WSCAF Demo

1
WS-CAF Demo

• A Demonstration of WS-CTX

2
WS-CAF In A Nutshell

• Collection of 3 specifications
• WS-Context, WS-Coordination Framework and
  WS-Transaction Management
• Designed to be used independently or together
• An open framework providing infrastructure
  support for applications that contain multiple
  services used in combination (composite
  applications)
• Enables composite applications to share common
  information
• Provides a normal session for the web services
  environment

3
WS-CAF In The Web Services Protocol Stack
4
WS-Context In A Nutshell

• Allows composite applications to share common
  information.
• Defines Notion of An Activity
• Unit of work
• Session construct
• Shared scope of persistent data
• Basic context associated with activity
• Defines web services for maintaining contexts
• 1 Activity per context
• Operations for creating, completing and getting
  status of a context.
• Ability to pass contexts by reference or by
  value.

5
WS-Context In A Nutshell (contd)

• Practical uses include
• Distributed web sessions (less restricted form of
  standard web cookie)
• Single sign-on
• Transaction propagation
• Processing of purchase order or travel
  itineraries

6
The Context Structure

• An XML document containing a unique identifier
  and optional data specific to a related activity.
• Typically included in the SOAP header of messages
  to and from web services participating in an
  activity.
• Can be passed as a referenceable URI (by
  reference) or in its longer form (by value)

7
Overview

• Demo loosely based on WS-I Sample Apps
• Consists of implementations of WS-CTX services
  and modified version of WS-I Sample App Retailer
  Service.
• Demonstrates interoperability between context
  implementations
• Each implementation has a web based UI that will
  be used as a driver for the demos.

8
WS-CTX Services Implemented

• ContextService
• begin(beginMsg)
• complete(completeMsg) // context passed in SOAP
  header
• UserContextService
• begun(begunMsg) //context passed in SOAP header
• completed(completedMsg) //context passed in SOAP
  header

9
Demo Flow

• User selects a catalogue of items from any store
  implementation.
• User selects items from catalogue and adds them
  to his cart.
• Store implementation begins new activity if
  there is no current shopping cart held by the
  user (no context in header).
• User can choose to add more items from the same
  or a different catalogue. Store implementations
  will add these items to the existing cart.
• User decides to finalize sale, by selecting a
  store (not necessarily one he has added items
  from), and submitting his order.
• Store implementation completes activity by
  calling complete on the ContextService referenced
  by the Context (using the context-service
  element).

10
Flow Example
CTX SVC. 1
3 begin
Store 1
1 getCatalog
2 addItemToCart
User
5 complete
Store 2
CTX SVC. 2
4 submitOrder