Am 05.12.2007 um 22:13 schrieb Peter Amstutz: > On Wed, Dec 05, 2007 at 11:43:47AM +0100, Karsten Otto wrote: >> Hi Peter, some questions/comments from the top of my head: >> >> What does importReplica() imply exactly? Is this just loading a local >> copy, or does it include contactig the remote site and merging >> updates? > > The idea is this is actually a copy of (a subset) of the site at some > revision. You're loading from this copy, which might have been > retrieved from the server, or maybe from somewhere else. After > loading > the replica, you might contact the server to find out if anything has > changed between the revision you have and the most recent > revision. It > is heavily inspired by distributed version control, although the focus > is more on disseminating signed updates from a central site than on > branching and merging. > Ok, I see. But this implies there could be more servers than just one, each hosting a replica. Which one do I contact for updates? With VOP/VIP URLs this was straightforward, but please remind me again, how do I contact a vos:0011223344... key-based site? Is there a name server somewhere?
>> The interface description seems to slowly approach WSDL Land... Have >> you considered some shorthand syntax to free a developer of all the >> XML clutter? Or do you envision GUI-based development tools for this >> (really the only way to live with WSDL if you have to use it)? > > I agree. It's not high on my own list of priorities, but this > would be > a good, easy project if someone wants to help out. (hint, hint) > I am tempted, but probably wouldn't get around to it for a while due to the workload of my current day job. Anybody else? :-) >> The fact that you need a *site* for an interface description seems >> pretty strange to me, even though I am aware you are re-using the XOD >> stuff for this... but do developers really have to generate a siteID >> key for every interface they design? Rather pointless, isn't it? >> While it may make sense to actually have the OTD vobject structure >> linked on a site that uses it, you usually don't know the target site >> (s) at development time. Maybe modify the XOD parser to consider the >> site/siteID optional, or use a shorthand syntax in the first >> place :-) > > That's because the site is actually part of the logical namespace. > What > this means is (site id shortened for brevity): > > vos:00112233/OTD/vos/FooClass > is entirely different from > vos:44556677/OTD/vos/FooClass > > Because the class vobject itself is a different vobject located on a > different site. This means an object that implements the first > "FooClass" is not necessarily compatible with the second "FooClass". > > Another way of thinking of it is that the act of defining and making > available the interface definition is the same as publishing any other > type of data via VOS. > Uh, okay... so... The "site" in this document is just a namespace, which makes sense given the new idea of a site being some abstract thing manifested only by lots of replicas. I.e. when I use the type vos:00112233/OTD/vos/FooClass I am using a replica of the abstract type definition. I was confused since I still though of a "site" as something you could connect to with Ter'angreal or mesh, while the new kind does not necessarily have any actual servers hosting the replicas. ... Right? > A large part of the change in terminology is due to an overall > change in > thinking. The idea is to not differentiate between local and remote > objects per se, but have "objects than I can change" and "objects I > need > to talk to someone else to change". Hence the notion of our local > copy > of such objects being a "replica", and if we know our local copy is up > to date (by checking revisions) then it is trivial to service read > requests using the local copy. > Ok, so the average user will never be concerned with MyTypeImpl, but only ever interacts with MyTypeWrapper? In this case I agree with reed to drop the Wrapper part and just call the thing MyType. Regards, Karsten Otto (kao) _______________________________________________ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d
