Extending Sakai CLE to WebSphere and DB2

1. Extending Sakai CLE to WebSphere and DB2 Mr. Marty Banting, Sr. Software Engineer, IBM Mr. Howard Baker, Executive Project Manager, IBM Mr. John Bush, Development Manager, rSmart Mr. Earle Nietzel Software Engineer, Marist College Mr. Austin Schilling, IT Executive Consultant, IBM

2. Agenda • Amsterdam 2007 “recap” • Collaboration Team and Environment • Application Server and Database Considerations • Production at Marist College • Sakai Community Availability • Next Steps

3. Marist College, rSmart, IBM collaboration on Enterprise Sakai June 12, 2007

4. MARIST COLLEGE • We are NOT a large research university! • Founded 1929 – small complex liberal arts college • Approximately 5700 FTE student population • 200 full-time faculty, 500 part-time • Long history of incorporating technology into the teaching and learning process

5. Why do we need an extensible solution? Answer: We’ve learned our lesson from the past…

6. Learning from the past… • In 1996 the digital horizon was foggy… • We have a better view today… watch out! • Use and production of digital media will grow exponentially over next decade: • Electronic portfolios (oh yeah…“for life”) • Rich media learning objects (IVT Demo) • IdentityQuest Project (Podcasting Demo) • Next Up: Mobile authoring tools?

7. Marist College Evolving Learning Grid State and Local Consortia Museums, science centers, etc. Colleges and Universities K-12 District NSF MM Grid RPI, Lehigh,,Geneseo Greystone NYSTAR CCODC NSF IDCP FDR Sewall-Belmont Schema for Provisioning the Sharing of Resources/Tools Student content Certification Exams Online Courses “Raw” Video Content Sakai Repository

8. Marist/IBM Joint Study • Well Established Relationship, First Project – 1988 • Living Lab for New Technologies • Research projects, IBM Academic Initiative support, Marist grant initiatives • IBM program manager provides overall project management • IBM researchers, developers, business execs, and Marist faculty, IT staff, and students collaborate on numerous projects • Marist students hired as IBM interns • Opportunities for full-time positions

9. Marist Sakai Goals • How do we create a: • Standards based, • Capacity/Performance scalable, • Technology Extensible, • version of the Sakai CLE capable of handling future business and application needs • in a Services based infrastructure? • How can this vision be realized with the Sakai CLE deployment within the existing Joint Study infrastructure of: • WebSphere Application Servers, and • DB2 9 pureXML Technology Database?

10. Marist – rSmart – IBM Support • QA environment running DB2 and WAS will be live in September with several “flavors” of Sakai. • Marist will also be contributing several QA resources for testing activities

11. Global Campus Students Administrators Educators Customized Portals App 1 App 2 App 3 App 1 App 2 App 3 Collaborative Learning Environment Sakai Vision (2005) Sakai Tools & Development Environment Core Services: content, user, security, site Distributed Environment Core Infrastructure

12. Extending CLE Infrastructure (2007) Global Campus Students Administrators Educators Customized Po rtals App 1 App 2 App 3 App 1 App 2 App 3 Collaborative Learning Environment Relational Databases File Systems Sakai CLE v2.4.1 rSmart Distribution Core Services: content, user, security, site -X-Platform O/S - Slackware, RedHat, SuSE - WebSphere Application Server - DB2v9 SQL/XML Database -X-Platform O/S -Fedora, other Linux, Windows -Tomcat Application Server -My SQL Database + Others

13. Collaboration Team • IBM • Marty Banting • Alexander Reynolds • Robert Gilnack • Michael Ardizonne • Daniel Herman • Daniel Miller • Howard Baker • Austin Schilling • rSmart • John Bush • Michael Sanders • Tony Potts • Marist College • Earle Nietzel • John Digilio • Josh Baron

14. Marist iLearnODC History • Previous porting efforts included Sakai 2.2.2 and 2.3.1. • rSmart Sakai CLE 2.4 was next to be ported. • July & August • Sakai 2.4 port Development phase • September & October • Merged in Sakai 2.4.1 • Testing phase • November • UAT phase • December • Migrate IBM course to into production • Work in Progress

15. A Collaborative Effort • rSmart focused efforts on DB2 • IBM / Marist Joint Studies focused on Websphere • Weekly Checkpoint Meetings • Daily status calls • Scheduled builds • rSmart Jira rSmart Sakai CLE WAS/DB2 port (iLearnODC) rSmart Sakai CLE Sakai

16. Development & Build Tools Eclipse Rational Application Developer Rational Software Architect Maven, Subversion Testing IBM Linux Blades Slackware, SuSE v9 Apache Tomcat MySQL WebSphere v6.1.09 DB2 v9.3 rSmart Jira SVN Marist College SVN Porting Environment

17. Tool List • Blogger • Samigo • Announcements • Calendar • Melete • Gradebook • OSP Tools • Message Center • Site Stats • Site Info • Assignments • Syllabus • Roster • Profile • User Membership • rWiki • … and more!

18. The Challenges • Team members relatively new to Sakai • No proper debugging environment • Collaborative effort with a distributed team • Issues • Tomcat vs. Websphere related: 33 • Sun vs. IBM JDK/JRE related: 8 • DB2 related: 35 • Time to analyze and fix: ½ hour to 1.5 weeks

19. Porting for Websphere • Goal is to create a single codebase for both Tomcat and Websphere • Strived to make modifications app server independent • If not, then we used • Logical ‘if’ in Java code to check app server flag in sakai.properties • Websphere specific versions of xml/property config files

20. Websphere Porting IssuesDifferences in JDK/JRE • XML • Referencing vendor specific implementationseg. “com.sun.org.apache.xerces.internal.parsers.SAXParser” • Null attributes handled differently on XML document to string conversions

21. Websphere Porting IssuesDifferences in JDK/JRE • JSP • Quotes handled differently in JSP compilation<jsp:include page="<%= (String)request.getAttribute("_body")%>" />

22. Websphere Porting IssuesWAS vs. Tomcat • Deployment Descriptors • Tomcat is much more lenient with invalid deployment descriptors • If a web.xml file does not match the servlet specification it overlooks the error and allows the web application to function normally • WebSphere is much more strict • Will not allow an application to be installed unless there are no errors in the web.xml file

23. Websphere Porting IssuesWAS vs. Tomcat • Redirection / Navigation Issues • in Tomcat: getContextPath() = /osp-portal/tool/197c330a-8baf-4c0b-0018-3741f1eb3e87 In Websphere:request.getContextPath() = /osp-portal • Affects context.redirect calls eg. context.redirect("sakai.filepicker.helper/tool")

24. DB2 Porting Issues • Work Involved: • Creating db2 versions of all sql/ddl scripts • Reworking issues from core services • Hibernate Complications • Deal with non-standard persistence mechanisms in some tools (jforum and blogger) • Design Goals • one code base must support DB2 plus mysql and oracle • isolate changes 23

25. Core Services • No vendor specific abstraction in Sakai for dealing with vendor specific issues. • End up with code like this: if ("oracle".equals(m_sqlService.getVendor())) {... } else if ("mysql".equals(m_sqlService.getVendor())) { ... } else if ("db2".equals(m_sqlService.getVendor())) { ...} 24

26. For 2.5 • Core Services delegate to injected SQL helpers (SAK-8706) public interface ClusterServiceSql { String getListExpiredServers(long timeout); ... } public class SakaiClusterServiceSqlOracle extends SakaiClusterServiceSqlDefault{ public String getListExpiredServers(long timeout) { return "select SERVER_ID from SAKAI_CLUSTER where SERVER_ID != ? and UPDATE_TIME < (CURRENT_TIMESTAMP - " + ((float) timeout / (float) (60 * 60 * 24)) + " )"; }}public class SakaiClusterServiceSqlMySql extends SakaiClusterServiceSqlDefault{ public String getListExpiredServers(long timeout) { return "select SERVER_ID from SAKAI_CLUSTER where SERVER_ID != ? and UPDATE_TIME < CURRENT_TIMESTAMP() - INTERVAL " + timeout + " SECOND"; } 25

27. Refactor Status • Completed for event, content, cluster, site, user, authz, and db • Microsoft SQL Server implementations contributed (SAK-7002) • DB2 still left to do, for 2.6 ? 26

28. Hibernate and DB2 • length of index names (18 characters for DB2) • binary type • type mismatches in a few Samigo queries 27

29. DB2 Dialect • Good place for dealing with how Hibernate maps its types to the vendor • Can enforce column length limitations • Doesn’t provide a solution to all our problems.... 28

30. Hibernate UserTypes • Interface which allows you to control how a data element maps from the object model to the database and back public Object nullSafeGet(ResultSet resultSet, String[] names, Object owner) throws HibernateException, SQLException { final Object object; final Integer bigInt = resultSet.getInt(names[0]); if (bigInt == null) { return null; } return bigInt.toString(); } public void nullSafeSet(PreparedStatement statement, Object value, int index) throws SQLException { final String strValue = (String) value; if (strValue == null) { statement.setNull(index, Types.BIGINT); } else { statement.setInt(index, Integer.valueOf(strValue)); } } 29

31. Transforming hbm’s • Modified AdditionalHibernateMappingsImpl to apply a vendor specific xsl transformation to the hbm’s • This re-writes the hbm’s at runtime, “injecting” our custom UserTypes. • This avoids hacking up the hbms, with only a one line code change to this file. 30

32. Building & Deploying Tomcat components/ webapps/ components components components components war war shared/lib/ war war jar jar jar jar

33. Building & Deploying Websphere components/ installedApps/ components components components components EAR war war shared/lib/ war war jar jar jar jar

34. Build Process • Design Goals • Build process for Websphere as easy as Tomcat • Leverage existing build process with Maven 1.0.2 • Differences from Tomcat build • Copies Websphere specific XML and property files pre-compilation • Packages the WAR files into an EAR file • Copies components and shared libs to appropriate directory

35. Building Process • New ‘was’ module • starting point for Websphere build • contains overlay directory with the Websphere specific XML and property files • Gets copied into source pre-compilation • New ‘ear’ project within ‘was’ module • utilizes Maven EAR plugin • project.xml specifies WAR dependencies • New property (was.sakai_shared.home) in build.properties specifies where to deploy components and shared library files

36. Deployment Process • Deployed via Websphere Admin Console • Web based application for Websphere management • Setup shared library pointing to components and shared lib directory • Deploy as EAR file

37. Marist iLearnODC Production Status • Final Testing near completion • January 2008 • System Z Networking course online • March 2008 • 2 new courses online • Prepare to migrate Marist Courses • September 2008 • Sakai 2.4.1 production at Marist

38. Best practices • Use persistence frameworks • Consider the web framework • Don’t hard code implementations • Validate against specification 37

39. Next Steps • Form Platform Support WG • Refactor DB2 work to use new SQL helpers in 2.5 • Refactor/revisit some Websphere fixes • Establish better development environment for Websphere • Contribute low hanging fruit ASAP • Increase adoption of Sakai

40. Q & A

41. Technical Contacts John Bush (john.bush@rsmart.com) Marty Banting (mbanting@ca.ibm.com) Earle Nietzel (earle.nietzel@marist.edu) Austin Schilling (schill@us.ibm.com) Howard Baker (hcbaker@us.ibm.com)