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)

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