HTTP Caching

Expires (HTTP/1.0) was deprecated, use Cache-Control instead in HTTP/1.1.

Normal Use

Response

Last-Modified: xxx
Cache-Control: max-age=86400
Age: 3600
ETag: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Request

If-Modified-Since: xxx
If-Match: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
If-None-Match: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
ETag: bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

Vary: User-Agent
Vary: Accept-Encoding

Forcing Reloading (Request)

Cache-Control: no-cache

Static Files

Cache-Control: public, max-age=15552000, immutable
Age: 2592000
ETag: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Dynamic Request

Cache-Control: no-store

Only for client browser

Cache-Control: private, max-age=86400
ETag: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

References