On Thu, Dec 3, 2009 at 6:37 PM, Peter Saint-Andre <[email protected]>wrote:
> On 12/3/09 12:34 AM, Ville Varis wrote: > > > > > > On Thu, Dec 3, 2009 at 6:49 AM, Peter Saint-Andre <[email protected] > > <mailto:[email protected]>> wrote: > > > > http://xmpp.org/extensions/tmp/xep-0060-1.13.html > > > > The data versioning stuff is here: > > > > http://xmpp.org/extensions/tmp/xep-0060-1.13.html#versioning > > > > > > "MUST NOT be accepted by the service from the publisher," > > > > This one makes me feeling I have to use some open source implementation > > to make reliable service and to change this part by myself right to the > > code. > > > > In node level I think this requirement is ok, not in Item level. > > I'm glad we agree about the node level, at least. :) > > > Serviveces A and B are equivalent, > > What does that mean? IMHO no two pubsub services can be identical, or > maintain the same information. > > Maintain exactly same information flow. Typically back-ends connected to same datasource system/to same database. Or A and B being front-ends for original service to avoid load for original one, and to allow scalability through front-end proxies. (For some solutions removes the need for clustered solution in full) > > Service A publishes ItemID a1, with Ver a123 > > Service A publishes ItemID a1, with Ver a124 > > > > Service B publishes ItemID a1, with Ver b123 > > Service B publishes ItemID a1, with Ver b345 > > But an ItemID is unique only within the context of a given node at a > given service. ItemID a1 at NodeID foo on Service A != ItemID a1 at > NodeID bar on Service B. > > > Subscriber S receives ItemId a1 from A and B in random order, how the > > subscriber should decide, which one is the correct one to use? > > > > Subscriber S changes it's subscription from A to B and reqeust all items > > from which version? (from the beginning) > > > > Proxy server Pr acts as subscriber to A and B and as publisher to it's > > clients. Pr receives a1 from A and B, when is there time to update data > > in Pr and to publish updates? > > > > And yes, I can do this by de-serialaising data part, which should not be > > the case by my opinion, as this can be handled well-defined in metadata > > part. > > > > Can it be, > > "Items 'ver' can set by publisher..." > > s/can/MAY/ > > You're trying to maintain information coherence across different pubsub > services, which seems like a really hard thing to do. However, I can see > circumstances in which it's OK for the publisher to specify the version, > so we might want to relax the MUST to a SHOULD on the service-side, and > say that the publisher MAY specify the item version (but not the > versioning for the whole node). > > It's not so hard at all - and I'll proof it some point, needs some background documentation to be polished. And I really would priciate that change, as it'll not block the future changes like MUST would do. > over and out, thx. > > Heh, Jer used to use the short-form "oAo" when parting from chatrooms. > Maybe I'll bring that back. :) > > Peter > > -- > Peter Saint-Andre > https://stpeter.im/ > > > oAo - Ville
