Readwise MCP Server

import { RateLimiter, withRetry } from '../../src/utils/rate-limiter.js'; describe('RateLimiter', () => { beforeEach(() => { jest.useFakeTimers(); }); afterEach(() => { jest.useRealTimers(); }); describe('constructor', () => { it('should create a rate limiter with provided options', () => { const limiter = new RateLimiter({ maxRequests: 10, windowMs: 1000, minDelayMs: 50 }); expect(limiter).toBeInstanceOf(RateLimiter); expect(limiter.getQueueSize()).toBe(0); expect(limiter.getCurrentWindowRequests()).toBe(0); }); it('should use default minDelayMs when not provided', () => { const limiter = new RateLimiter({ maxRequests: 10, windowMs: 1000 }); expect(limiter).toBeInstanceOf(RateLimiter); }); }); describe('acquire', () => { it('should immediately acquire when under rate limit', async () => { const limiter = new RateLimiter({ maxRequests: 5, windowMs: 1000, minDelayMs: 0 }); const acquirePromise = limiter.acquire(); // Process any pending timers jest.runAllTimers(); await acquirePromise; expect(limiter.getCurrentWindowRequests()).toBe(1); }); it('should queue requests when at rate limit', async () => { jest.useRealTimers(); // Use real timers for this test const limiter = new RateLimiter({ maxRequests: 2, windowMs: 100, // Short window for testing minDelayMs: 0 }); // Acquire first two requests immediately await limiter.acquire(); await limiter.acquire(); expect(limiter.getCurrentWindowRequests()).toBe(2); }); it('should track multiple requests', async () => { jest.useRealTimers(); const limiter = new RateLimiter({ maxRequests: 10, windowMs: 1000, minDelayMs: 0 }); await limiter.acquire(); await limiter.acquire(); await limiter.acquire(); expect(limiter.getCurrentWindowRequests()).toBe(3); }); }); describe('getQueueSize', () => { it('should return 0 when queue is empty', () => { const limiter = new RateLimiter({ maxRequests: 5, windowMs: 1000 }); expect(limiter.getQueueSize()).toBe(0); }); }); describe('getCurrentWindowRequests', () => { it('should return 0 when no requests have been made', () => { const limiter = new RateLimiter({ maxRequests: 5, windowMs: 1000 }); expect(limiter.getCurrentWindowRequests()).toBe(0); }); it('should only count requests within the window', async () => { jest.useRealTimers(); const limiter = new RateLimiter({ maxRequests: 10, windowMs: 50, // Very short window minDelayMs: 0 }); await limiter.acquire(); expect(limiter.getCurrentWindowRequests()).toBe(1); // Wait for the window to expire await new Promise(resolve => setTimeout(resolve, 60)); expect(limiter.getCurrentWindowRequests()).toBe(0); }); }); }); describe('withRetry', () => { beforeEach(() => { jest.useFakeTimers(); }); afterEach(() => { jest.useRealTimers(); }); it('should return result immediately on success', async () => { const fn = jest.fn().mockResolvedValue('success'); const result = await withRetry(fn); expect(result).toBe('success'); expect(fn).toHaveBeenCalledTimes(1); }); it('should retry on failure and eventually succeed', async () => { jest.useRealTimers(); const fn = jest.fn() .mockRejectedValueOnce(new Error('First failure')) .mockRejectedValueOnce(new Error('Second failure')) .mockResolvedValue('success'); const result = await withRetry(fn, { maxRetries: 3, baseDelayMs: 10, // Short delay for testing maxDelayMs: 100 }); expect(result).toBe('success'); expect(fn).toHaveBeenCalledTimes(3); }); it('should throw after max retries exceeded', async () => { jest.useRealTimers(); const fn = jest.fn().mockRejectedValue(new Error('Always fails')); await expect(withRetry(fn, { maxRetries: 2, baseDelayMs: 10, maxDelayMs: 50 })).rejects.toThrow('Always fails'); expect(fn).toHaveBeenCalledTimes(3); // Initial + 2 retries }); it('should not retry when shouldRetry returns false', async () => { jest.useRealTimers(); const fn = jest.fn().mockRejectedValue(new Error('Non-retryable error')); await expect(withRetry(fn, { maxRetries: 3, baseDelayMs: 10, shouldRetry: () => false })).rejects.toThrow('Non-retryable error'); expect(fn).toHaveBeenCalledTimes(1); }); it('should use shouldRetry callback correctly', async () => { jest.useRealTimers(); const retryableError = { type: 'retryable' }; const nonRetryableError = { type: 'non-retryable' }; const fn = jest.fn() .mockRejectedValueOnce(retryableError) .mockRejectedValueOnce(nonRetryableError); await expect(withRetry(fn, { maxRetries: 5, baseDelayMs: 10, shouldRetry: (error: any) => error?.type === 'retryable' })).rejects.toEqual(nonRetryableError); expect(fn).toHaveBeenCalledTimes(2); }); it('should use default options when not provided', async () => { const fn = jest.fn().mockResolvedValue('result'); const result = await withRetry(fn); expect(result).toBe('result'); }); it('should cap delay at maxDelayMs', async () => { jest.useRealTimers(); const startTime = Date.now(); const fn = jest.fn() .mockRejectedValueOnce(new Error('fail')) .mockResolvedValue('success'); await withRetry(fn, { maxRetries: 1, baseDelayMs: 10000, // Very long base delay maxDelayMs: 50 // But capped at 50ms (plus jitter up to 1000ms) }); const elapsed = Date.now() - startTime; // Should be capped around 50ms + jitter (up to 1000ms), so well under 10000ms expect(elapsed).toBeLessThan(2000); }); });