[SAGA-RG] SAGA SD Final?? Version

[Fisher, SM (Steve)]

> -----Original Message-----
> From: Andre Merzky [mailto:andre at merzky.net] 
> Sent: 24 January 2008 17:49
> To: Fisher, SM (Steve)
> Cc: SAGA RG
> Subject: Re: [SAGA-RG] SAGA SD Final?? Version
> 
> Hi Steve, 
> 
> here are my belated comments:
>  
> > #2  Should the default VOs be chosen from the session object?
> > 
> > As we are not able to come up with an intuitive syntax that 
> allows the
> > user to be able to request specific VOs or to take one from the
> > security context we prefer to leave this as it is. 
> 
> I was somewhat unclear here I guess, as you would need no
> additional syntax, but only additional semantics:
> 
>   // pseudocode!
> 
>   saga::context c ('X509');
> 
> 
>   c.set_attribute ('UserVO', 'O=dutchgrid');
> 
>   // create a saga session which uses that context
>   saga::session s;
>   s.add_context (c);
> 
>   // create a service discoverer in that session
>   saga::service::discoverer sd (s);
> 
>   // when searching for services, and when no VO filter is
>   // specified, we imply an VO filter from the session
>   // contexts
>   sd.discover ("Type = 'Broker' AND name = 'CERN-PROD-rb'",
>                "",
>                "RunningJobs > 10");
> 
>   // this is thus actually the same as:
>   sd.discover ("Type = 'Broker' AND name = 'CERN-PROD-rb'",
>                "VO IN ('O=Dutchgrid')",
>                "RunningJobs > 10");
> 
> The syntax is the same as before, but semantically, the
> empty VO filter is interpreted differently.
> 
> Does that make sense?  It would free the user from the need
> to explicitely filter for VOs.  In fact, as the session is
> defined to pick up default credentials, the user would not
> need to know anything about VOs at all, and still receive
> only services which are actually usable for his credentials.
> That should nicely fit to the 'S' in SAGA ;-)
> 
> OTOH, one can revert to the old semantics with the VO filter
> 'VO=*' (I guess?  Or is is "VO LIKE '%'"?).

I can see the attraction of your proposal - the only problem is that it
elsewhere if you specify no filter then everything is accepted, here you
you are giving a special meaning to the empty string. This then means
that you have to specify VO with a wildcard as you have suggested - i.e.
"VO LIKE '%'" I would quite like to hear the opinions of others on this.
 
> > #4  To mention compliance to upcoming GLUE stds. (GLUE 2?).
> >     Whether GLUE upgrades affect the document? if so, 
> >     appropriate mentioning required. (comments: similar to 
> >     SAGA-core spec depending on JSDL)
> > 
> > A footnote has been added
> > 
> > The examples have also been updated to correspond precisely to our
> > implementation.
> > 
> > Note that we do now have a complete C++ implementation with gLite
> > adapaters. The main code will be checked in as soon as Paventhan has
> > write access to the repositoy and the adapter code will go into the
> > gLite repository.
> > 
> > We would like to see the document go to the OGF editor now unless
> > somebody sees a problem. The .dvi file is attached.
> 
> I have a couple of minor suggestions for the text, mostly
> clarifying sentences I had difficulties to parse.  Do you
> want me to send it by mail, or would it be ok to change in
> CVS directly?

Please go ahead - I will see what you do!

Steve