[RUS-WG] listMandatoryElements return type

[Gilbert Netzer]

Hi everybody,

please see also tracker artifact artf5890

http://forge.gridforum.org/sf/go/artf5890

for reference, I cuted most of the text from Rosarios eMail to make this 
thread more easy to follow...

I think that Donal's suggestion of using a XPath predicate to specify local 
constraints (and returning it via the listMandatoryElements method) is 
good. Definitely very flexible and easy to check at the client side. I 
would go for it!
However one word of caution, even though it may be very easy to check that 
a UR meets a given constraint (predicate evaluates to true), it might be 
hard to infer a acceptable UsageRecord from the given predicate (e.g. it 
can be hard for the client side to understand what is missing or wrong). I 
don't think this will be a big issue though. If the UR does not meet the 
local constraints, a human will have to inspect the situation anyway.

Best Regards
Gilbert Netzer

Rosario Michael Piro wrote:
[ cut a lot of text ]
> - The idea of using XPath expressions for defining the mandatroy 
> elements that have to be present for a UR to be accepted upon insertion 
> is good since it is the most flexible one, also: if the client queries 
> the RUS server for the mandatory elements it should be straightfoward 
> for the client to test its UR documents against the servers requirements 
> before trying to insert them into the RUS.
> 
> Those are just a few ideas for starting a discussion.
> 
> Cheers,
> 
> Rosario.