- From: Mark Nottingham <mnot@mnot.net>
- Date: Mon, 16 Jul 2012 16:05:13 +1000
- To: HTTP Working Group <ietf-http-wg@w3.org>
I haven't heard anything else about this, so I've marked the proposal below for incorporation. On 05/07/2012, at 1:00 PM, Mark Nottingham wrote: > > On 25/06/2012, at 1:48 PM, Mark Nottingham wrote: >>> >>> 3. Precondition Header Fields >>> >>> This section defines the syntax and semantics of HTTP/1.1 header >>> fields for applying preconditions on requests. <new>If an origin server >>> supplies a Validator for a resources, the origin server MUST support the >>> corresponding conditionals.</new> >> >> That looks reasonable, but I think it'd be clearer if this were stated in the sections that define the validators. E.g., in <https://svn.tools.ietf.org/svn/wg/httpbis/draft-ietf-httpbis/latest/p4-conditional.html#entity.tag.generation>, add: >> >> """ >> Origin servers that generate ETags for a resource MUST support the If-Match precondition [ref] on all subsequent unsafe requests to that resource, and SHOULD support it for subsequent safe requests. >> """ >> >> ... and likewise for Last-Modified / If-Unmodified-Since. Thoughts? > > > A slight refinement. > > """ > Origin servers that include ETags in responses for a resource MUST honour the If-Match precondition [ref] when sending a successful response to any subsequent unsafe requests, and ought to support it for subsequent safe requests. > """ > > ... and likewise for Last-Modified / If-Unmodified-Since. > > The one thing this doesn't catch is: > > If-None-Match: * > > because a client can send that to indicate that it only wants to PUT something (for example) when there's nothing already there (theoretically, If-Match: * is like this too). > > This is a bit awkward; without this caveat, we could make p4 a self-contained optional extension (since LM and ETags are both defined here too). > > My inclination here is to document this requirement in PUTs definition, and advise new methods to document whether they require it too. > > Thoughts? > > -- > Mark Nottingham http://www.mnot.net/ > > > > -- Mark Nottingham http://www.mnot.net/
Received on Monday, 16 July 2012 06:05:46 UTC