Sakai is an open source learning management system that was formed in January 2008 from the merger of the Sakai and Oncourse projects. It discusses the history and development of Sakai and Oncourse. Key components of Sakai include its use of Spring for dependency injection, Tomcat as the application server, and services/components that provide core functionality through APIs. The document provides an overview of how Sakai is structured and implemented.

1. Sakai
,
- , 1-2 , 2008
Sakai 构
Xingtang Hu(Hu2@iupui.edu)
Lance Speelmon(lance@indiana.edu)
Michael Korcuska(mkorcuska@gmail.com)
/ SAKAI
1 21 , 2008

2. ,
,
2006 /
2006
2002
2001
Lance Speelmon,
Oncourse Sakai 构 ,
Michael Korcuska,
Sakai 运

3. • Sakai
• Sakai 构
– Tomcat (classloader)
– Spring (components
manager)
• Sakai 开
– (Tools and services)
– (WebApp structure)
• Sakai

4. Sakai
•
• , ,
•
•
• Java
•

5. Sakai

6. • AuthzGroupService
• SiteService
• ToolManager
• SessionManager
• ContentHostingService
•
CourseManagementService

7. Sakai
•
– UserDirectoryProvider – map your local user information
(eg in LDAP, IMS Enterprise, Kerberos) into Sakai
– GroupProvider
– CourseManagementProvider
– PortalHandler (new in Sakai 2.4) – register new top-level
handlers in the Sakai portal URL space
– EntityProducer – export primary entities handled by your service as
1st-class Sakai “Entities” (resolvable by URLs, addressible by Events, searchable)
• Sakai

8. Sakai
• Sakai J2EE (Servlet)
(container)
– Tomcat, WebSphere, WebLogic
• Sakai (tool) ,
Servlet
• Sakai (component) Sakai API ,
Spring Beans

9. ,
• Tools(web)
– (persistence)
– presentation (GUI)
• Services / Components(API/Impl)
– Must provide documented API
– presentation (not aware of HTML at all)
– , (not data models)
• Framework(Tomcat)
– tools and service
– common capabilities
– domain objects

10. Sakai
• 构
Presentation Services (SAF)
TOOLS
•
• 离 Abstract Tool Layout
•
SERVICES Tool Code (Java)
•
•
•
(APIs)
FRAMEWORK
• Application Services
•
•
Common Services
(SAF)
Kernel (SAF)

11. Sakai 构
Shared
Model Logic-api Public-api
(business logic) (service)
Components
Dao-api
(data access)
Logic-impl
(business logic)
Webapps
Dao-impl
Tool (data access)
(presentation)
URL: http://issues.sakaiproject.org/confluence/x/BGo

12. 构
构 3-tier architecture External
Presentation User
Business Logic Other Apps
Data Access Database

13. Presentation Layer
3-tier architecture •
• (GUI)
Presentation
(client view)
•
Business Logic business logic
data
access
Data Access

14. Logic Layer
3-tier architecture •
Presentation •
•
(presentation)
Business Logic (data
access)
Data Access

15. Data Access Layer
3-tier architecture •
Presentation •
•
Business Logic (presentation )
(business logic)
Data Access

16. 关
3-tier architecture • ,
减
Presentation •
Business Logic
Data Access

17. Sakai
Component Manager
• Spring bean
Sakai ,
•
• Sakai

18. Sakai
Component Manager

19. Tomcat (Container)
Tomcat – The Server
Services
Engine (Catalina)
Hosts Realm
AJP Connector Valves
Context
8009
SSL Connector Valves JSPs Servlets
8443
HTTP Connector Valves
8080

20. Tomcat (J2EE)
• Java ClassLoaders
• Servlet (container)
• Web (ClassLoaders)
,

21. Sakai (ClassLoaders)
APIs up here
Components in here
Tools in here Component1 Component2
• Sakai J2EE ClassLoader layout
• Sakai (webapps) Servlets
– URLClassLoader
–
•
– components.xml (Spring file), web web.xml
– , Servlet (dispatches)

22. Sakai (Tools)
• Sakai (Tools) Servlet
– RSF, JSF Velocity
– web (web.xml) file (tools/
toolname.xml)
• App Builder (Plugin)
– (applicationContext.xml)
Spring (context) , Sakai
(services) Spring
– Spring (JARs ) 份,
(Web application)

23. Spring (beans)
• Spring (
(Dependency Injection)/
IoC )
• Java
(getters ) (setters)
• Spring
( init() )

24. Springy
• web.xml
(ContextLoaderListener)
• (bean definitions)
• Sakai
(services)

25. Sakai 开
• Sakai (component)
– (API module)
• Java (interface definitions)
(constants)
• JAR (shared area)
– (Impl module)
• (API interfaces )
• Spring (components.xml )
Spring (context)
• WAR (components area)

26. Sakai (Services)
• Sakai (services) Spring
(context) Spring beans
• 每 Sakai (component) Spring
components.xml
• Sakai 启 ,
.

27. Spring Sakai (Services)
• Sakai (APIs) Java (interfaces)
• 每 Sakai (APIs)
• Sakai Spring (components.xml) Spring bean
• : Spring Sakai
(UserDirectoryService)
<bean id="org.sakaiproject.user.api.UserDirectoryService“
class="org.sakaiproject.user.impl.DbUserService"
init-method=“init”
destroy-method="destroy" singleton="true">
......
<property name="autoDdl“ value=“${auto.ddl}”/>
<property name="cacheMinutes“ value=“5”/>
</bean>

28. ComponentManager
mgr.get(“org.sakaiproject.site.api.SiteService”);
• Spring
(ApplicationContext)
• id Class

29. Sakai 构
• 4
– Api (interfaces)
• Logic - business logic and dao apis
• Model - POJOs (value/data objects)
• Public - Service API (if you have one)
• Hbm - Hibernate HBM files
– Impl (implementations)
• Dao - data access implementation
• Logic - business logic implementation
• Tests - programmatic tests (unit/integration)
– Pack (component definitions)
• Spring (Sakai components.xml)
– Tool (webapp)
• Java src/java - java classes used by your tool only
• 关 src/webapp - xml, jsp, html, other meta files
URL: http://issues.sakaiproject.org/confluence/x/BGo

30. 构
URL: http://issues.sakaiproject.org/confluence/x/BGo

31. Sakai 构
• org.sakaiproject - base package prefix
– You could also use your local prefix (e.g. uk.ac.cam.caret)
• org.sakaiproject.app-name
• Use something unique for app-name, long is good
– dao - data access
– hbm – hibernate mapping files
– Logic – business logic
– Model – value/data objects
– Service – public api
– Tool – webapp
• Add impl to represent implementations
URL: http://issues.sakaiproject.org/confluence/x/BGo

32. 构
URL: http://issues.sakaiproject.org/confluence/x/BGo

33. Sakai Java
:
• ( event service)
• ActiveMQ 构

35. 2
1
m_eventTrackingService = (EventTrackingService) 3
ComponentManager.get("org.sakaiproject.event.api.EventTracking
Service");

36. Sakai
Sakai

37. Sakai Java (Applications)
Sakai
关
Sakai 启
Sakai 启

38. http://java.sun.com/products/jsp/
JSF http://java.sun.com/javaee/javaserverfaces/
http://www2.caret.cam.ac.uk/rsfwiki/
http://java.sun.com/products/servlet/
http://jakarta.apache.org/velocity/
AJAX http://en.wikipedia.org/wiki/AJAX

39. Java Server Pages
• 开
• 启 ,
• Sakai 运
• ,
•

40. JSF
Java Server Faces
• Java APIs
(managing state), (handling
events), (defining
navigation)
• JSP 渲
– JSPs 渲
• (tag libraries)
• ,
URL: http://java.sun.com/javaee/javaserverfaces/

41. JSF
<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %>
<html>
<head><title>JSF sample</title></head>
<body>
<f:view>
<h1><h:outputText value=“Hello #{user.name}"/></h1>
<h:dataTable id=“items"
value="#{itemsBean.items}" var=“item">
<h:column>
<h:outputText value="#{item.value}" />
</h:column>
</h:dataTable>
</f:view>
</body>
</html>

42. Reasonable Server Faces
• Spring (web
programming framework)
• XHTML , UI
Code 离
• Lightweight
• AJAX Javascript
URL: http://jakarta.apache.org/velocity/

43. <html>
<head><title>RSF sample</title></head>
<body>
<h1>Hello <span rsf:id=“user-name”>User Name</span></h1>
Today is <span rsf:id=“current-date”>1/1/2006</span><br/>
<table>
<tr rsf:id=“items:”>
<td rsf:id=“item-value”>item value here</td>
</tr>
</table>
</body>
</html>

45. Oncourse CL ,迁
Su/Fall 04 Spring 05 Su/Fall 05 Spring 06 Su/Fall 06
We Are Here – December 2005
Oncourse 2
Fall ’05 by Web form request only
Pilot Period – Limited Release
CL 1.5 CL 2.0 CL 2.1 CL 2.x
Sakai 开 构
Indiana, Michigan, Stanford Oncourse CL
and MIT
05 Oncourse CL

46. Oncourse CL 构
(IUB):
(IUPUI):

47. Sakai
•
WEB SYS
INSTITUTION USERS SITES SERVE INTEGRATION
RS
Indiana* 121,468 53,979 16 PeopleSoft
UNISA 92,000 4 Novell, ActiveDirectory
Michigan 67,281 17,453 8 UMIAC, Kerebos
Yale 14,569 4 Banner, CAS
Fernando Pessoa 5,250 2,000
UCT 4,040 48 2 PeopleSoft, Novell Nsure
Etudes Alliance** 2,560 79
UC, Merced 1,230 305 1 Banner, uPortal
Totals 308,398 73,864 34
*Indiana University: 2006 , 108,190 Oncourse CL .
**Etudes Alliance : 200 , 450 (07 02 ). Sakai
(Oncourse)

48. Sakai
•
• COMMUNITY PROCESSES — Sakai contact Mark Norton, Sakai
Community Process WG Chair (markjnorton@earthlink.net).
• 开 DEVELOPMENT — 开 join Sakai-Dev DG; review existing projects,
requirements, feature requests or contribute new tools and/or services; contact Peter
Knoop, Project Coordinator (knoop@umich.edu), or Anthony Whyte, Sakai Technical
Liaison (arwhyte@umich.edu).
• INFRASTRUCTURE — QA servers, JIRA/Confluence
hosting, contact Peter Knoop.
• QA — join QA Work Group, contact Megan May, QA Coordinator
(mmmay@indiana.edu).
• REQUIREMENTS & USE CASE DEVELOPMENT — join the
Requirements WG; contact Mara Hancock, REQ WG chair
(mara@media.berkeley.edu).

49. ?
http://sakaiproject.org/

50. Sakai
,
- , 1-2 , 2008
!
(hu2@iupui.edu)
Sakai/Oncourse
http://www.sakaiproject.org/