Re: [xri] Quick overview of descriptor discovery flow

["David Fuelling" <david.fuelling@cordance.net>]

On Mon, Dec 15, 2008 at 9:02 PM, Eran Hammer-Lahav <eran@hueniverse.com> wrote:

If it wasn't clear, this replaces only the 'Yadis' portion of the current OpenID discovery flow. It means you can get from the URI the user entered to the XRD, and from there business as usual. If the RP supports email addresses, it can use the same process assuming a template is found to obtain the descriptor.

Note that this workflow does not convert the email to an http URI! All it does is provide the descriptor of any URI: http, mailto, or other. OpenID will still need to decide what to use as the actual identifier, but this suggest the claimed identifier is the mailto URI.

If OpenID wanted to stick with just URL's and XRI's, but still support email addresses, then couldn't a redirect be used?  For example, bootstrap the URI 'beth@example.com' to get a /site-meta, that contains the following: 

 <XRD>
        <Link>
            <Rel>describedby</Rel>
            <MediaType>application/xrd+xml</MediaType>
            <TemplateURI syntax="plain" vocabulary="uri">http://example.com?meta={uri}</TemplateURI>
            <site-meta:scheme>mailto http</site-meta:scheme>
        </Link>
    </XRD>

The TemplateURI (http://example.com?meta={uri}) is combined with the mailto: URI (for beth) to become http://example.com?meta=mailto:beth@example.com.  Dereferencing this URL could simply result in a 301/302 redirect to a new URL (http://beth.example.com) that contains Links/XRD describing beth's OpenID endpoint, and other info, with her claimed identifier being the final URL  (i.e., http://beth.example.com).

Not to say it has to be that way, but it would seem to give OpenID some flexibility in deciding what to use as a Claimed Identifier (mailto: or http:).

david