- From: Mark Baker <distobj@acm.org>
- Date: Sun, 21 Oct 2012 17:19:39 -0400
- To: Ruben Verborgh <ruben.verborgh@ugent.be>
- Cc: David Wood <david@3roundstones.com>, "Linked Data Platform (LDP) Working Group" <public-ldp-wg@w3.org>
On Sun, Oct 21, 2012 at 3:53 PM, Ruben Verborgh <ruben.verborgh@ugent.be> wrote: > Hi Mark, > >> Nothing else can be promised by servers or expected by clients, >> at least without defining HTTP extensions. > > Why not? > Any server is allowed to promise something more. Only with an HTTP extension, yes. > If the client understands this promise, it can make use of the consequences. > If it doesn’t, then it just uses HTTP (and that will work if there’s no contradiction). > >> As I mentioned before, servers are free to >> *do* more, as that's an implementation consideration that HTTP doesn't >> generally concern itself with. > > True, and the LDP spec defines a class of such servers. > >> But clients cannot *expect* more, >> because expectation is defined by the contract alone. > > They can expect more if they agree this contract is the LDP spec, > which is what an BPR client and BPR server will do. Only if that contract is explicit in the message(s), and that requires an HTTP extension. > > I’ve tried to summarize the possible options in a yes/no diagram: > > Currently, can BPR clients talk to BPR servers? Yes. > Can generic HTTP clients talk to BPR servers? Yes. > Can other RFC2616-compliant intermediaries talk to BPR servers? Yes. > > Can BPR clients talk to generic RFC2616 servers? No. Should they? No. Whoa, that was unexpected. Before I pick apart why that's an awful idea, I'd like to ask whether others agree or disagree. > If a client is designed for BPR servers, it can only be expected to work with BPR servers. > Unless it's also a generic HTTP client. But then, it will apply the regular HTTP rules > for non-BPR resources (otherwise, it’s not a generic HTTP client). Oh my ... :( Mark.
Received on Sunday, 21 October 2012 21:20:08 UTC