1. Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Accelerator Integrated Data Access Stanford Linear Accelerator Center George McIntyre, Greg White, Robert Sass, Ron MacKenzie, Judy Rock, Jingchen Zhou July 20th 2002 Software Framework and APIs Status and Further Work

2. Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Contents AIDA Vision Review Outline of Development Areas The data object design problem New Architecture Directory Service Schema Query Syntax (client code examples) Server Side Support (server code examples) Programmers’ Description of the Software Framework

3. Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Copyright © Stanford Linear Accelerator Center 2002 All rights reserved AIDA Vision Review Maps flat namespace onto application appropriate namespace

4. Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Vision Review continued Named regular expression query Query may result in structured data, returned to client Distributed data providers On different machines Running different operating systems Written in different languages Accessing different kinds of db (eg flat, relational, application eg BPM, model, archive) “Latency Appropriate”

5. Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Outline Development Areas Established CORBA as basic middleware (ORBACUS) Developed basic architecture Directory service concepts. Started populating with meta-data. Learnt to manage languages and tools (java, c++, JNI, CORBA; each on Solaris, NT, VMS; netbeans etc) Platform independent development environment (java IDE, CVS, make). Release is outstanding Developed Client server management. Server Persistence. Exception definition. Exception handling out of process, to CMLOG. Application Server Servlet displaying data to web. Web access of Names Directory Event based asynchronous exchange (using event service) Data Exchange. So far based on CORBA Any Performance tested alternative data exchange object types.

6. Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Copyright © Stanford Linear Accelerator Center 2002 All rights reserved CORBA data object? How is data wrapped for exchange across client and servers in series, such that its efficient and has an easy client and server API? CORBA ValueType (so called Object-by-Value) a possible candidate. But has interface difficulty and breaks the CORBA “paradigm”. Verified CORBA data exchange based on CORBA “Any” type is fast enough. Client application Server supplying data

7. CORBA Any Performance Same Host (slcs1)Different Host (slcsun1-slcs1) ValueType Wrapping union Orbacus Optimization OFF ValueType Wrapping union Orbacus Optimization ON Corba Any

8. Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Copyright © Stanford Linear Accelerator Center 2002 All rights reserved Questions What should be data object look like? If its based on Any, where is its functionality for helping the client use it implemented? If ValueType, what does calling architecture look like? What is its API? How can we pass “parameters”, but keep the API oriented towards general purpose data access. How do we make it latency appropriate? Can client programs be sensibly insulated from CORBA?