1. Web Services Context WS-CTX http://developers.sun.com/techtopics/webservices/wscaf/wsctx.pdf Presented by: Ioan Toma

2. Ioan Toma2 Overview Introduction Architecture –Components –Activities WS-CTX interactions Conclusions

3. Ioan Toma3 Introduction WS-CTX allows multiple Web services to share a common context structure

4. Ioan Toma4 Architecture WS-CTX represents a Web services interaction of a number of activities related to an overall application –Defines demarcation points between activates –Register Web services –Propagate context information WS-CTX components: –Context Service –Context –Activity Lifecycle Service

5. Ioan Toma5 WS-CTX components Context Service –defines the scope of an activity and how information about it (the context) can be referenced and propagated in a distributed environment. –is concerned with managing the lifecycle of context propagation. Activity Lifecycle Service –offer additional information to the basic context –registered with the Context service and are informed of the lifetime of an activity

6. Ioan Toma6 WS-CTX components (cont) Context contains information necessary for multiple Web services to be associated with the same activity. is modeled as a Web resource and is accessible via a URI consists of the following items: –A URI identifier - context identifier –Activity-service element – Context service identifier –Type of the activity identifier –List of the services currently participating in the activity – List of child activities –Timeout value transported in a SOAP header block

7. Ioan Toma7 WS-CTX Activity is a unit of (distributed) work, involving one or more parties (services, components, objects); a way of scoping application specific work has a status: active, completing, completed, no_activity, unknown has a completion status: success, fail, fail_only, unknown has a outcome that is returned to the initial Web service application

8. Ioan Toma8 WS-CTX Activity (Cont) Services involved within an activity: –Activity Lifecycle Service –Application Service

9. Ioan Toma9 WS-CTX interactions Enlisting and delisting an Activity Lifecycle Service by using two interfaces –ALSRegistrar (Context Service) enlistALS, delistALS –ALSRegistrant (ALS) enlisted, delisted, invalidALSFault, generalFalut

10. Ioan Toma10 WS-CTX interactions (cont) Interactions between ALS and Context Service –ALS (ALS endpoint) begin, completeWithStatus, complete, getIdentity –ALSRespondant (Context Service endpoint) begun, completedWithStatus, completed, identity, invalidALSFalut, validContextExpectedFault, generalFalut Interaction between Context Service and Users services –CTXService begin, complete, completeWithStatus, setCompletionStatus, getCompletionStatus, getStatus, getActivityName, getContext, setTimeout and getTimeout –UserCTXService begun, completed, completionStatusSet, completionStatus, status, activityName, context, timeoutSet, timeout, invalidStateFault, invalidActivityFault, timeoutOutOfRangeFault, childActivityPendingFault, noActivityFault, noPermissionFault, validContextExpectedFault

11. Ioan Toma11 Conclusions WS-CTX is intended as a lightweight mechanism for allowing multiple Web services to share a common context. WS-CTX defines the context, the scope of context sharing, and basic rules for context management.