flexport-rate-limits

# Flexport Rate Limits ## Overview The Flexport API v2 enforces rate limits per API key. When exceeded, you get a `429 Too Many Requests` with `Retry-After` and `X-RateLimit-*` headers. Key limits to know: the API returns headers on every response telling you remaining quota. ## Rate Limit Headers | Header | Description | Example | |--------|-------------|---------| | `X-RateLimit-Limit` | Max requests per window | `100` | | `X-RateLimit-Remaining` | Remaining in current window | `47` | | `X-RateLimit-Reset` | Unix timestamp when window resets | `1711234567` | | `Retry-After` | Seconds to wait (only on 429) | `30` | ## Instructions ### Step 1: Monitor Rate Limit Headers ```typescript class RateLimitTracker { remaining = Infinity; resetAt = 0; update(headers: Headers) { this.remaining = parseInt(headers.get('X-RateLimit-Remaining') || '100'); this.resetAt = parseInt(headers.get('X-RateLimit-Reset') || '0') * 1000; } async waitIfNeeded() { if (this.remaining <= 2 && Date.now() < this.resetAt) { const wait = this.resetAt - Date.now() + 100; console.log(`Rate limit near. Waiting ${wait}ms`); await new Promise(r => setTimeout(r, wait)); } } } ``` ### Step 2: Exponential Backoff with Jitter ```typescript async function flexportWithRetry<T>( fn: () => Promise<Response>, maxRetries = 4 ): Promise<T> { for (let attempt = 0; attempt <= maxRetries; attempt++) { const res = await fn(); if (res.ok) return res.json(); ...