HTTP Discovery

HTTP Discovery Taking Resource URI and finding metadata

Requirements:

• Should be able to get the metadata without accessing the resource.
  • You don't know what it is yet, so you shouldn't be interact with it yet.
• The the resource can point at its metadata.
• Must be accessible to different levels of developers.
  • Can't *just* require headers. Must also support an HTML solution.
• Must work with web architecture.
• Must be friendly to little and big players.
  • The same solution for your blog should work for a large company.

Background for the following table is at Eran Hammer-Lahav's blog post.

	Resource Declaration	Direct Metadata Access	Web Compliant	Scale Agnostic	Extendable
1. HTTP Response Header (Link, X-XRDS-Location)	+		+
2. HTTP Response Header over HEAD	+			+	+
3. HTTP Header Negotiation	+			+/-
4. HTML <Link> Element (<Meta>)	+		+	+
5. HTTP Content Negotiation (Accept)		+
6. HTTP OPTIONS Method		+	+		+
7. WebDAV PROPFIND Method (MGET, ARK)		+/-	+/-		+/-
8. Custom HTTP Method		+			+
9. Static Resource Mapping (Prefix, Suffix)		+	+/-	+/-
10.Dynamic Resource Mapping (Templates, /site-meta)	+/-	+	+	+/-	+/-

A combination of 1, 4 and 10 seem promising.

For dynamic mapping:

a. DNS

b. Known Location (like /robots.txt)

b is the /site-meta proposal.

This session was also written up on Drummond Reed's blog post XRD Begins.