- From: Jeffrey Mogul <mogul@pa.dec.com>
- Date: Wed, 09 Jul 97 17:50:23 MDT
- To: Henrik Frystyk Nielsen <frystyk@w3.org>
- Cc: http-wg@cuckoo.hpl.hp.com
Proposed changes to Section 13.6, 4th Paragraph:
RFC2068:
The Vary header field may also inform the cache that the
representation was selected using criteria not limited to the
request-headers; in this case, a cache MUST NOT use the response in
a reply to a subsequent request unless the cache relays the new
request to the origin server in a conditional request and the
server responds with 304 (Not Modified), including an entity tag or
Content-Location that indicates which entity should be used.
Henrik proposed:
The Vary header field MUST also inform the cache that the
representation was selected using criteria not limited to the
request-headers; in this case, a cache MUST NOT use the response in
a reply to a subsequent request unless the cache relays the new
request to the origin server in a conditional request and the
server responds with 304 (Not Modified), including an entity tag or
Content-Location that indicates which entity should be used.
Koen changed one word:
The Vary header field MUST also inform the cache *if* the
representation was selected using criteria not limited to the
request-headers; in this case, a cache MUST NOT use the response in
a reply to a subsequent request unless the cache relays the new
request to the origin server in a conditional request and the
server responds with 304 (Not Modified), including an entity tag or
Content-Location that indicates which entity should be used.
I think the first part is still somewhat misleading. How about:
If the representation was selected using criteria not limited to
the request-headers, then the server MUST include a "Vary: *"
header field in the response.
In this case, a cache MUST NOT use the response in
a reply to a subsequent request unless the cache relays the new
request to the origin server in a conditional request and the
server responds with 304 (Not Modified), including an entity tag or
Content-Location that indicates which entity should be used.
As long as we are going to say MUST, we should be explicit about
what the requirement is.
-Jeff
Received on Wednesday, 9 July 1997 17:56:39 UTC