[TYPO3-dev] Core Behaviour: Using Cache-Control Headers to prevent _Clients_ from Caching

[Ekkehard Gümbel]

Martin Kutschker schrieb:
> Ok, how about this:
> 
> "1": send headers that allow public caching (current)
> "public": same as 1, but makes clear what is sent
> "private": send headers that allow only private caching
> "no-cache": send headers that disables caching
> 
Hmm... I am afraid that will lead to even more confusion.
Basically, sendCacheHeaders is set to enable cache-related HTTP headers - in most cases to make proxy caching 
possible in the first place.
To date, this includes surpressing proxy caching for specific pages.
Thus the decision between what you call "public" and "private" is the one that TYPO3 already makes internally.

Surpressing client-side ("private") caching is a quite different matter and may be interesting even if there 
is no proxy caching around.

 > So we have backwards compatibilty and full control.
Actually, cache-related headers do not give much control anyway since the behaviour of all those proxies and 
browsers out there vary widely.

To me, different cases are:
- I want to allow proxy caching for cachable pages
- I want to allow proxy caching for cachable pages and to surpress browser caching for everything else
- I want to surpress any caching (i.e. both proxy and browser) for all pages
(Since the internal "cachable pages" decision is already quite sophisticated, to me the latter point is not so 
important.)

### Question: Are there other potentially relevant cases? ###

Based on that information, the config style can then be defined.

greets
/Ekki