1. EGEE is a project funded by the European Union under contract IST-2003-508833 Report from the PTF Fabrizio Pacini Datamat S.p.a. Milan, IT-CZ JRA1 meeting, 23-24 Sept 2004 www.eu-egee.org

2. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 2 Contents Introduction Design Document DJRA1.2 Interface management (WSDL) Some Issues

3. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 3 Intro Meeting held on 14 Sept at CERN Focus on DJRA1.2 and DJRA1.3 Participation of experiment representatives  David Adams (ATLAS)  Ulrik Egede (LHCb)  Lassi Tuura (CMS) Agenda and minutes available at:  http://agenda.cern.ch/fullAgenda.php?ida=a043775

4. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 4 DJRA1.2 (1/5) … some specific comments/requirements Each service must provide a getVersion operation  APIs with optional methods should provide a means of querying which methods are supported Generalize the jobAssess interface: ETT is not enough  Examples: ETT, cost, capable resources, and available resources etc. Overuse of the "string“ type in many of the interfaces  Example: passing of the job JDL as a string  An XML representation including a schema for the JDL is strongly encouraged even if only for partial validation of job description

5. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 5 DJRA1.2 (2/5) … some specific comments/requirements The CE allows the jobid to be specified in the JDL  This open many possible avenues for malicious but not many benefits  the CE interface will always return an internally generated job identifier and that job identifier will be the one to query/manage the job on the CE. WMS/PM Interaction needs to be clarified  It must be possible to schedule jobs based on the available, installed software on a site  the package information needs to be embedded in the JDL  User jobs/Job Wrappers should be able to trigger the installation of "official“ experiment software

6. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 6 DJRA1.2 (3/5) … some specific comments/requirements Inspection of output for running jobs:  Typical use case: a user submits a large number of jobs but one is taking an extremely long time The user wants to be able to take a look at the "tail" of the output of that job The requirement coming from all experiments is:  User must be able to check (on demand) the standard output/error streams for running jobs WMS/DM Interaction needs to be clarified  It needs to be made clear whether the CE, RB, job wrapper script, or user is responsible for the download of data.  CMS would like to do scheduling based on datasets (which is not really file-based)  Metadata Interface

7. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 7 DJRA1.2 (4/5) … a general comment Some description on how the services interact with each other is missing in DJRA1.2 It has been agreed the need of a third document showing how the system behaves (sequence diagrams) for specific use cases Start with a few concrete test cases being developed by NA4 and use those as a basis for such a document This will not cover all services interactions, but this is a way of starting we’ll evaluate what needs to be done when the NA4 test cases are available

8. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 8 DJRA1.2 (5/5) … a general comment To help with the writing of the "third document"  the NA4 testing group has been charged to identify a few basic test cases and to ensure that those are satisfied on LCG-2  These will then be used as a basis for discussing the interactions of the various services in the gLite system. The NA4 database is proposed as the central location for requirements.  CL will follow up with the activity leaders to verify that this willingness is still there and to find volunteers to make sure the given requirement do show up in the database: http://egee-na4.ct.infn.it/requirements

9. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 9 Interface Management (1/2) The purpose of the discussion:  Decide how the actual services interfaces will be managed by the PTF. Conclusion:  WSDL will be used to describe the official APIs for the services (as it seemed the only solution for avoiding “ programming language wars “).  The PTF has the mandate to control changes to these interfaces hence they need to be versioned Current Status (layout of the modules within the JRA1 CVS repository):  Each module contains an associated "interface" module which is supposed to hold the public interface for the service.  Currently there is a mixture of WSDL and language-specific APIs in them.

10. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 10 Interface Management (2/2) Actions:  ADM and CL will work in the next two weeks to incorporate the WSDL mgt. and generation of various language bindings into the JRA1 build system. This will include the infrastructure to publish the documentation of the APIs.  JRA1 will work to have the WSDL for all of the services and to use them as the basis of the services by the end of October.  Each service will have to encompass a module containing only the WSDL interface to it

11. IT-CZ JRA1 meeting, Milan, 23-24 Sept 2004 - 11 Some Issues: Bulk submission Warm swap of the LB machine Discovery Service: how to use R-GMA for it Experiment specific catalog Delegation: how it will be incorporated into the services