Fallback to 0.3 discovery

Question

Fallback to 0.3 discovery

Closed this issue 13 years ago · 4 comments

It would be nice if discovery could fall back to the 0.3 mechanism for certain data types, if the expected headers aren't there.

For Atom (application/atom+xml), look for <link rel="hub"> in the feed.
For RSS (application/rss+xml), look for <atom:link rel="hub"> in the feed.

Answer 1 · 2012-02-23T17:48:14.000Z

I'm not sure this belongs to the spec. I really really want to make the spec easier. But it's obvious to me that a good client should be able to fall back to 0.3 mechanisms.
For me it's more a matter of implementation than a matter of spec.

Answer 2 · 2012-02-23T19:32:44.000Z

I suggest using SHOULD instead of MUST for HTTP Link header discovery, and then say something like:

Hub implementations MAY try alternative sources to establish the location of hubs for a particular resource, including HTML and Atom Link elements as defined in appendices A and B of RFC 5988.

Answer 3 · 2012-02-24T09:47:07.000Z

@ralphm Feel free to send a pull request :) I'm not sure where you want me to put that in pubsubhubbub-core-0.4.xmlin the futurebranch.

Answer 4 · 2012-02-24T13:33:24.000Z

I was also tempted to include some of the 'best practice' text on hubs performing heuristics for resource equivalence. Why was that removed? I understand if it is REQUIRED to include the link header with rel=self, this problem doesn't exist. In reality, though, this might still be good advice.