ldp-ISSUE-32 (discovery): How can clients discover that a resource is an LDPR or LDPC, and what features are supported? [Linked Data Platform core]

ldp-ISSUE-32 (discovery): How can clients discover that a resource is an LDPR or LDPC, and what features are supported? [Linked Data Platform core]

http://www.w3.org/2012/ldp/track/issues/32

Raised by: Richard Cyganiak
On product: Linked Data Platform core

Currently, the spec doesn't have a reliable mechanism that would allow a client to discover whether a resource is an LDPR, and what features exactly are supported by an LDPC. For example, a client has to guess whether xxx?firstPage will return anything, or whether xxx?non-member-properties does something useful. This means that clients will have to make lots of speculative HTTP requests trying to find out whether certain features are supported. Same for trying to update an LDPR via PUT — the client has no way of knowing whether it even is an LDPR.

I think this is wasteful, will make clients brittle, and doesn't exactly honour the URI opacity axiom.

Servers should be able to announce their capabilities to clients, so that clients can discover them without blindly poking around. This could be done in various ways—via OPTIONS, via HTTP headers, via links in the RDF representations, and perhaps other ways.

This is related to ISSUE-7 and the notion of discoverable “container/resource affordances”.

Received on Monday, 5 November 2012 20:42:24 UTC