Interaction of request and response Cache-Control

[mnot@…]

The specification does not say how request Cache-Control affects the freshness algorithm, nor does it say how request CC extensions can or cannot affect response CC directives.

[mnot@…]

Partial proposal:

In 2.2, replace this:

the presented request and stored response are free from directives that would prevent its use (see Section 3.2 and Section 3.4), and

with this:

the presented request does not contain the 'no-cache' pragma (section 3.4), nor the 'no-cache' cache directive (section 3.2.1), unless the stored response is successfully validated (section 2.4).

the stored response does not contain the 'no-cache' cache directive (section 3.2.2), unless it is successfully validated (2.4).

Still to deal with: request max-age / max-stale / min-fresh

[mnot@…]

max-stale is already taken care of in 2.3.3:

A cache MUST NOT return stale responses unless it is disconnected (i.e., it cannot contact the origin server or otherwise find a forward path) or doing so is explicitly allowed (e.g., by the max- stale request directive; see Section 3.2.1).

[mnot@…]

Proposal for max-age and min-fresh --

In 2.3 Freshness Model, change

Additionally, clients might need to influence freshness calculation. They can do this using several request cache directives, with the effect of either increasing or loosening constraints on freshness. See Section 3.2.1.

to

Additionally, clients can request modifications to freshness calculation -- either constraining or relaxing it -- by using the max-age and min-fresh request cache directives. See Section 3.2.1 for details.

[mnot@…]

Fixed in [1483]:

Clarify effects of request Cache-Control; closes #293.