[glue-wg] Endpoints and ComputingService, relationships between services. Some thoughs

[Florido Paganelli]

Hi all,

I am in the situation that I would like to have a simple Endpoint 
published within a ComputingService. However, besides UML inheritance 
might allow this, the hierarchic xsd schema does not allow that, it only 
allows ComputingEndpoints to be nested within ComputingServices.

I don't know it this is good or bad; for you to understand how I got 
here, I can give you this little problem to solve:

Suppose the same machine hosts two RELATED services, that is, one needs 
the other one for proper functionality. For example a delegation service 
is needed to submit a job to a job execution service.

Is there a way for an information consumer to infer/understand this 
relationship? Can a client understand that (1) the services are related 
and (2) that they are running in the same machine just by looking at the 
GLUE2 records?

One might think of associations, but it can easily be shown that they 
don't solve the problem. We don't really have service-to-service 
associations, just some kind of hierarchy between services.

What do you think?
-- 
Florido Paganelli
Lund University - Particle Physics
ARC Middleware
EMI Project