[jsdl-wg] Proposed Extension draft document

[Donal K. Fellows]

A S McGough wrote:
> He has a use case where he wants to perform a parameter sweep using a 
> program which takes a configuration file as the only input. The filename 
> is always the same (lets call it input.data) and the program has no way 
> to specify a different file name.
> 
> I can't see at the moment a way to deal with this without altering the 
> file staging elements which then places a dependency between file 
> staging and parameter sweep - not sure if this is a good idea. I suppose 
> it could be done by placing a wrapper around the program... again not 
> sure if this is good.

To me that sounds like what he needs is a way of applying some kind of
transformation to a template file that is then staged to the job
instance. Either that or a wrapper that takes as arguments the varying
parameters, sticks them into the config file, and then runs the wrapped
program. Conceptually they are about the same thing, I know, but the
difference is whether it is some kind of little workflow that does the
parameter application, or whether it is the job itself.

Another alternative would be to add a staging extension that allows the
staging source to be within the JSDL document itself in some way. IIRC,
BPEL has done something similar for "constant" arguments. With that,
applying changes through Michel's mechanism would be much easier.

Donal.