ownedAuthority element

[Paul Harrison]

Matthew J. Graham wrote:
> Hi,
> 
> On Apr 6, 2005, at 2:30 AM, KevinBenson wrote:
> 
>> 3.) If harvester is a "Full Registry" then at an unknown time (presumably
>> when it kicks off its harvests), it MUST harvest any registry type 
>> that it
>> has been put as a <managedAuthority> and being managed by its own 
>> registry.
>> *Final note smaller publishing registries should be recommended to 
>> negotiate
>> on having a Full Registry manage its authority id.
> 
> 
> I think we need to be careful about mandating that Full Registries MUST 
> harvest any registry type.
> Suppose that someone puts up a publishing registry for a particular 
> specialist resource type for which they have defined their own set of 
> extension schema. The schema are horrendously complicated (even by IVOA 
> standards) and will not translate easily into a relational structure. 
> Unfortunately their local Full Registry is based on a relational db and 
> so will not harvest them. Of course, in this case, the publishing 
> registry could find another Full Registry that could contain their 
> contents but the point is that Full Registries are not necessarily full.
> 
>     Cheers,
> 
>     Matthew
> 
> 
One solution to this kind of problem is to give Full Registries the 
ability to delegate queries for certain authorityIDs on to the 
"publishing" registry that can handle the query. I know that this 
complicates the simple model of full and publishing registries that 
exists at the moment, but I think it might be unavoidable given.

1. The irreconcilable "world views" that different registry implementers 
have of the registry schema either define the data storage format or the 
exchange format

2. The schema are viewed by both camps as being extensible for 
specialist applications, so the full (rdb) registries will never be able 
to be up to date with the latest cutting edge application that someone 
wants to publish with a fancy extension.

So for each AuthorityID record in a "full" registry there would have to 
be a flag indicating whether to return an answer based on what it knows 
(and consequently it would have to harvest from the registry that owns 
the AuthorityID), or whether it should just pass the query on.

I think that there are very few implemetations out there where the 
registry software is not capable of being both a harvestable and 
querable registry - the real distinction is the the horsepower/bandwidth 
of the machine that the registry is installed on.

Paul


-- 
Paul Harrison
ESO Garching
www.eso.org