web modeling-based approach to automating web services mediation, choreography and discovery

Politecnico di MilanoDipartimento di Elettronica e Informazione

&

Web Modeling-based Approach to Automating Web Services Mediation,

Choreography and Discovery

SWS ChallengeStanford University, March, 8 2006

Marco Brambilla, Stefano Ceri, Dario Cerizza, Emanuele Della Valle, Federico Facca, Piero Fraternali, Christina Tziviskou

SWS Challenge 2006 2

Summary

Mediator modeling roadmap– BPM modeling (choreography)– WebML Domain modeling (ontology)– WebML Navigation modeling as high-level conceptual

description of mediators– Modeling of service invocation– Automatic generation of the mediator

Demo– Explanation– Demonstration

Managing of dynamics: how to Future vision


Mediator modeling roadmap

WebML framework

META-MODEL

Human Machine

Domain description meta-model

Entity Relationship

Navigation meta-model

Unit Link Page

Presentation meta-model

Page style Unit style Grid

Machine Machine

Domain description meta-model

Entity Relationship

Navigation meta-model

Request response Solicit Response

Presentation meta-model

Lowering Lifting

LANGUAGE XML Serialization

SOFTWARE SUPPORT

Design time

Run time

CASE tool & visual editor

Relational DB + views Java Beans

Runtime execution library

XML Serialization

Business process meta-model

WEB SITE

WEB SERVICES


WebML integratedBusiness process modelingtool

Support of

BPMN standardnotation

Automatic generation of the mediator WebML model based on business process patterns and standard description of activities


BPM modeling



WebML domain description modeling Ontological information described by extended E-R

meta-model

ShipmentService where ShipmentService.shipTo

not in ShipmentService.locatedIn

Self TO Europe where Self.locatedIn isa Europe


Feature of OWL-DL in webML domain description

WebML structural

+ (Ci ≠ ; A ≠ T)+ (A, Ci ≠ , T)-+--++ (Ci ≠ )+ (Ci ≠ )+ (must identify R and R- with the same name)---+ (domain(R2), range(R2) ≠ T)+ (domain(R2), range(R2) ≠ T)++--

+--rhsrhs--rhs rhsrhsrhsrhsrhs



WebML Hyper-text Navigation models

WebML has a conceptual language for the specification and design of distributed Web applications based on SOA paradigm– Content modeling

– Operations, execution flow and data flow modeling


Support of distributed hypertexts based on Service-Oriented Architectures and Web Services

Web service publishing


WebML Service Navigation models



From Business activity to Web Service

Each activity in the business process model of the mediator is translated in a pattern of WebML Service Navigation model. Such pattern consists of 4 standard steps:– Discovery invocation of GLUE discovery engine– Lowering data transformation from domain ontology to XML

representation for WS message – Invocation web service request response– Lifting data transformation from XML message to domain

ontology

Further refinement may be applied by the designer



Activity modeling in the hypertext Implementation for SWS Challenge Phase I:

– Discovery not needed– Some business actions follow the actual invocation:

• E.g., update of the state of the choreography

– Link topology may encapsulate programming logics

Lowering Lifting


Demo of the mediator

Two interfaces– one for machines

• A composed Web Service exposed to RosettaNet client for automatic enacting of the mediator process

– one for humans• An hyper-textual application for manual

inspection and execution of the process


Demo

RosettaNet System PO service

Receive PO

Obtain CustomerId

Create Order

Send Lines

Close Order


Demo

Moon Line Confirmation service

Receive Line Confirmations

Send POC

Demonstration


Managing dynamics.. How to

Changes in the domain modeling– Visual re-design of the ontology– Semi-automatic generation of the editing interfaces

for the instances of the ontology

Changes in the business process– Visual re-design of the business process

(choreography of the mediator)– Automatic generation of the mediator model (possibly

preserving unchanged activities)

Changes in the business partners– Discovery of partners Glue discovery engine


Managing dynamics

Addressing Challenge Phase II

domain modeling

business process

used service

Internal System Upgrade ++ ++ +

RosettaNet releases next version of PIP

++ ++ +

Discovery of new Business Partner

++

scen

ario

s ch

alle

nge

phas

e II

Type of dynamicschanges in …


Managing dynamics

GLUE as discovery engine GLUE

– is a WSMO compliant discovery engine • it aims at developing an efficient system for the manage-

ment of Semantic Web Services and their discovery.

– adopts a mediator centric approach• Provider and requester don’t have necessarily to agree on

using the same set ontologies in describing their goals and Web Services,

• But, they only have to agree in using compatible ontologies and in coding how to bypass heterogeneity using mediators:

– ggMediators are used for goal refinement– wgMediators are used for discovery

GLUEWSMO Discovery Engine

c2

a

ggMediator(goal refinement)

wgMediator(discovery)

c5c1 c2 c3 c4

a b bb c2

RE

QU

ES

TE

R

PR

OV

IDE

RS


Why Glue? SWS challenge scenario presents the kind of “polarization” in

the point of view of requesters and providers that justifies the use of Glue– different polarizations on different aspects

– Different understanding of exact matching• Products: […] a provider completely matches a request if all the requested

category of products are available and it partially matches in case a subset is available.

• Shipment Location: A service advertises the locations where it ships to. [If the requester wish to send goods in Bristol and the supplier ships to Europe, then an exact matching exists.]

• Shipment Price: [suppliers] might not always indicate a concrete price. • Payment Method: Both the requester and supplier advertise a list of acceptable

payment methods. […] We have a complete match if one payment method exist in common for requester and supplier

– Standard matching mechanism (i.e. DL-based ) are not sufficient.– Pairs of ggMediators and wgMediators can be used to model these

complex matching criteria

Aspect Requester SupplierProducts concrete list of products set of productsShipment Location concrete location set of locationsShipment Price preferences / restrictions (like less

than $100) concrete value, resp. functional dependency on selected products

Payment Method concrete list of accepted payment methods

concrete list of accepted payment methods


Conclusions and future works

The described methodology1. BPM models the choreography2. BPM case tool generates the WebML model of the mediator

• Both as a fully automatic mediator• And as an hyper-textual application for manual inspection and

execution of the process

3. WebML case tool enables the designer to refine the model • Defines ontologies, lowering and lifting, goal, web services

ggMediators, wgMediators, business logic, etc.

4. WebML case tools automatically generates the code Vision and future work

– Convergence of WebML – WSMO• Integration of GLUE• definition of WSMO goals at the BPM level (one goal for each

activity)


Thank you very much for your attention

Any question?Any question?

Emanuele Della ValleCEFRIEL

[email protected]

Marco BrambillaPolitecnico di Milano

[email protected]

Federico M. FaccaPolitecnico di Milano

[email protected]

web modeling-based approach to automating web services mediation, choreography and discovery

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