Gateway RidgeISSUE #6 of 35

caching · vary · cache-control · expires

Gateway GusVSTimeout Titan

Gateway Gus saysCache-Control directives tell clients and proxies how long and how to cache.

Cache-Control is the master switch: max-age=300 (cache 5 min), no-cache (revalidate before use), no-store (never cache — for sensitive data), private (browser only, not shared proxies), public (anyone). Vary tells caches which request headers affect the response (e.g. Vary: Accept-Encoding). Get these right and you cut load dramatically.

Power-ups you unlock

max-age, no-cache, no-store, private, public
no-store for sensitive data
Vary names headers that change the response
Correct directives cut server load

Timeout Titan attacks — common mistakes

no-cache vs no-store confusion
Caching personalized data as public
Forgetting Vary, serving wrong cached variants

Boss battleChoose Cache-Control for: a public logo, and a user’s account page.

Example code

<!doctype html><html><head><meta charset="utf-8"></head>
<body style="background:#06040d;color:#e6e0ff;font-family:monospace;padding:20px"><pre>logo:    Cache-Control: public, max-age=86400
account: Cache-Control: private, no-store</pre></body></html>

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