Cache-Control

MDN Cache-Control
https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/http-caching
https://support.cloudflare.com/hc/en-us/articles/115003206852-Understanding-Origin-Cache-Control
max-age=0 vs no-cache
- https://stackoverflow.com/a/1383359/1870054
If-None-Match
- W/ weak validator
- GET, HEAD
- 值为 etag, 存在则返回 304 Not Modified
- 修改操作, 412 Precondition Failed
- If-None-Match: "<etag>"[, "<etag>"]
参考
- [RFC 9111] HTTP Caching, STD 98
  - 替代 [RFC 7234] - Hypertext Transfer Protocol (HTTP/1.1): Caching
- darkweak/souin
  - MIT, Go
  - An HTTP cache system, RFC compliant, compatible
- jaredwray/cacheable
  - MIT, NodeJS
  - node http request
- undici http caching
  - https://undici.nodejs.org/#/docs/api/CacheStorage.md
  - nodejs/undici#3562
- natemoo-re/ultrafetch
  - MIT, TS
  - fetch

请求

Cache-Control: max-age=<seconds>
Cache-Control: max-stale[=<seconds>]
Cache-Control: min-fresh=<seconds>
Cache-Control: no-cache
Cache-Control: no-store
Cache-Control: no-transform
Cache-Control: only-if-cached

响应

Cache-Control: must-revalidate
Cache-Control: no-cache
Cache-Control: no-store
Cache-Control: no-transform
Cache-Control: public
Cache-Control: private
Cache-Control: proxy-revalidate
Cache-Control: max-age=<seconds>
Cache-Control: s-maxage=<seconds>

Cache-Control: immutable
Cache-Control: stale-while-revalidate=<seconds>
Cache-Control: stale-if-error=<seconds>

private - 面向单用户 - Authorization - browser 缓存
public - 多用户共享缓存 - proxy cache 缓存
post-check
pre-check
immutable
- max-age 内避免尝试校验缓存

# 单位为秒
Cache-Control: public, max-age=3600
Expires: Thu, 01 Dec 2014 16:00:00 GMT

Cache-Control: public, max-age=86400
- static asset
Cache-Control: no-store
- 不缓存
Cache-Control: private, max-age=3600
- 浏览器缓存但 Proxy 不缓存
Cache-Control: public, no-cache
- prefer revalidation when served
Cache-Control: public, no-cache, proxy-revalidate or Cache-Control: public, s-maxage=0
- Cache assets in proxy caches but REQUIRE revalidation by the proxy when served
Cache-Control: public, no-cache, must-revalidate
- Cache assets in proxy caches, but REQUIRE revalidation by any cache when served
Cache-Control: public, no-transform
- Cache assets, but ensure the proxy does not modify it
Cache-Control: public, max-age=3600, stale-if-error=60
- Cache assets with revalidation, but allow stale responses if origin server is unreachable
Cache-Control: public, max-age=7200, s-maxage=3600
- Cache assets for different amounts of time on Cloudflare and in visitor browsers
Cache-Control: max-age=600, stale-while-revalidate=30
- Cache an asset and serve while asset is being revalidated
https://developers.cloudflare.com/cache/about/cache-control

平台

x-vercel-cache
- HIT, MISS
x-vercel-id
cf-cache-status
- HIT, MISS, EXPIRED, DYNAMIC, BYPASS

平台​

平台