this issue number>. Setup notes (pnpm, build before test) are in CONTRIBUTING.md.

Ngôn ngữ chính
TypeScript
Star
13
Fork
7
Merge trung bình
4 giờ 11 phút
Pull request đã merge (30 ngày)
122

Chuẩn bị môi trường

Bắt đầu từ đâu

  1. Đọc hết issue, rồi đọc hướng dẫn đóng góp của dự án.
  2. Bình luận trên issue rằng bạn sẽ nhận — tránh hai người làm cùng một việc.
  3. Fork repository và làm thay đổi trên một nhánh.
  4. Mở pull request có tham chiếu số hiệu của issue.

Issue khác của codercops/chatcops

Tất cả issue của codercops/chatcops

Issue tương tự

Thêm issue về TypeScript

Nhận issue mới trong hộp thư của bạn

Bản tóm tắt ngắn những issue GitHub phù hợp với người mới.