WS-Resource Framework
The WS-Resource Framework (WSRF) is a set of six
Web service specifications that define what is termed the WS-Resource approach to modeling and managing state in a Web services context. To date, drafts of three of these specifications have been released, along with an architecture document that motivates and describes the WS-Resource approach to modeling stateful resources with Web services. To be released soon are the other specifications, an overview document describing the relationship among the different specifications, and a document that compares the WS-Resource Framework with the Open Grid Services Infrastructure.
"And while Web services successfully implement applications that manage state today, we need to define conventions for managing state so that applications discover, inspect, and interact with stateful resources in standard and interoperable ways. The WS-Resource Framework defines these conventions and does so within the context of established Web services standards."
http://www.globus.org/wsrf/Modelling stateful Resources wih WebServicesGT4 Programmer's GuideWriting WSDL for stateful WebService
Implied Resource Pattern
The "implied resource pattern" is fundamental for WSRF. Copied from WSRF-FAQ:
"The phrase ?implied resource pattern? describes the way WS-Addressing is used to associate a stateful resource with the execution of message exchanges implemented by a Web service.
A WS-Addressing EndpointReference that follows the implied resource pattern must include a ReferenceProperties child element that identifies the resource to be associated with the execution of all message exchanges performed using this EndpointReference.
A Web services message that follows the implied resource pattern must be sent to a Web service referred to by an EndpointReference that follows the implied resource pattern, and must include the ReferenceProperties information from that EndpointReference, as specified by WS-Addressing.
A Web service that follows the implied resource pattern must use the ReferenceProperties information from a message that follows the implied resource pattern in order to identify the resource to associate with the execution requested by that message."
Thus: There is nothing like an "instance of a WebService". (Actually, we do not live in an OO-World!)
see also:
Implementations
WSRF Specifications
- WS-ResourceProperties (WSRF-RP)
- WS-ResourceLifetime (WSRF-RL)
- WS-ServiceGroup (WSRF-SG)
- WS-BaseFaults (WSRF-BF)
WSN Specifications
http://www.ibm.com/developerworks/library/specification/ws-notification/
The WS-Base Notification specification defines the Web services interfaces for NotificationProducers and NotificationConsumers. It includes standard message exchanges to be implemented by service providers that wish to act in these roles, along with operational requirements expected of them.
The WS-Topics specification defines a mechanism to organize and categorize items of interest for subscription known as "topics". These are used in conjunction with the notification mechanisms defined in WS-BaseNotification. WS-Topics defines three topic expression dialects that can be used as supscription expressions in subscribe request messages and other parts of the WS-Notification system. It further specifies an XML mode for describing metadata associated with topics.
The WS-BrokeredNotification specification defines the Web services interface for NotificationBroker. A NotificationBroker is an intermediary which, among other rhings allows publication of messages from entities that are not themselces service providers. It includes standard message exchanges to be implemented by NotificationBroker service providers along with operational requirements expected of service providers and requestors that participate in brokered notifications.
Comments
- Mainly a WS based Publish/Subscribe Framework.
- VERY LIMITED polling abilities (only the most recent Message of a Topic is adressed in the specification).
see also
BPMN
b_bprimal