1. Information Model, JSDL and XQuery: A proposed solution
Michel Drescher, Fujitsu
OGSA-16
Tampa, FL, USA

2. OGF IPR Policies Apply
“I acknowledge that participation in this meeting is subject to the OGF Intellectual Property Policy.”
Intellectual Property Notices Note Well: All statements related to the activities of the OGF and addressed to the OGF are subject to all provisions of Appendix B of GFD-C.1, which grants to the OGF and its participants certain licenses and rights in such statements. Such statements include verbal statements in OGF meetings, as well as written and electronic communications made at any time or place, which are addressed to:
the OGF plenary session,
any OGF working group or portion thereof,
the OGF Board of Directors, the GFSG, or any member thereof on behalf of the OGF,
the ADCOM, or any member thereof on behalf of the ADCOM,
any OGF mailing list, including any group list, or any other list functioning under OGF auspices,
the OGF Editor or the document authoring and review process
Statements made outside of a OGF meeting, mailing list or other function, that are clearly not intended to be input to an OGF activity, group or function, are not subject to these provisions.
Excerpt from Appendix B of GFD-C.1: ”Where the OGF knows of rights, or claimed rights, the OGF secretariat shall attempt to obtain from the claimant of such rights, a written assurance that upon approval by the GFSG of the relevant OGF document(s), any party will be able to obtain the right to implement, use and distribute the technology or works when implementing, using or distributing technology based upon the specific specification(s) under openly specified, reasonable, non-discriminatory terms. The working group or research group proposing the use of the technology with respect to which the proprietary rights are claimed may assist the OGF secretariat in this effort. The results of this procedure shall not affect advancement of document, except that the GFSG may defer approval where a delay may facilitate the obtaining of such assurances. The results will, however, be recorded by the OGF Secretariat, and made available. The GFSG may also direct that a summary of the results be included in any GFD published containing the specification.”
OGF Intellectual Property Policies are adapted from the IETF Intellectual Property Policies that support the Internet Standards Process. 2

3. Overview Two documents Goals A job description A resource description
Does the job meet the resource’s requirements?
<Capabilities>
</Capabilities>
<Capabilities>
</Capabilities>
<Requirements>
</Requirements>
<Requirements>
</Requirements>
Does the resource meet the job’s requirements? 3

4. Contents Foundations: XML Schemas Foundations: XML Documents
XQuery and context
Solution
Results 4

5. XML Schemas Information Model BES2 JSDL2
Makes use of Information Model
JSDL2 5

6. Info Model XML Schema <Requirements>
<XQuery> xs:string </XQuery>
</Requirements>
<Capabilities>
<Host/>+
<VO/>+
</Capabilities> 6

7. Info Model XML Schema (cont’d)
<Host>
<CPU>
<Architecture>
<CPUSpeed>
</CPU>
<OS>
<OSType>
<PhysicalMemory>
</OS>
<Software>
<Library>+
<SoftwarePackage>+
</Software>?
</Host>
<VO>
<Name/>
<Authentication>
<X509/>?
<UserPass/>?
</Authentication>
<Authorisation>
<TAN/>+
<Kerberos5/>+
</Authorisation>
</VO> 7

8. JSDL2 / BES2 XML Schema JSDL2 BES2 <JSDLJob> <Resources>
<im:Capabilities/>
<im:Requirements/>
</JSDLJob>
<Resources>
<im:Capabilities/>
<im:Requirements/>
</Resources> 8

9. Contents Foundations: XML Schemas Foundations: XML Documents
XQuery and context
Solution
Results 9

10. Sample JSDL2 document <Job> </Job> <Capabilities>
<VO>
<Name> DEISA </Name>
<Authentication>
<X509/>
<UserPass/>
<Authorisation>
<TAN/>
</Authorisation>
</VO>
</Capabilities>
<VO>
<Name> OGSA </Name>
<Authentication>
<X509/>
</Authentication>
<Authorisation>
<TAN/>
</Authorisation>
</VO>
<Requirements>
<XQuery>
im:OS/im:PhysicalMemory < 101
</XQuery>
</Requirements> 10

11. Sample BES2 document <Job> </Job> <Capabilities>
<Host Name=“Host1”>
<CPU/> ( Intel, 10 )
<OS/> ( Linux, 100 )
<Software/>
</Host>
<Host Name=“Host2”>
<OS/> ( Windows, 80 )
</Capabilities>
<Host Name=“Host3”>
<CPU/> ( AMD, 15 )
<OS/> ( Linux, 500 )
<Software/>
</Host>
<Host Name=“Host4”>
<OS/> ( Windows, 80 )
<Requirements>
<XQuery>
im:Name = 'OGSA-Grid' or count(im:Authentication/im:X509) >= 1
</XQuery>
</Requirements> 11

12. Contents Foundations: XML Schemas Foundations: XML Documents
XQuery and context
Solution
Results 12

13. im:PhysicalMemory element
Dynamic queries
XQuery is all about context
doc(“job.xml”) //
im:OS /
im:PhysicalMemory
<
101
external function 
document-node()
decendant-or-self:: 
node()
im:OS element 
element()
child:: 
element()
im:PhysicalMemory element 
element()
boolean expression 
xs:boolean
typed Atomic value 
xs:integer
How to provide the correct context? 13

14. Contents Foundations: XML Schemas Foundations: XML Documents
XQuery and context
Solution
Results 14

15. Providing context <Job> </Job> <Test> </Test>
<Resource>
</Resource>
<Capabilities>
</Capabilities>
<Capabilities>
</Capabilities>
<Capabilities>
</Capabilities>
<Capabilities>
</Capabilities>
<Requirements>
</Requirements>
<Requirements>
</Requirements>
<Requirements>
</Requirements>
<Requirements>
</Requirements>
<Requirements>
</Requirements>
<Requirements>
</Requirements> VO
Host VO
Host VO
Host 15

16. Assessing the results Number of VOs Number of Hosts
= 0: Job is not suitable
≥ 0: pick one VO
Number of Hosts
= 0: Can’t execute the Job
≥ 0: pick one
Host 16

17. Contents Foundations: XML Schemas Foundations: XML Documents
XQuery and context
Solution
Results 17

18. How XQuery is used XQuery is a suitable tool for our needs
XQuery used in separate domains
Requirements matching
Document management
Different domain usage allows:
(restricted XQuery set)
(full XQuery set) 18

19. Info Model work Controls how XQuery will be used
XML Element reuse vs. XQuery path assembly
Result should be reused in
JSDL2
BES (2?) 19

20. Results (3) Non-standard XQuery function Define OGSA wrapper
saxon:evaluate-node( $node )
Evaluates query stored in XML element
Define OGSA wrapper
Decouples functionality from used Interpreter
Implementation left to the user 20

21. Results (4) JSDL 1.0 extension Define requirements extension
Replaces the jsdl:Resources element
Query should match container resource description
Container requirements may query other JSDL extensions
Transparent to existing JSDL 1.0! 21