Handling E-commerce Sales: Surviving "Black Friday" Traffic Surges

Major e-commerce sales (like 11.11, Black Friday) are the annual final exam for tech teams. Traffic can spike 100x in seconds. How to ensure the system doesn't crash?

1. Extreme Static/Dynamic Separation

90% of requests (images, CSS, JS, detail page HTML) should be intercepted at the CDN edge. We recommend aggressive caching policies: for hash-fingerprinted files (like `app.v1.css`), set `Cache-Control: public, max-age=31536000, immutable` to ensure they never need origin validation.

2. Queueing & Rate Limiting for Inventory APIs

For dynamic APIs like `/api/buy`, CDNs can't cache but can act as a shield. Using CDN Engine's WAF module, you can configure **"Leaky Bucket"** rate limiting. When request rates exceed backend capacity (e.g., 5000 QPS), edge nodes serve a friendly "In Queue" page instead of letting requests crush the database.

3. Blocking Scalper Bots

Use fingerprint recognition to block automated scripts. If the same device fingerprint initiates 10 order requests within 1 second, the WAF automatically blacklists it for 24 hours.