Capability discovery

[Josh Hoyt]

On 12/5/05, Ernst Johannes <jernst+lists.danga.com at netmesh.us> wrote:
> Given an identity URL, the capabilities of this URL must be
> discoverable through at least one of the following mechanisms:
>
> 1) An HTTP GET with the Accept MIME type of "application/xrd+xml"
> returns the capabilities document directly.
>
> 2) A response to an HTTP GET to the identity URL returns a custom
> HTTP header, 'X-YADIS-Location' with a value that is a URL. The
> capabilities document is returned from that second URL.
>
> 3) A response to an HTTP GET to the identity URL returns an HTML
> document that contains a META HTTP-EQUIV statement, whose value is a
> URL. The capabilities document is returned from that second URL.

As I understood it, the URL MUST support 2 or 3 but MAY support 1. If
the URL supports only number one, it may not work with some relying
parties.

Specifically, we are not requiring relying parties to attempt to do
content negotiation.

Josh