IRS-III: A Platform and Infrastructure for Creating WSMO-based Semantic Web Services

John Domingue, Liliana Cabral, Farshad Hakimpour,

Denilson Sell, and Enrico Motta

Presentation @ WSMO Workshop, September 2004

The Internet Reasoning Service is an infrastructure for publishing, locating, executing and composing semantic web services, organized according to the WSMO framework

Design Principles

• Compatible with WSMO

• Tight integration

• Open

• Inspectable

• Backward compatible

• OWL-S import

• Research platform for semantic web services

Features of IRS-III (1/2)

• Based on Soap messaging standard

• Provides Java API for client applications

• Provides built-in brokering and service discovery support

• Provides capability-centred service invocation

Features of IRS-3 (2/2)• Publishing support for variety of platforms

– Java, Lisp, Web Applications, Java Web Services

• Enables publication of ‘standard code’ – Provides clever wrappers automatically, which turn code into web services– One-click publishing of web services

• Integrated with standard Web Services world– Published code appears as

• Semantic web service to IRS• ‘Ordinary’ web service to web service world

• IRS-III components are WSMO services – Web service discovery– Web service selection– Mediating input values

IRS-3 Server

Domain Models

Web Service Specifications+ Registry of Implementors

Goal Specifications+ SOAP Binding

IRS Publisher

S O

A P

IRS Client

SOAP

IRS Publisher

IRS Publisher

IRS Publisher

Lisp

Java

Java WS

IRS-3 Framework

LispWeb Server

IRS-III Architecture

IRS-III Server

WS Publisher Registry

OCML

WSMO Library

OWL(-S) HandlerOWL(-S)

Browser

Invocation Client

Publishing Clients

SOAP Handler

SOAP

Publishing Platforms

Web Service

Java Code

Web Application

SOAPBrowserHandler

PublisherHandler

InvocationHandler

Java

API

WSMX

Publishing Platform Architecture

IRS-III Publishing PlatformHTTP Server

SOAP Handler

ServiceRegistrar

ServiceInvoker

WS Service Registry

IRS-III Server

Invocation Client

SOAP

SOAP

Publishing Clients

SOAP

Web Service 1Web Service 2

Web Service 3

IRS-III/WSMO differences

• Underlying language OCML

• Goals have inputs and outputs

• IRS-III broker finds applicable web services via mediators– Used mediator within WS capability

– Mediator source = goal

• Web services have inputs and outputs ‘inherited’ from goal descriptions

• Web service selected via assumption (in capability)

Additional Mediators

• GW-Mediator– Transforms goal inputs -> web service inputs– WG-Mediator transforms web service output for goal

• GInv-GInv-Mediator– Mediates between two goal invocations

IRS-III Demo

SWS Creation & Usage Steps

• Create a goal description – (e.g. exchange-rate-goal)– Add input and output roles– Include role type and soap binding

• Create a wg-mediator description – Source = goal– Possibly add a mediation service

• Create a web service description– Used-mediator of WS capability = wg-mediator above

• Publish code or web service against web service description

• Invoke web service by ‘achieve goal’

Defining a Mediation Service

• Define a wg-mediator

• Source = goal

• Mediation-service = goal for mediation service

• Mediation goal – Mediation goal input roles are a subset of goal input

roles

• Define mediator and WS as normal

Exchange Rate Example (goal & mediator)

exchange-rate-goal (goal) has-input-role :value has_source_currency :value has_target_currency has-output-role :value has_exchange_rate has_source_currency :type currency has_target_currency :type currency has_exchange_rate :type positive-number

exchange-rate-mediator (gw-mediator) has-source-component :value exchange-rate-goal has-mediation-service :value exchange-rate-mediation-goal

Exchange Rate Example (WS & capability)

european-exchange-rate-web-service (web-service) has-capability :value european-exchange-rate-capability has-interface :value european-exchange-rate-web-service-interface

exchange-rate-capability (capability) used-mediator :value exchange-rate-mediator

european-exchange-rate-capability (exchange-rate-capability) has-assumption :value (kappa (?goal) (and (european-currency (wsmo-role-value ?goal 'has_source_currency)) (european-currency (wsmo-role-value ?goal 'has_target_currency))))

Exchange Rate Mediation Service Goal

exchange-rate-mediation-goal (goal) has-input-role :value has_source_currency has-output-role :value has_mediated_currency has_source_currency :type currency has_mediated_currency :type fully-named-currency

Goal Based Invocation

Invocation

Instantiate Goal Description

Exchange-rate-goal Has-source-currency: us-dollarsHas-target-currency: pound

Web Service Discovery

European-exchange-rate-wsNon-european-exchange-rate-wsEuropean-bank-exchange-rate-ws

Goal -> WG Mediator -> WS/Capability/Used-mediator

Web service selection

European-exchange-rate

Mediate input values

‘$’ -> us-dollar

WS -> Capability -> Assumptionexpression Mediation

Invoke selected web service

European-exchange-rate

Invocation

Summary

• IRS-III features– WSMO compatible platform

– Contains OWL-S import

– One click publishing

– Capability based invocation

• IRS-III mediators– WS ‘inherit’ input/output roles from goals

– Mediation service = goal

• Openness– WS discovery, WS selection, input value mediation,

orchestration are SWS

• Already used by attendees in 2 tutorials and will be shown at tutorial at ISWC