W3C home > Mailing lists > Public > ietf-http-wg@w3.org > July to September 2009

Re: Input on request for link relation

From: John Panzer <jpanzer@acm.org>
Date: Fri, 11 Sep 2009 11:34:11 -0700
Message-ID: <30ac519d0909111134t78222aa7obb3deaaf8d5ffdcf@mail.gmail.com>
To: Jan Algermissen <algermissen1971@mac.com>
Cc: Lisa Dusseault <lisa.dusseault@gmail.com>, Atom-Syntax Syntax <atom-syntax@imc.org>, ietf-http-wg@w3.org, bslatkin@google.com
Jan -- The text you're concerned about is part of the draft protocol at
http://pubsubhubbub.googlecode.com/svn/trunk/pubsubhubbub-core-0.2.html#contentdistributionso
I think this is a (legitimate) question/critique of the draft spec and
should be taken up over at http://groups.google.com/group/pubsubhubbub.
(+Brett).

On Thu, Sep 10, 2009 at 4:57 PM, Jan Algermissen <algermissen1971@mac.com>wrote:

>
> On Sep 11, 2009, at 1:31 AM, John Panzer wrote:
>
>  Without getting into the appropriate discussion form question, what hub
>> resource semantics (and link relation definition) are you referring to
>> exactly?  I can't seem to find it, and it's hard to understand your
>> objection without it.
>>
>
> Section 7.3 says:
>
> "If, after a content fetch, the hub determines that the topic feed content
> has changed, the hub MUST send information about the changes to each of the
> subscribers to the topic."
>
> I understand this to imply that subscribers expect the hub to definitely
> send the notifications. What if the hub decides not to due to the number of
> subscribers it has? Or to turn this around: how would a subscriber ever know
> whether not receiving notifications means that there are not updates or that
> the hub stopped sending notifications.
>
> Jan
>
>
>
>
>
>> On Thu, Sep 10, 2009 at 12:40 PM, Jan Algermissen <
>> algermissen1971@mac.com> wrote:
>>
>> Lisa,
>>
>> not sure the following it is appropriate to discuss this here, so please
>> redirect me to the proper place if so.
>>
>> Hubs are being discovered by clients by way of the 'hub' link relation. I
>> am
>> concerned that the semantics of a hub resource (provided by the link
>> relation
>> definition) are imposing obligations on the server that are contrary what
>> one
>> would expect to see in the HTTP world.
>>
>> Or in other words: I think that the assumptions a client makes about the
>> behaviour
>> of a hub are too rigid. If a hub has more subscribers than it knows it can
>> handle
>> it might well decide not to notify them. A situation like this is
>> impossible to
>> prevent by the specification and I think the server should therefore
>> explicitly be
>> given much more freedom regarding its behavior upon a ping.
>>
>> Especially given the use of Atom which in a sense implies a very
>> unconstrained
>> protocol.
>>
>> (Sorry if this discussion is already going on elsewhere)
>>
>> Jan
>>
>>
>>
>> On Sep 10, 2009, at 7:30 PM, Lisa Dusseault wrote:
>>
>>
>> Comments welcome on the following request
>>
>> thx,
>> lisa
>>
>> ---
>> General Request for Assignments (link-relations)
>>
>> Contact Name :
>> Brett Slatkin
>>
>> Type of Assignment :
>> I want to add a new Atom Link Relation type for the PubSubHubbub protocol
>>
>> (http://pubsubhubbub.googlecode.com). The relation type is "hub".
>>
>> Registry :
>> http://www.iana.org/assignments/link-relations/link-relations.xhtml
>>
>>
>> Description :
>> The new  is used for discovery of Hubs,
>> which enables real-time notifications of entries in Atom and RSS feeds.
>> Without making the relation type official, we're not in compliance with
>> the
>>
>> Atom spec.
>>
>> Additional Info :
>> http://pubsubhubbub.googlecode.com/svn/trunk/pubsubhubbub-core-0.1.html
>>
>>
>>
>>
>
Received on Friday, 11 September 2009 18:34:56 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Friday, 27 April 2012 06:51:10 GMT